Comparison of the sociodemographic characteristics of the large NutriNet-Santé e-cohort with French Census data: the issue of volunteer bias revisited

A population-based study of macronutrient intake according to mental health status with a focus on pure and comorbid anxiety and eating disorders

PURPOSE

Eating disorders (ED) and anxiety impact food choices. In addition, comorbid anxiety seems to increase ED symptoms and severity. However, the association between such comorbidity and dietary intake is unknown. This population-based, cross-sectional study aimed to assess macronutrient intake according to mental health status (i.e., no disorder, pure and comorbid anxiety and ED).

METHODS

The study included N = 24,771 participants (74% female, mean age = 53.2 ± 13.7 years) in the NutriNet-Santé cohort, who completed once the trait subscale of the State-Trait Anxiety Inventory (STAI-T; high anxiety: ≥ 40 points) between 2013 and 2016 and the SCOFF questionnaire screening for ED in 2014. The Expali algorithm was applied to categorize ED (no ED; restrictive: RS; bulimic: BL; hyperphagic: HP; other ED). Participants were divided into ten groups by crossing their anxiety status (two groups: low or high) and their ED status (five groups). Macronutrient intakes were evaluated from ≥ 3 24-h dietary records. Analyses of covariance (ANCOVA) and Dunnett-Hsu tests (reference = no disorder) were performed.

RESULTS

Significant differences in macronutrient intake were seen between the pure and comorbid forms, especially for RS and HP. Compared to the "no disorder" group, a significantly higher percentage of energy from carbohydrates, higher intakes of total carbohydrates, simple sugars, and plant-based protein, lower intakes of total fat, saturated and monounsaturated fatty acids, and cholesterol were observed in the comorbid anxiety + RS group, but not in the pure RS group. In contrast, significantly lower intakes of added sugar and plant-based protein, and a higher intake of cholesterol were observed in the pure HP group, but not in the comorbid anxiety + HP group. For BL and other ED, similar results were observed between the pure and comorbid forms.

CONCLUSION

This large epidemiological study provided some support for differences in macronutrient intake between individuals with pure or comorbid anxiety and ED. Differences in intake were largely dependent on ED type. Future prospective studies and studies using clinically defined anxiety and ED are needed to elucidate causality as well as potential effect modification of the observed associations.

Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols (FODMAPs) and cancer risk in the prospective NutriNet-Santé cohort

BACKGROUND

Fermentable Oligosaccharides, Disaccharides and Monosaccharides And Polyols (FODMAPs) have been shown to be involved in gastrointestinal disorders. In view of their pro-inflammatory potential and their interactions with the gut microbiota, their contribution to the etiology of other chronic diseases such as cancer has been postulated. However, no epidemiological study has investigated this hypothesis so far.

OBJECTIVE

Our objective was to investigate the associations between FODMAP intake (total and by type) and cancer risk (overall, breast, prostate and colorectal) in a large prospective cohort.

DESIGN

The study was based on the NutriNet-Santé cohort (2009-2020); 104,909 adult participants without cancer at baseline were included in our analyses (median follow-up time = 7.7y, 78.7% women, mean age at baseline 42.1y (SD = 14.5)). Baseline dietary intakes were obtained from repeated 24h-dietary records linked to a detailed food composition table. Associations between FODMAP intake (expressed in quintiles, Q) and cancer risks were assessed by Cox proportional hazard models adjusted for a large range of lifestyle, sociodemographic and anthropometric variables.

RESULTS

Total FODMAP intake was associated with increased overall cancer risk (n = 3374 incident cases, HR for sex-specific Quintile 5 versus Quintile 1: 1.21; 95%CI: 1.02, 1.44; P-trend = 0.04). In particular, oligosaccharides were associated with cancer risk: a trend was observed for overall cancer (HR Q5 vs. Q1: 1.10; 95%CI: 0.97, 1.25; P-trend = 0.04) and colorectal cancer (n = 272, HR Q5 vs. Q1: 1.78; 95%CI: 1.13-2.79; P-trend = 0.02).

CONCLUSION

Results from this large population-based study on French adults from the NutriNet-Santé cohort show a significant association between FODMAP intake and the risk of cancer development. Further epidemiological and experimental studies are needed to confirm these results and provide data on the potential underlying mechanisms.

Exposure to food additive mixtures in 106,000 French adults from the NutriNet-Santé cohort

Food additives (e.g. artificial sweeteners, emulsifiers, dyes, etc.) are ingested by billions of individuals daily. Some concerning results, mainly derived from animal and/or cell-based experimental studies, have recently emerged suggesting potential detrimental effects of several widely consumed additives. Profiles of additive exposure as well as the potential long-term impact of multiple exposure on human health are poorly documented. This work aimed to estimate the usual intake of food additives among participants of the French NutriNet-Santé cohort and to identify and describe profiles of exposure (single substances and mixtures). Overall, 106,489 adults from the French NutriNet-Santé cohort study (2009-ongoing) were included. Consumption of 90 main food additives was evaluated using repeated 24 h dietary records including information on brands of commercial products. Qualitative information (as presence/absence) of each additive in food products was determined using 3 large-scale composition databases (OQALI, Open Food Facts, GNPD), accounting for the date of consumption of the product. Quantitative ingested doses were estimated using a combination of laboratory assays on food matrixes (n = 2677) and data from EFSA and JECFA. Exposure was estimated in mg per kg of body weight per day. Profiles of exposure to food additive mixtures were extracted using Non-negative Matrix Factorization (NMF) followed by k-means clustering as well as Graphical Lasso. Sociodemographic and dietary comparison of clusters of participants was performed by Chi-square tests or linear regressions. Data were weighted according to the national census. Forty-eight additives were consumed by more than 10% of the participants, with modified starches and citric acid consumed by more than 90%. The top 50 also included several food additives for which potential adverse health effects have been suggested by recent experimental studies: lecithins (86.6% consumers), mono- and diglycerides of fatty acids (78.1%), carrageenan (77.5%), sodium nitrite (73.9%), di-, tri- and polyphosphates (70.1%), potassium sorbate (65.8%), potassium metabisulphite (44.8%), acesulfame K (34.0%), cochineal (33.9%), potassium nitrate (31.6%), sulfite ammonia caramel (28.8%), bixin (19.5%), monosodium glutamate (15.1%) and sucralose (13.5%). We identified and described five clusters of participants more specifically exposed to five distinct additive mixtures and one additional cluster gathering participants with overall low additive exposure. Food additives, including several for which health concerns are currently debated, were widely consumed in this population-based study. Furthermore, main mixtures of additives were identified. Their health impact and potential cocktail effects should be explored in future epidemiological and experimental studies.

Quality of Life in an e-Cohort of Women Treated by Endocrine Therapy for Early Breast Cancer

OBJECTIVE

The objective of our study was to analyze quality of life (QOL) in an e-cohort of patients treated for breast cancer (BC) by endocrine therapy (ET), by means of validated quality of life questionnaires.

STUDY DESIGN AND SETTING

A retrospective, observational, e-cohort study was conducted (Seintinelles platform). Female patients treated for nonmetastatic and nonrecurrent BC, treated in France after 2005, filled in online questionnaires concerning: QOL (QLQ-C30 and QLQ-BR23), tolerability of treatment and demographic characteristics. A multivariate analysis including variables significant on univariate analysis (P < .05) to select QOL predictors was performed.

RESULTS

We included 1,198 patients, 1140 of whom declared that they were taking ET (37.7% tamoxifen, 17.1% aromatase inhibitor (AI), 5.6% LHRH-agonist and 39.6% sequential tamoxifen and AI). Different tolerability profiles were observed when comparing the tamoxifen and AI groups. Treatment adherence was similar in the 2 groups. QOL varied slightly according to the type of ET. On multivariate analysis, ET had no impact on QOL. However, individual patient characteristics (socioeconomic, education and age) were significantly associated with QOL CONCLUSION: Using a real-life study questionnaire on a large e-cohort, individual patient characteristics were strongly associated with deterioration of QOL. The use of e-cohorts must be encouraged to modulate the conclusions of randomized trials.

Dietary macronutrient intake according to sex and trait anxiety level among non-diabetic adults: a cross-sectional study

Background

Studies suggest that anxiety is correlated with eating behavior, however, little is known about the association between anxiety status as predictor of dietary macronutrient intake. The aim of the present study was to investigate the sex-stratified cross-sectional associations of trait anxiety with intake of various macronutrients in a large population-based sample of non-diabetic adults.

Methods

N = 20,231 participants (mean age = 53.7 ± 13.6 years) of the NutriNet-Santé web-cohort, who had completed the trait anxiety subscale of the Spielberger State-Trait Anxiety Inventory (T-STAI; 2013–2016) were included in the analyses. Dietary intake was calculated from at least 3 self-administered 24-h dietary records. The associations of interest were assessed by multiple linear regression stratified by sex, owing to significant interaction tests.

Results

In total, 74.3% (n = 15,033) of the sample were females who had a significantly higher mean T-STAI score than did males (39.0 versus 34.8; p < 0.01). Among females, the fully-adjusted analyses showed significant positive associations of T-STAI with total carbohydrate intake (β = 0.04; p < 0.04), complex carbohydrate intake (β = 0.05; p < 0.02), and percentage energy from carbohydrates (β = 0.01; p < 0.03), as well as a significant inverse association of T-STAI with percentage energy from fat (β = -0.01; p < 0.05). As regards males, the only significant finding was an inverse association between T-STAI and percent of the mean daily energy from protein (fully-adjusted model: β = -0.01; p = 0.05).

Conclusion

This cross-sectional study found modest sex-specific associations between anxiety status and macronutrient intake among French non-diabetic adults. Prospective studies are needed to further elucidate the observed associations.

Glycaemic index, glycaemic load and cancer risk: results from the prospective NutriNet-Santé cohort

BACKGROUND

Evidence is accumulating that high dietary glycaemic index (GI) and glycaemic load (GL) are potential risk factors for several metabolic disorders (e.g. type-2 diabetes, cardiovascular diseases), but remains limited concerning cancer risk. Although, mechanistic data suggest that consuming high-GI foods may contribute to carcinogenesis through elevated blood glucose levels, insulin resistance or obesity-related mechanisms. Our objective was to study the associations between dietary GI/GL and cancer.

METHODS

In total, 103 020 French adults (median age = 40.2 years) from the NutriNet-Santé cohort (2009-2020) with no cancer or diabetes at baseline were included (705 137 person-years, median follow-up time = 7.7 years). Repeated 24-h dietary records linked with a detailed food-composition table (>3500 food/beverage items). We computed the average dietary GI and GL at the individual level. Associations between GI, GL, contribution of low- and medium/high-GI foods to energy and carbohydrate intake and cancer risk (overall, breast, prostate and colorectal) were assessed using multivariable Cox proportional-hazard models.

RESULTS

Higher dietary GL was associated with higher overall cancer risk [n = 3131 cases, hazard ratios (HRs) for sex-specific quintile 5 vs 1 = 1.25, 95% confidence interval (CI) = 1.03-1.52; Ptrend = 0.008] and specifically postmenopausal breast cancer (n = 924, HRQ5vs.Q1 = 1.64, 95% CI = 1.06-2.55; Ptrend = 0.03). A higher contribution of low-GI food/beverages to energy intake was associated with lower cancer risk whereas a higher contribution of medium/high-GI items to energy intake was positively associated with higher risk of overall, breast and postmenopausal breast cancers (Ptrend ≤ 0.02).

CONCLUSIONS

These results support a possible impact of GI/GL on cancer risk. If confirmed in other populations and settings, dietary GI/GL could be considered as modifiable risk factors for primary cancer prevention.

TRIAL REGISTRATION

https://clinicaltrials.gov/ct2/show/NCT03335644.

Social inequalities in participation in cancer screening: does the mode of data collection matter? The CONSTANCES cohort

BACKGROUND

Self-reported data are prone to item non-response and misreporting. We investigated to what extent the use of self-reported data for participation in breast (BCS) and cervical cancer screening (CCS) impacted socioeconomic inequalities in cancer screening participation.

METHODS

We used data from a large population-based survey including information on cancer screening from self-reported questionnaire and administrative records (n = 14 122 for BCS, n = 27 120 CCS). For educational level, occupation class and household income per capita, we assessed the accuracy of self-reporting using sensitivity, specificity and both positive and negative predictive value. In addition, we estimated to what extent the use of self-reported data modified the magnitude of socioeconomic differences in BCS and CCS participation with age-adjusted non-screening rate difference, odds ratios and relative indices of inequality.

RESULTS

Although women with a high socioeconomic position were more prone to report a date for BCS and CCS in questionnaires, they were also more prone to over-declare their participation in CCS if they had not undergone a screening test within the recommended time frame. The use of self-reported cancer screening data, when compared with administrative records, did not impact the magnitude of social differences in BCS participation but led to an overestimation of the social differences in CCS participation. This was due to misreporting rather than to item non-response.

CONCLUSIONS

Women's socioeconomic position is associated with missingness and the accuracy of self-reported BCS and CCS participation. Social inequalities in cancer screening participation based on self-reports are likely to be overestimated for CCS.

Self-reported periodontal health and incident hypertension: longitudinal evidence from the NutriNet-Santé e-cohort

OBJECTIVE

An association between periodontitis and arterial hypertension has been suggested recently. This study aimed at investigating the hypothesis that periodontal health is linked to incident arterial hypertension.

METHODS

We analyzed data from the French population-based e-cohort NutriNet-Santé, selecting participants who had completed two oral health questionnaires in 2011-2012. Pregnant women, participants with diabetes, cancer, arterial hypertension and cardiovascular diseases at inclusion were excluded. Incident cases of arterial hypertension were self-reported and/or based on the use of antihypertensive therapy. Periodontal health was evaluated by estimating the modified and validated PEriodontal Screening Score (mPESS), with mPESS at least 5 corresponding to a high probability of severe periodontitis. Descriptive statistics and Cox proportional hazards regression models, taking into account sociodemographic and lifestyle confounders, were used.

RESULTS

The study population consisted of 32 285 participants (mean age: 45.79 ± 13.87 years); 78.5% were women. Two thousand one hundred and sixteen incident cases of arterial hypertension were identified during a median follow-up of 8 years (April 2012--December 2019). In the fully adjusted model, an mPESS at least 5 [hazard ratio: 1.84; 95% confidence interval (CI): 1.66-2.03] and the presence of nonreplaced missing teeth (hazard ratio: 1.13; 95% CI: 1.03-1.23) were significantly associated with a greater risk of incident arterial hypertension, whereas a regular annual visit to the dentist was associated with a lower risk (hazard ratio: 0.88; 95% CI: 0.80-0.97).

CONCLUSION

Self-reported assessed periodontitis was associated with incident arterial hypertension over an 8-year period. The present results highlight the importance of considering periodontal health when assessing an individual's risk of arterial hypertension.

TRIAL REGISTRATION

# NCT03335644.

Prospective association between adherence to the 2017 French dietary guidelines and risk of death, CVD and cancer in the NutriNet-Santé cohort

Non-communicable diseases, such as cancers and CVD, represent a major public health concern, and diet is an important factor in their development. French dietary recommendations were updated in 2017, and an adherence score, the Programme National Nutrition Santé Guidelines Score (PNNS-GS2), has been developed and validated using a standardised procedure. The present study aimed to analyse the prospective association between PNNS-GS2 and the risk of death, cancer and CVD. Our sample consisted of French adults included in the prospective NutriNet-Santé cohort (n 67 748, 75 634 and 80 269 for the risk of death, cancer and CVD, respectively). PNNS-GS2 (range: -∞ to 14·25) was calculated from the 24-h dietary records of the first 2 years of monitoring. Association between PNNS-GS2 (in quintiles, Q) and the risk of death, cancer and CVD was studied using Cox models adjusted for the main confounding factors. The sample included 78 % of women, aged on average 44·4 years (sd 14·6) with on average 6·6 (sd 2·3) dietary records. Average PNNS-GS2 was 1·5 (sd 3·4) and median follow-up was 6·6 years for cancers and 6·2 years for CVD and deaths. PNNS-GS2 was significantly associated with the risk of death (hazard ratio (HR)Q5vsQ1: 0·77 (95 % CI 0·60, 1·00), 828 cases), cancer (HRQ5vsQ1 = 0·80 (95 % CI 0·69, 0·92), 2577 cases) and CVD (HRQ5vsQ1 0·64 (95 % CI 0·51, 0·81), 964 cases). More specifically, PNNS-GS2 was significantly associated with colorectal and breast cancer risks but not prostate cancer risk. Our results suggest that strong adherence to the 2017 French dietary recommendations is associated with a lower risk of death, cancer or CVD. This reinforces the validity of these new recommendations and will help to promote their dissemination.

Estimated dietary exposure to pesticide residues based on organic and conventional data in omnivores, pesco-vegetarians, vegetarians and vegans

PURPOSE

To examine dietary exposure to 25 pesticide residues in several diet groups including omnivores, pesco-vegetarians, vegetarians and vegans while accounting for the farming system (organic or conventional) of plant-based foods consumed.

METHODS

Organic and conventional consumption data in combination with data on pesticide residues in plant-based foods were used to derive estimated dietary exposure to pesticide residues. Pesticide residue exposure was estimated based on observed data, and using two scenarios simulated for 100%-conventional and 100%-organic diets in 33,018 omnivores, 555 pesco-vegetarians, 501 vegetarians and 368 vegans from the NutriNet-Santé study. Pesticide residue exposure across groups was compared using Kruskal-Wallis tests.

RESULTS

Exposure levels varied across diet groups depending on the pesticide studied. The highest exposure was observed for imazalil in all groups. Vegetarians appeared to be less exposed to the studied pesticides overall. Compared to omnivores - apart from pesticides authorised in organic farming - vegetarians had lowest exposure. The 100%-conventional scenario led to a sharp increase in exposure to pesticide residues, except for pesticides allowed in organic farming and conversely for the 100%-organic scenario.

CONCLUSIONS

Despite their high plant-based product consumption, vegetarians were less exposed to synthetic pesticides than omnivores, due to their greater propensity to consume organic.

Organic food consumption and gluten-free diet, is there a link? Results in French adults without coeliac disease

The rising popular belief that gluten is unhealthy has led to growth in gluten avoidance in people without coeliac disease. Little information is available on their dietary profiles and their dietary behaviours. Our aim was to compare the consumption of organic foods between gluten avoiders and non-avoiders, and their places of food purchase. We described their sociodemographic and dietary profiles. The study population included participants of the NutriNet-Santé cohort who completed both a food exclusion questionnaire and an organic semi-quantitative FFQ (n 23 468). Food intake and organic food consumption ratios were compared using multivariable adjusted ANCOVA models. Associations between gluten avoidance and organic food consumption as well as places of food purchase were investigated with multivariable logistic regression. Participants avoiding gluten were more likely to be women and had a healthier dietary profile. Organic food consumption was higher among gluten avoiders (48·50 % of total diet for total avoiders, 17·38 % for non-avoiders). After adjustments for confounders, organic food consumption and purchase in organic stores were positively associated with gluten avoidance: adjusted OR (aOR)Q5 v.Q1 organic food = 4·95; 95 % CI 3·70, 6·63 and aORorganic stores v.supermarkets = 1·82; 95 % CI 1·42, 2·33 for total avoiders. Our study highlights that individuals avoiding gluten are high organic consumers and frequently purchase their foods in organic stores which propose an extended offer of gluten-free food. Further research is needed to determine the underlying common motivations and the temporality of the dietary behaviours of healthy people avoiding gluten.

A Comparison of Sugar Intake between Individuals with High and Low Trait Anxiety: Results from the NutriNet-Santé Study

(1) Background: Dietary carbohydrates are likely correlated with mental health in general, and with anxiety in particular. Our aim was to investigate the cross-sectional relationship between trait anxiety and carbohydrate (especially sugar) intake in a large sample derived from the general French population. (2) Methods: The analyses included 20,231 non-diabetic adults enrolled in the NutriNet-Santé e-cohort, who had completed the trait anxiety subscale of the Spielberger State-Trait Anxiety Inventory (T-STAI, 2013–2016) and who were subsequently divided into high and low trait anxiety groups (T-STAI cut-off of 40 points). Sugar-rich food and macronutrient intake was calculated from ≥3 self-administered 24-h dietary records. The association between trait anxiety and carbohydrate intake was evaluated by ANCOVA according to age category (<45 and ≥45 years). (3) Results: In the full sample, 7942 (39.3%) individuals fell into the high trait anxiety category. They were more likely to be women (82.2% versus 69.2%; p < 0.0001) and younger (mean age 51.6 versus 55.1 years; p < 0.0001) compared to the low trait anxiety group. In fully-adjusted models, high-anxiety individuals aged under 45 years had significantly higher mean consumption of added simple sugars (43.9 versus 42.3 g/d; p < 0.0007), whereas those aged over 45 years with high trait anxiety had significantly lower mean consumption of fruit (214.0 versus 219.5 g/d; p < 0.02) compared to their low-anxiety counterparts. (4) Conclusions: This cross-sectional study revealed modest age-specific associations between anxiety status and sugar intake among adults. Prospective studies with representative samples are needed to explore potential bi-directionality of the observed associations.

Diet and physical activity during the coronavirus disease 2019 (COVID-19) lockdown (March-May 2020): results from the French NutriNet-Santé cohort study

BACKGROUND

Since December 2019, coronavirus disease 2019 (COVID-19) has been spreading steadily, resulting in overwhelmed health-care systems and numerous deaths worldwide. To counter these outcomes, many countries, including France, put in place strict lockdown measures, requiring the temporary closure of all but essential places and causing an unprecedented disruption of daily life.

OBJECTIVES

Our objective was to explore potential changes in dietary intake, physical activity, body weight, and food supply during the COVID-19 lockdown and how these differed according to individual characteristics.

METHODS

The analyses included 37,252 adults from the French web-based NutriNet-Santé cohort who completed lockdown-specific questionnaires in April-May 2020. Nutrition-related changes and their sociodemographic, lifestyle, and health-status correlates were investigated using multivariable logistic regression models. Clusters of participants were defined using an ascending hierarchical classification of change profiles derived from multiple correspondence analyses.

RESULTS

During the lockdown, trends of unfavorable changes were observed: decreased physical activity (reported by 53% of the participants), increased sedentary time (reported by 63%), increased snacking, decreased consumption of fresh food (especially fruit and fish), and increased consumption of sweets, cookies, and cakes. Yet, the opposite trends were also observed: increased home cooking (reported by 40%) and increased physical activity (reported by 19%). Additionally, 35% of the participants gained weight (mean weight gain in these individuals, 1.8 kg ± SD 1.3 kg) and 23% lost weight (2 kg ± SD 1.4 kg weight loss). All of these trends displayed associations with various individual characteristics.

CONCLUSIONS

These results suggest that nutrition-related changes occurred during the lockdown in both unfavorable and favorable directions. The observed unfavorable changes should be considered in the event of a future lockdown, and should also be monitored to prevent an increase in the nutrition-related burden of disease, should these diet/physical activity changes be maintained in the long run. Understanding the favorable changes may help extend them on a broader scale. This trial was registered at clinicaltrials.gov as NCT03335644.

Prospective association between dietary pesticide exposure profiles and postmenopausal breast-cancer risk in the NutriNet-Santé cohort

BACKGROUND

Some pesticides, used in large quantities in current agricultural practices all over Europe, are suspected of adverse effects on human reproductive health (breast and prostate cancers), through mechanisms of endocrine disruption and possible carcinogenic properties, as observed in agricultural settings. However, evidence on dietary pesticide exposure and breast cancer (BC) is lacking for the general population. We aimed to assess the associations between dietary exposure to pesticides and BC risk among postmenopausal women of the NutriNet-Santé cohort.

METHODS

In 2014, participants completed a self-administered semi-quantitative food-frequency questionnaire distinguishing conventional and organic foods. Exposures to 25 active substances used in EU plant-protection products were estimated using a pesticide-residue database accounting for farming practices, from Chemisches und Veterinäruntersuchungsamt Stuttgart, Germany. Non-negative matrix factorization (NMF), adapted for data with excess zeros, was used to establish exposure profiles. The four extracted NMF components' quintiles were introduced into Cox models estimating hazard ratio (HR) and 95% confidence interval (95% CI), adjusted for known confounding factors.

RESULTS

A total of 13 149 postmenopausal women were included in the analysis (169 BC cases, median follow-up = 4.83 years). Negative associations between Component 3, reflecting low exposure to synthetic pesticides, and postmenopausal BC risk were found [HRQ5 = 0.57; 95% CI (0.34; 0.93), p-trend = 0.006]. Positive association between Component 1 score (highly correlated to chlorpyrifos, imazalil, malathion, thiabendazole) and postmenopausal BC risk was found specifically among overweight and obese women [HRQ5 = 4.13; 95% CI (1.50; 11.44), p-trend = 0.006]. No associations were detected for the other components.

CONCLUSION

These associations suggest a potential role of dietary pesticide exposure on BC risk. Further research is needed to investigate the mechanisms and confirm these results in other populations.

Conservative to disruptive diets for optimizing nutrition, environmental impacts and cost in French adults from the NutriNet-Santé cohort

Improving the sustainability of diets requires the identification of diets that meet the nutritional requirements of populations, promote health, are within planetary boundaries, are affordable and are acceptable. Here we explore the extent to which dimensions of sustainability could be optimally aligned and identify more sustainable dietary solutions, from the most conservative to the most disruptive, among 12,166 participants of the NutriNet-Santé cohort. We aim to concomitantly lower environmental impacts (including greenhouse gas emissions, cumulative energy demand and land occupation), increase organic food consumption and study departure from observed diets (considered as a proxy for acceptability). From the most conservative to the most disruptive scenario, optimized diets were gradually richer in fruits, vegetables and soya-based products and markedly poorer in animal-based foods and fatty and sweet foods. The contribution of animal protein to total protein intake gradually decreased by 12% to 70% of the observed value. The greenhouse gas emissions from food production for the diets gradually decreased across scenarios (as a percentage of observed values) by 36-86%, land occupation for food production by 32-78% and energy demand by 28-72%. Our results offer a benchmark of scenarios of graded dietary changes against graded sustainability improvements.

Examining the municipal-level representativeness of the Canadian Longitudinal Study on Aging (CLSA) cohort: an analysis using Calgary participant baseline data

INTRODUCTION

The Canadian Longitudinal Study on Aging (CLSA) is a rich, nationally representative population-based resource that can be used for multiple purposes. Although municipalities may wish to use CLSA data to address local policy needs, how well localized CLSA cohorts reflect municipal populations is unknown. Because Calgary, Alberta, is home to one of 11 CLSA data collection sites, our objective was to explore how well the Calgary CLSA sample represented the general Calgary population on select sociodemographic variables.

METHODS

Baseline characteristics (i.e. sex, marital status, ethnicity, education, retirement status, income, immigration, internal migration) of CLSA participants who visited the Calgary data collection site between 2011 and 2015 were compared to analogous profiles derived from the 2011 National Household Survey (NHS) and 2016 Census datasets, which spanned the years when data were collected on the CLSA participants.

RESULTS

Calgary CLSA participants were representative of the Calgary population for age, sex and Indigenous identity. Discrepancies of over 5% with the NHS and/or 2016 Census were found for marital status, measures of ethnic diversity (i.e. immigrant status, place of birth, non-official language spoken at home), internal migration, income, retirement status and education.

CONCLUSION

Voluntary studies face challenges in recruiting fully representative cohorts. Communities opting to use CLSA data at a municipal level, including the 10 other CLSA data collection sites, should exercise caution when interpreting the results of these analyses, as CLSA participants may not be fully representative of the local population on select characteristics of interest.

Toward a Working Definition of eCohort Studies in Health Research: Narrative Literature Review

Background

The wide availability of internet-connected devices and new sensor technologies increasingly infuse longitudinal observational study designs and cohort studies. Simultaneously, the costly and time-consuming nature of traditional cohorts has given rise to alternative, technology-driven designs such as eCohorts, which remain inadequately described in the scientific literature.

Objective

The aim of this study was to outline and discuss what may constitute an eCohort, as well as to formulate a first working definition for health researchers based on a review of the relevant literature.

Methods

A two-staged review and synthesis process was performed comparing 10 traditional cohorts and 10 eCohorts across the six core steps in the life cycle of cohort designs.

Results

eCohorts are a novel type of technology-driven cohort study that are not physically linked to a clinical setting, follow more relaxed and not necessarily random sampling procedures, are primarily based on self-reported and digitally collected data, and systematically aim to leverage the internet and digitalization to achieve flexibility, interactivity, patient-centeredness, and scalability. This approach comes with some hurdles such as data quality, generalizability, and privacy concerns.

Conclusions

eCohorts have similarities to their traditional counterparts; however, they are sufficiently distinct to be treated as a separate type of cohort design. The novelty of eCohorts is associated with a range of strengths and weaknesses that require further exploration.

Association between adherence to the French dietary guidelines and the risk of type 2 diabetes

OBJECTIVE

French food-based dietary guidelines (FBDG) were updated in 2017. The objective of this prospective study was to estimate the associations between the Programme National Nutrition Santé-guidelines score 2 (PNNS-GS2), reflecting the level of adherence to the 2017 FBDG, and the risk of type 2 diabetes (T2D).

METHODS

A total of 79 205 French adult participants (mean age: 41.5 y [SD = 14.5]; 78.5% were women; 65% were postgraduate) from the NutriNet-Santé cohort (2009-2019) were included. Dietary intakes were collected using repeated 24-h dietary records. The PNNS-GS2 (theorical range: -∞ to 14.25), including six adequacy components and seven moderation components as well as a penalization on energy intake, was computed. The association between the PNNS-GS2 (as quintiles [Q]) and T2D risk was estimated using multivariable Cox proportional hazard models accounting for sociodemographic, anthropometric, and lifestyle and health-related factors.

RESULTS

During an average follow-up of 6.7 y (536 679 person-years), 676 T2D cases occurred. In the multiadjusted model, participants with the highest PNNS-GS2 (higher adherence to the 2017 FBDG), compared with those with the lowest (lower adherence to FBDG), exhibited a 49% reduction in risk of T2D (HR_{Q5 versus Q1}: 0.51, 95% CI: 0.37, 0.69). Body mass index accounted for up to 27% of the main association. The healthy profiles of the cohort's participants may have reduced statistical power.

CONCLUSIONS

In this large, prospective cohort study, a higher adherence to the French 2017 FBDG was strongly and inversely associated with the risk of developing T2D. Such analysis should be confirmed in other settings, but in terms of public health and nutritional policy, this study supports the relevance of the 2017 French FBDG.

Total and added sugar intakes, sugar types, and cancer risk: results from the prospective NutriNet-Santé cohort

BACKGROUND

Excessive sugar intake is now recognized as a key risk factor for obesity, type 2 diabetes, and cardiovascular diseases. In contrast, evidence on the sugar-cancer link is less consistent. Experimental data suggest that sugars could play a role in cancer etiology through obesity but also through inflammatory and oxidative mechanisms and insulin resistance, even in the absence of weight gain.

OBJECTIVE

The objective was to study the associations between total and added sugar intake and cancer risk (overall, breast, and prostate), taking into account sugar types and sources.

METHODS

In total, 101,279 participants aged >18 y (median age, 40.8 y) from the French NutriNet-Santé prospective cohort study (2009-2019) were included (median follow-up time, 5.9 y). Sugar intake was assessed using repeated and validated 24-h dietary records, designed to register participants' usual consumption for >3500 food and beverage items. Associations between sugar intake and cancer risk were assessed by Cox proportional hazard models adjusted for known risk factors (sociodemographic, anthropometric, lifestyle, medical history, and nutritional factors).

RESULTS

Total sugar intake was associated with higher overall cancer risk (n = 2503 cases; HR for quartile 4 compared with quartile 1: 1.17; 95% CI: 1.00, 1.37; Ptrend = 0.02). Breast cancer risks were increased (n = 783 cases; HRQ4vs.Q1 = 1.51; 95% CI: 1.14, 2.00; Ptrend = 0.0007). Results remained significant when weight gain during follow-up was adjusted for. In addition, significant associations with cancer risk were also observed for added sugars, free sugars, sucrose, sugars from milk-based desserts, dairy products, and sugary drinks (Ptrend ≤ 0.01).

CONCLUSIONS

These results suggest that sugars may represent a modifiable risk factor for cancer prevention (breast in particular), contributing to the current debate on the implementation of sugar taxation, marketing regulation, and other sugar-related policies. This trial was registered at clinicaltrials.gov as NCT03335644.

Prospective association between organic food consumption and the risk of type 2 diabetes: findings from the NutriNet-Santé cohort study

BACKGROUND

Organic food (OF) consumption has substantially increased in high income countries, mostly driven by environmental concerns and health beliefs. Lower exposure to synthetic pesticides has been systematically documented among consumers of organic products compared to non-consumers. While experimental studies suggest that pesticides currently used in food production may be associated with type 2 diabetes (T2D), no well-conducted prospective studies have investigated the potential association between consumption of organic products and the risk of T2D, controlling for potential confounding factors. The objective of this prospective study was to estimate the association between OF consumption and the risk of T2D.

METHODS

A total of 33,256 participants (76% women, mean (SD) age: 53 years (14)) of the French NutriNet-Santé prospective cohort study who completed the organic food frequency questionnaire were included (2014-2019). The proportion of OF in the diet (as weight without drinking water) was computed. The associations between the proportion of OF in the diet (as 5% increment and as quintiles) and the risk of T2D were estimated using multivariable Hazard Ratio (HR) and 95% confidence interval (95% CI) derived from proportional hazards models adjusted for confounders (sociodemographic, anthropometric, lifestyle, medical and nutritional factors).

RESULTS

During follow-up (mean = 4.05 y, SD = 1.03 y, 134,990 person-years), 293 incident cases of T2D were identified. After adjustment for confounders including lifestyle (physical activity, smoking status, alcohol consumption) and nutritional quality of the diet assessed by the adherence to the French food-based dietary guidelines, OF consumption was associated with a lower risk of T2D. Participants with the highest quintile of OF consumption, compared with those with the lowest quintile, had 35% lower risk of T2D (95% CI = 0.43-0.97). Each increment of 5% in the proportion of OF in the diet was associated with 3% lower risk of T2D (HR 0.97, 95% CI = 0.95-0.99).

CONCLUSIONS

In this large prospective cohort study, OF consumption was inversely associated with the risk of T2D. Further experimental and prospective studies should be conducted to confirm these observations.

CLINICAL TRIAL REGISTRY

The study was registered at ClinicalTrials.gov ( NCT03335644 ).

Alcoholic beverage consumption, smoking habits, and periodontitis: A cross-sectional investigation of the NutriNet-Santé study

BACKGROUND

Recent evidence suggests that dietary habits influence the development and severity of periodontitis. The present cross-sectional study evaluated the association between different types and quantity of alcoholic beverage consumption (alone and interacting with smoking) and the probability to suffer from severe periodontitis in the French e-cohort NutriNet-Santé.

METHODS

The study population consisted of 35,390 adults (mean age: 49.04 ± 13.94 years), who filled oral health questionnaires and completed at least three non-consecutive 24-hour dietary records. Data on type and frequency of alcoholic beverage consumption were obtained from a semi-quantitative self-reported alcohol frequency questionnaire; the daily quantity (g/day) was estimated from the 24-hour dietary records. The probability of severe periodontitis (main dependent variable) was assessed by calculating the modified periodontal screening score (mPESS) from selected questions.

RESULTS

A total of 7263 individuals (20.5%) presented a high probability of suffering from severe periodontitis (high-mPESS). After adjusting for confounding factors, the frequency of alcoholic beverage consumption was significantly higher among high-mPESS group than their low-mPESS counterparts, especially for hard liquor/spirits (1.9 ± 1.4 days/week for high-PESS versus 1.6 ± 1.1 days/week the low-PESS [P < 0.0001]). The mean daily quantity of ethanol was also higher in high-mPESS versus low-mPESS individuals (11.2 ± 15.6 versus 7.9 ± 12.3 g/day; P = 0.011). A stronger association with self-report severe periodontitis was noted when alcohol consumption exceeding > 20 g/day for women and > 30 g/day for men was combined with smoking habit (OR = 7.30 [95% CI: 6.1-8.73]).

CONCLUSION

The present results support an association between alcoholic beverage consumption and self-report severe periodontitis, particularly when it is associated with current smoking.

Knowledge and acceptance of interventions aimed at reducing sugar intake in Portugal

OBJECTIVE

Governments worldwide have been implementing interventions aimed at improving citizens' dietary habits. Examining how individuals perceive these interventions is relevant for promoting future policies in this area, as well as informing the way they are designed and implemented. In the current study, we focused on interventions aimed at reducing sugar intake in Portugal, given the current high sugar consumption patterns in the population.

DESIGN

Online survey to assess which interventions are the most salient and receive greater public support.

SETTING

Portugal.

PARTICIPANTS

1010 (76·7 % female, MAge 36·33, sd 13·22).

RESULTS

Data from a free-recall task showed that only about one-third of participants reported knowing about these interventions, namely those related to taxation, weight restrictions in individual sugar packets and limited availability of products with high sugar content. We also found evidence of high support for the eight interventions presented (except for replacing sugar by artificial sweeteners), positive attitudes towards the need of reducing sugar intake in the Portuguese population and high agreement with the importance of reducing sugar intake across all age groups, particularly among children. Participants also indicated paying attention to the amount of sugar in their diets and a low self-reported frequency of consumption of high sugary foods and beverages. A hierarchical regression analysis suggested that these variables were significantly associated with the overall acceptance of interventions, independently of social-demographic variables (i.e., age, education and sex).

CONCLUSION

By examining how people perceive and accept different interventions targeting the reduction of sugar intake, the current work aims to support policymaking in this domain.

Anxiety is a potential effect modifier of the association between red and processed meat consumption and cancer risk: findings from the NutriNet-Santé cohort

PURPOSE

Red and processed meats are recognized by the International Agency for Research on Cancer as probably carcinogenic and carcinogenic to humans, respectively. Heme iron has been proposed as a central factor responsible for this effect. Furthermore, anxiety affects the intestinal barrier function by increasing intestinal permeability. The objective of this work was to assess how anxiety modifies the association between red and processed meat consumption and cancer risk in the NutriNet-Santé prospective cohort (2009-2019).

METHODS

Using multi-adjusted Cox models in a sample of 101,269 subjects, we studied the associations between the consumption of red and processed meat, the amount of heme iron coming from these meats and overall, colorectal, prostate, and breast cancer risks, overall and separately among participants with and without anxiety.

RESULTS

An increase in red and processed meat consumption was associated with an increased risk of developing colorectal cancer in the total population (HR for an increase of 50 g/day = 1.18 (1.01-1.37), p = 0.03). After stratification on anxiety, the HR 50 g/day was 1.42 (1.03-1.94, p = 0.03) in anxious participants and 1.12 (0.94-1.33, p = 0.20) in other participants. Similar trends were observed for overall cancer risk. Analyses conducted with heme iron also provided similar results.

CONCLUSIONS

Our results strengthen the existing body of evidence supporting that red and processed meat consumption and heme iron intake are associated with an increased risk of overall and more specifically colorectal cancer, and suggest that anxiety modifies these associations, with an increased risk in anxious participants.

Ultra-processed food intake in association with BMI change and risk of overweight and obesity: A prospective analysis of the French NutriNet-Santé cohort

BACKGROUND

Ultra-processed food (UPF) consumption has increased drastically worldwide and already represents 50%-60% of total daily energy intake in several high-income countries. In the meantime, the prevalence of overweight and obesity has risen continuously during the last century. The objective of this study was to investigate the associations between UPF consumption and the risk of overweight and obesity, as well as change in body mass index (BMI), in a large French cohort.

METHODS AND FINDINGS

A total of 110,260 adult participants (≥18 years old, mean baseline age = 43.1 [SD 14.6] years; 78.2% women) from the French prospective population-based NutriNet-Santé cohort (2009-2019) were included. Dietary intakes were collected at baseline using repeated and validated 24-hour dietary records linked to a food composition database that included >3,500 different food items, each categorized according to their degree of processing by the NOVA classification. Associations between the proportion of UPF in the diet and BMI change during follow-up were assessed using linear mixed models. Associations with risk of overweight and obesity were assessed using Cox proportional hazard models. After adjusting for age, sex, educational level, marital status, physical activity, smoking status, alcohol intake, number of 24-hour dietary records, and energy intake, we observed a positive association between UPF intake and gain in BMI (β Time × UPF = 0.02 for an absolute increment of 10 in the percentage of UPF in the diet, P < 0.001). UPF intake was associated with a higher risk of overweight (n = 7,063 overweight participants; hazard ratio (HR) for an absolute increase of 10% of UPFs in the diet = 1.11, 95% CI: 1.08-1.14; P < 0.001) and obesity (n = 3,066 incident obese participants; HR10% = 1.09 (1.05-1.13); P < 0.001). These results remained statistically significant after adjustment for the nutritional quality of the diet and energy intake. Study limitations include possible selection bias, potential residual confounding due to the observational design, and a possible item misclassification according to the level of processing. Nonetheless, robustness was tested and verified using a large panel of sensitivity analyses.

CONCLUSIONS

In this large observational prospective study, higher consumption of UPF was associated with gain in BMI and higher risks of overweight and obesity. Public health authorities in several countries recently started to recommend privileging unprocessed/minimally processed foods and limiting UPF consumption.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03335644 (https://clinicaltrials.gov/ct2/show/NCT03335644).

Estimated dietary pesticide exposure from plant-based foods using NMF-derived profiles in a large sample of French adults

PURPOSE

This study, conducted in participants of the NutriNet-Santé cohort, aims to identify dietary pesticide exposure profiles (derived from Non-negative Matrix Factorization) from conventional and organic foods among a large sample of general population French adults.

METHODS

Organic and conventional dietary intakes were assessed using a self-administered semi-quantitative food frequency questionnaire. Exposure to 25 commonly used pesticides was evaluated using food contamination data from Chemisches und Veterinäruntersuchungsamt Stuttgart accounting for farming system (organic or conventional). Dietary pesticide exposure profiles were identified using Non-Negative Matrix factorization (NMF), especially adapted for non-negative data with excess zeros. The NMF scores were introduced in a hierarchical clustering process.

RESULTS

Overall, the identified clusters (N = 34,193) seemed to be exposed to the same compounds with gradual intensity. Cluster 1 displayed the lowest energy intake and estimated dietary pesticide exposure, high organic food (OF) consumption (23.3%) and a higher proportion of male participants than other groups. Clusters 2 and 5 presented intermediate energy intake, lower OF consumption and intermediate estimated pesticide exposure. Cluster 3 showed high conventional fruits and vegetable (FV) intake, high estimated pesticide exposure, and fewer smokers. Cluster 4 estimated pesticide exposure varied more across compounds than for other clusters, with highest estimated exposures for acetamiprid, azadirachtin, cypermethrin, pyrethrins, spinosad. OF proportion in the diet was the highest (31.5%).

CONCLUSION

Estimated dietary pesticide exposures appeared to vary across the clusters and to be related to OF proportion in the diet.

TRIAL REGISTRATION

Clinical Trial Registry: NCT03335644.

Characterization and Correction of Bias Due to Nonparticipation and the Degree of Loyalty in Large-Scale Finnish Loyalty Card Data on Grocery Purchases: Cohort Study

Background

To date, the evaluation of diet has mostly been based on questionnaires and diaries that have their limitations in terms of being time and resource intensive, and a tendency toward social desirability. Loyalty card data obtained in retailing provides timely and objective information on diet-related behaviors. In Finland, the market is highly concentrated, which provides a unique opportunity to investigate diet through grocery purchases.

Objective

The aims of this study were as follows: (1) to investigate and quantify the selection bias in large-scale (n=47,066) loyalty card (LoCard) data and correct the bias by developing weighting schemes and (2) to investigate how the degree of loyalty relates to food purchases.

Methods

Members of a loyalty card program from a large retailer in Finland were contacted via email and invited to take part in the study, which involved consenting to the release of their grocery purchase data for research purposes. Participants’ sociodemographic background was obtained through a web-based questionnaire and was compared to that of the general Finnish adult population obtained via Statistics Finland. To match the distributions of sociodemographic variables, poststratification weights were constructed by using the raking method. The degree of loyalty was self-estimated on a 5-point rating scale.

Results

On comparing our study sample with the general Finnish adult population, in our sample, there were more women (65.25%, 30,696/47,045 vs 51.12%, 2,273,139/4,446,869), individuals with higher education (56.91%, 20,684/36,348 vs 32.21%, 1,432,276/4,446,869), and employed individuals (60.53%, 22,086/36,487 vs 52.35%, 2,327,730/4,446,869). Additionally, in our sample, there was underrepresentation of individuals aged under 30 years (14.44%, 6,791/47,045 vs 18.04%, 802,295/4,446,869) and over 70 years (7.94%, 3,735/47,045 vs 18.20%, 809,317/4,446,869), as well as retired individuals (23.51%, 8,578/36,487 vs 31.82%, 1,414,785/4,446,869). Food purchases differed by the degree of loyalty, with higher shares of vegetable, red meat & processed meat, and fat spread purchases in the higher loyalty groups.

Conclusions

Individuals who consented to the use of their loyalty card data for research purposes tended to diverge from the general Finnish adult population. However, the high volume of data enabled the inclusion of sociodemographically diverse subgroups and successful correction of the differences found in the distributions of sociodemographic variables. In addition, it seems that food purchases differ according to the degree of loyalty, which should be taken into account when researching loyalty card data. Despite the limitations, loyalty card data provide a cost-effective approach to reach large groups of people, including hard-to-reach population subgroups.

Associations between consumption of dietary fibers and the risk of cardiovascular diseases, cancers, type 2 diabetes, and mortality in the prospective NutriNet-Santé cohort

BACKGROUND

Mounting evidence, yet with varying levels of proof, suggests that dietary fibers (DFs) may exert a protective role against various chronic diseases, but this might depend on the DF type and source.

OBJECTIVES

Our objectives were to assess the associations between the intake of DFs of different types [total (TDF), soluble (SF), insoluble (IF)] and from different sources (fruits, vegetables, whole grains, legumes, potatoes and tubers) and the risk of cardiovascular diseases (CVDs), cancer, type 2 diabetes (T2D), and mortality in the large-scale NutriNet-Santé prospective cohort (2009-2019).

METHODS

Overall, 107,377 participants were included. Usual DF intake was estimated from validated repeated 24-h dietary records over the first 2 y following inclusion in the cohort. Associations between sex-specific quintiles of DF intake and the risk of chronic diseases and mortality were assessed using multiadjusted Cox proportional hazards models.

RESULTS

T2D risk was inversely associated with TDFs [HR for quintile 5 compared with quintile 1: 0.59 (95% CI: 0.42, 0.82), P-trend <0.001], SFs [HR: 0.77 (0.56, 1.08); P-trend = 0.02], and IFs [HR: 0.69 (0.50, 0.96); P-trend = 0.004]. SFs were associated with a decreased risk of CVD [HR: 0.80 (0.66, 0.98); P-trend = 0.01] and colorectal cancer [HR: 0.41 (0.21, 0.79); P-trend = 0.01]. IFs were inversely associated with mortality from cancer or CVDs [HR: 0.65 (0.45, 0.94); P-trend = 0.02]. TDF intake was associated with a decreased risk of breast cancer [HR:: 0.79 (0.54, 1.13); P-trend = 0.04]. DF intake from fruit was associated with the risk of several chronic diseases.

CONCLUSIONS

Our results suggest that DF intake, especially SFs and DFs from fruits, was inversely associated with the risk of several chronic diseases and with mortality. Further studies are needed, involving different types and sources of fiber. Meanwhile, more emphasis should be put on DFs in public health nutrition policies, as DF intake remains below the recommended levels in many countries. This trial was registered at clinicaltrials.gov as NCT03335644.

Trends in response rates and respondent characteristics in five National Maternity Surveys in England during 1995-2018

Background

The National Perinatal Epidemiology Unit in England has conducted five National Maternity Surveys (NMS) at varying intervals since 1995. This paper aims to describe the changes in NMS response rates over time and to compare the demographic characteristics of respondents to each NMS.

Methods

This paper is based on secondary data analysis of the NMS (cross-sectional postal surveys) from 1995 to 2018. All women aged 16 years and over who gave birth in England (and Wales in 1995) during specified time periods from 1995 to 2018 were eligible to be selected. For each survey, between 3570 and 16,000 women who were 3–6 months postpartum were selected at random by the Office for National Statistics, using birth registrations. Women could participate on paper, by telephone (from 2006) or online (from 2010).

Results

The response rate to the NMS decreased from 67% in 1995 to 29% in 2018. The decline was evident across demographic groups. In all NMS, response rates were higher in women who were older (crude prevalence ratios (PR) for 16–24 years versus 30–34 years = 0.51–0.73 (across surveys)), married (crude PR for sole versus married registrants = 0.41–0.62), born in the UK (crude PR for non UK-born versus UK-born = 0.70–0.84), and living in less deprived areas (crude PR for least versus most deprived = 0.42–0.63). However, the association between each demographic characteristic and response varied across surveys, with the youngest women, women who registered the birth of the baby in their sole name, and women living in the most deprived areas becoming relatively less likely to respond over time. In multivariable analysis in 2014 and 2018, the effects of age, marital status, country of birth and level of area deprivation on response were attenuated but all four demographic characteristics remained statistically significantly associated with response.

Conclusions

Response rates to the NMS have declined significantly during the last 23 years. The demographic characteristics associated with response were consistent across surveys, but the size of the effect varied significantly, with underrepresented groups becoming relatively less likely to participate over time. It is important to find strategies to increase response rates, particularly amongst underrepresented groups, and to validate the data collected.

COllaborative open platform E-cohorts for research acceleration in trials and epidemiology

BACKGROUND

The current clinical research system relies on a "one-off" project-by-project model involving a costly and time-wasting permanent construction and deconstruction of the research infrastructure. We propose a new model of research relying on collaborative principles: the COllaborative Open Platform (COOP') e-cohort.

DEVELOPMENT

The COOP' e-cohort aims at building a large community of patients willing to participate in research by contributing to the generation of a large database of patient-reported data, passively enriched, at the individual level, by linkage with routinely collected care and/or medico-administrative data. Approved teams can use the platform and benefit from already enrolled participants or collected data or add new online questionnaires to perform observational or interventional studies to answer a broad range of research questions.

APPLICATION

The Community of Patients for Research (ComPaRe) is a proof-of-concept COOP' e-cohort in the field of chronic conditions that was launched in 2017. As of April 2020, 36,000 patients have joined the project and contributed to more than 4 million data points. Patient-reported data will be enriched by linkage with the French national health system databases and with hospital data for patients receiving care in the Paris region. Since 2017, 150 researchers have used the platform for research projects. Three clinical trials nested in ComPaRe have been funded.

CONCLUSION

By moving from myriad independent studies to a large collaborative infrastructure of research, COOP' e-cohorts will accelerate the research process by avoiding the redundancy of many steps common to all research projects and by limiting waste of research.

[Self-reported cancer in the German National Cohort (NAKO Gesundheitsstudie): assessment methods and first results]

BACKGROUND

In the German National Cohort (NAKO Gesundheitsstudie), the largest prospective cohort study in Germany, data on self-reported cancer diagnoses are now available for the first half of participants.

OBJECTIVES

Description of the methods to assess self-reported cancer diagnoses and type of cancer in the NAKO and presentation of first results.

MATERIALS AND METHODS

In a computer-assisted, standardized personal interview, 101,787 participants (54,526 women, 47,261 men) were asked whether they had ever been diagnosed with cancer (malignant tumors including in situ) by a physician and how many cancer diagnoses they had. The type of cancer was classified with a list. Absolute and relative frequencies of self-reported cancer diagnoses and types of cancer were calculated and compared with cancer registry data.

RESULTS

A physician-diagnosed cancer was reported by 9.4% of women and 7.0% of men. Of the participants who reported a cancer diagnosis, 88.3% reported to have had only one cancer diagnosis. In women, the most frequent malignancies were breast cancer, cervical cancer, and melanoma. In men, the most frequent malignancies were prostate cancer, melanoma, and colorectal cancer. Comparing the frequencies of cancer diagnoses reported by 45- to 74-year-old NAKO participants within the last five years to cancer registry-based 5‑year prevalences, most types of cancer were less frequent in the NAKO, with the exception of melanoma in men and women, cervical cancer and liver cancer in women, and bladder cancer and breast cancer in men.

CONCLUSIONS

The NAKO is a rich data basis for future investigations of incident cancer.

Ultraprocessed Food Consumption and Risk of Type 2 Diabetes Among Participants of the NutriNet-Santé Prospective Cohort

Importance

Ultraprocessed foods (UPF) are widespread in Western diets. Their consumption has been associated in recent prospective studies with increased risks of all-cause mortality and chronic diseases such as cancer, cardiovascular diseases, hypertension, and dyslipidemia; however, data regarding diabetes are lacking.

Objective

To assess the associations between consumption of UPF and risk of type 2 diabetes (T2D).

Design, Setting, and Participants

In this population-based prospective cohort study, 104 707 participants aged 18 years or older from the French NutriNet-Santé cohort (2009-2019) were included. Dietary intake data were collected using repeated 24-hour dietary records (5.7 per participant on average), designed to register participants' usual consumption for more than 3500 different food items. These were categorized according to their degree of processing by the NOVA classification system.

Main Outcomes and Measures

Associations between UPF consumption and risk of T2D were assessed using cause-specific multivariable Cox proportional hazard models adjusted for known risk factors (sociodemographic, anthropometric, lifestyle, medical history, and nutritional factors).

Results

A total of 104 707 participants (21 800 [20.8%] men and 82 907 [79.2%] women) were included. Mean (SD) baseline age of participants was 42.7 (14.5) years. Absolute T2D rates in the lowest and highest UPF consumers were 113 and 166 per 100 000 person-years, respectively. Consumption of UPF was associated with a higher risk of T2D (multi-adjusted hazard ratio [HR] for an absolute increment of 10 in the percentage of UPF in the diet, 1.15; 95% CI, 1.06-1.25; median follow-up, 6.0 years; 582 252 person-years; 821 incident cases). These results remained statistically significant after adjustment for several markers of the nutritional quality of the diet, for other metabolic comorbidities (HR, 1.13; 95% CI, 1.03-1.23), and for weight change (HR, 1.13; 95% CI, 1.01-1.27). The absolute amount of UPF consumption (grams per day) was consistently associated with T2D risk, even when adjusting for unprocessed or minimally processed food intake (HR for a 100 g/d increase, 1.05; 95% CI, 1.02-1.08).

Conclusions and Relevance

In this large observational prospective study, a higher proportion of UPF in the diet was associated with a higher risk of T2D. Even though these results need to be confirmed in other populations and settings, they provide evidence to support efforts by public health authorities to recommend limiting UPF consumption.

Trial Registration

ClinicalTrials.gov Identifier: NCT03335644.

Quality of life in the limelight: a study protocol of a Swedish register-based cohort study on quality of life after an injury

INTRODUCTION

Currently, there are very few published studies on preinjury and postinjury assessments of quality of life (QoL) based on a prospective appraisal; specifically, knowledge of those who do not seek medical care following injury is lacking. To close these knowledge gaps, this study aims to identify the psychosocial consequences in terms of loss of QoL following injury in a Swedish population and to investigate the response shift in retrospective measures of self-reported QoL.

METHODS AND ANALYSIS

We will analyse preinjury and postinjury (including both minor and severe unintentional injuries as well as different injury mechanisms) assessments of QoL, including the phenomenon of response shift, using register-based data from the nationwide collaboration project LifeGene, which includes over 52 000 individuals living in Sweden. In addition to LifeGene data, a short online survey including a 'ThenTest' questionnaire, that is, comparison of previous QoL to current using EuroQoL five-dimensional questionnaire, was sent out to the participants of LifeGene. This study will provide a unique opportunity to study the changes in QoL by comparing preinjury and postinjury assessments using a prospective appraisal, both for populations who have sought medical care as well as those who have not due to their injury. Similarly, the study will also assess the response shift in retrospective measures of QoL. This information can guide the next generation of QoL measures and interventions for those suffering injuries and have an impact on how to interpret evaluations of interventions.

ETHICS AND DISSEMINATION

The study has been reviewed and approved by the Regional Ethical Review Board in Stockholm, Sweden (case number 2018/352-31). The results will be disseminated through peer-reviewed journals, conference presentations, print media and internet and via a report for the funding agency.

Estimating sodium intake from spot urine samples at population level: a validation and application study in French adults

The aim of this study was to assess the validity of the predictive INTERSALT equation using spot urine samples to estimate 24-h urinary Na (24-hUNa) excretion and daily Na intake among the French adult population. Among 193 French adults ('validation sample'), we assessed the validity by comparing predicted 24-hUNa excretion from spot urine and measured 24-hUNa excretion from 24-h urine collections. Spearman correlation coefficients and Bland-Altman plots were used and we calculated calibration coefficients. In a nationally representative sample of 1720 French adults ('application sample'), the calibrated predictive equation was then applied to the spot urine Na values to estimate 24-hUNa excretion and daily Na intake. In that sample, predicted Na intake was compared with that estimated from 24-h dietary recalls. Results were adjusted and corrected using calibration coefficients. In the validation sample, the measured 24-hUNa excretion was on average 14 % higher than the predicted 24-hUNa (+13 % for men and +16 % for women). Correlation between measured and predicted 24-hUNa excretion was moderate (Spearman r 0·42), and the Bland-Altman plots showed underestimation at lower excretion level and overestimation at higher level. In the application study, estimated daily salt intake was 8·0 g/d using dietary recalls, 8·1 g/d using predicted INTERSALT equation and 9·3 g/d after applying calibration coefficients calculated in the validation study. Despite overall underestimation of 24-hUNa excretion by spot urinary Na, the use of predictive INTERSALT equation remains an acceptable alternative in monitoring global Na intake/excreted in the French population but its use is not advised at the individual level.

Combination of Healthy Lifestyle Factors on the Risk of Hypertension in a Large Cohort of French Adults

Background: Healthy lifestyle factors are widely recommended for hypertension prevention and control. Nevertheless, little is known about their combined impact on hypertension, in the general population. Our aim was to compute a Healthy Lifestyle Index (HLI) comprising the main non-pharmacological measures usually recommended to improve hypertension prevention: normal weight, regular physical activity, limited alcohol consumption, adoption of a healthy diet; to evaluate their combined impact on hypertension incidence. Methods: We prospectively followed the incidence of hypertension among 80,426 French adults participating in the NutriNet-Santé cohort study. Self-reported dietary, socio-demographic, lifestyle and health data were assessed at baseline and yearly using a dedicated website; the association between HLI and hypertension risk was assessed by multivariable Cox proportional hazards models adjusted for age, sex, family history of hypertension, socio-demographic and lifestyle factors. Hypothetical Population Attributable Risks associated to each factor were estimated. Results: During a median follow-up of 3.5 years (IQR: 1.5–5.3), 2413 incident cases of hypertension were identified. Compared with no or one healthy lifestyle factor, the hazard ratios (HR) for hypertension were 0.76 (95% CI, 0.67–0.85) for two factors, 0.47 (95% CI, 0.42–0.53) for three factors and 0.35 (95% CI, 0.30–0.41) for all healthy lifestyle factors (p-trend <0.0001). Compared with adhering to 0, 1, 2 or 3 healthy lifestyles, adhering to all of them was found associated with a reduction of the hypertension risk of half (HR = 0.55 (95% CI, 0.46–0.65)). Conclusion: Active promotion of healthy lifestyle factors at population level is a key leverage to fight the hypertension epidemic.

Sugary drink consumption and risk of cancer: results from NutriNet-Santé prospective cohort

OBJECTIVE

To assess the associations between the consumption of sugary drinks (such as sugar sweetened beverages and 100% fruit juices), artificially sweetened beverages, and the risk of cancer.

DESIGN

Population based prospective cohort study.

SETTING AND PARTICIPANTS

Overall, 101 257 participants aged 18 and over (mean age 42.2, SD 14.4; median follow-up time 5.1 years) from the French NutriNet-Santé cohort (2009-2017) were included. Consumptions of sugary drinks and artificially sweetened beverages were assessed by using repeated 24 hour dietary records, which were designed to register participants' usual consumption for 3300 different food and beverage items.

MAIN OUTCOME MEASURES

Prospective associations between beverage consumption and the risk of overall, breast, prostate, and colorectal cancer were assessed by multi-adjusted Fine and Gray hazard models, accounting for competing risks. Subdistribution hazard ratios were computed.

RESULTS

The consumption of sugary drinks was significantly associated with the risk of overall cancer (n=2193 cases, subdistribution hazard ratio for a 100mL/d increase 1.18, 95% confidence interval 1.10 to 1.27, P<0.0001) and breast cancer (693, 1.22, 1.07 to 1.39, P=0.004). The consumption of artificially sweetened beverages was not associated with the risk of cancer. In specific subanalyses, the consumption of 100% fruit juice was significantly associated with the risk of overall cancer (2193, 1.12, 1.03 to 1.23, P=0.007).

CONCLUSIONS

In this large prospective study, the consumption of sugary drinks was positively associated with the risk of overall cancer and breast cancer. 100% fruit juices were also positively associated with the risk of overall cancer. These results need replication in other large scale prospective studies. They suggest that sugary drinks, which are widely consumed in Western countries, might represent a modifiable risk factor for cancer prevention.

STUDY REGISTRATION

ClinicalTrials.gov NCT03335644.

Gluten-free diet in French adults without coeliac disease: sociodemographic characteristics, motives and dietary profile

The number of people avoiding gluten is growing in many Western countries. However, little information is available on their sociodemographic and dietary profiles. We aimed to describe sociodemographic, behavioural and dietary profiles of participants avoiding gluten in the NutriNet-Santé cohort. Participants of the NutriNet-Santé cohort – excluding coeliac patients – who completed a questionnaire about food exclusions, with complete data on sociodemographic characteristics and dietary intake were included (n 20 456). Food group consumptions and nutrient intakes according to self-reported avoidance of gluten were estimated using ANCOVA adjusted for age, sex and daily energy intake. Based on principal component analysis, three dietary patterns (DP) were identified. Association between DP and avoidance of gluten was investigated using multivariate logistic regression. All data were weighted on the French census. A total of 10·31 (95 % CI 9·90, 10·73) % of the participants declared avoiding gluten, of which 1·65 % totally. They were more likely to be women, older persons, non-smokers, to have a lower educational level and declared more food intolerances. They had higher consumption of fruit, vegetables and lower consumption of dairy products, salty/sweet and fatty foods and alcohol. After adjustments on confounders, a healthy dietary pattern was positively associated with total gluten avoidance (ORQuintile5vsQuintile1 = 14·44, 95 % CI 8·62, 24·19). Our study highlighted that, in this population, individuals who avoid gluten from their diet tend to have a diet more favourable to health. These results can serve as a basis for future studies investigating the potential consequences of a gluten-free diet in non-coeliac population.

Ultra-processed food intake and risk of cardiovascular disease: prospective cohort study (NutriNet-Santé)

OBJECTIVE

To assess the prospective associations between consumption of ultra-processed foods and risk of cardiovascular diseases.

DESIGN

Population based cohort study.

SETTING

NutriNet-Santé cohort, France 2009-18.

PARTICIPANTS

105 159 participants aged at least 18 years. Dietary intakes were collected using repeated 24 hour dietary records (5.7 for each participant on average), designed to register participants' usual consumption of 3300 food items. These foods were categorised using the NOVA classification according to degree of processing.

MAIN OUTCOME MEASURES

Associations between intake of ultra-processed food and overall risk of cardiovascular, coronary heart, and cerebrovascular diseases assessed by multivariable Cox proportional hazard models adjusted for known risk factors.

RESULTS

During a median follow-up of 5.2 years, intake of ultra-processed food was associated with a higher risk of overall cardiovascular disease (1409 cases; hazard ratio for an absolute increment of 10 in the percentage of ultra-processed foods in the diet 1.12 (95% confidence interval 1.05 to 1.20); P<0.001, 518 208 person years, incidence rates in high consumers of ultra-processed foods (fourth quarter) 277 per 100 000 person years, and in low consumers (first quarter) 242 per 100 000 person years), coronary heart disease risk (665 cases; hazard ratio 1.13 (1.02 to 1.24); P=0.02, 520 319 person years, incidence rates 124 and 109 per 100 000 person years, in the high and low consumers, respectively), and cerebrovascular disease risk (829 cases; hazard ratio 1.11 (1.01 to 1.21); P=0.02, 520 023 person years, incidence rates 163 and 144 per 100 000 person years, in high and low consumers, respectively). These results remained statistically significant after adjustment for several markers of the nutritional quality of the diet (saturated fatty acids, sodium and sugar intakes, dietary fibre, or a healthy dietary pattern derived by principal component analysis) and after a large range of sensitivity analyses.

CONCLUSIONS

In this large observational prospective study, higher consumption of ultra-processed foods was associated with higher risks of cardiovascular, coronary heart, and cerebrovascular diseases. These results need to be confirmed in other populations and settings, and causality remains to be established. Various factors in processing, such as nutritional composition of the final product, additives, contact materials, and neoformed contaminants might play a role in these associations, and further studies are needed to understand better the relative contributions. Meanwhile, public health authorities in several countries have recently started to promote unprocessed or minimally processed foods and to recommend limiting the consumption of ultra-processed foods.

STUDY REGISTRATION

ClinicalTrials.gov NCT03335644.

Patients' perspective on how to improve the care of people with chronic conditions in France: a citizen science study within the ComPaRe e-cohort

Background

This study aimed to involve patients with chronic conditions in generating ideas for improving their care.

Methods

We performed a citizen science study. Participants were adult patients with chronic conditions recruited in Community of Patients for Research ‘ComPaRe,’ a French e-cohort of patients with chronic conditions. Participants generated ideas to improve their care in answer to the open-ended question, ‘If you had a magic wand, what would you change in your healthcare?’ Three researchers and two patients independently extracted ideas from open-ended answers by using thematic analysis. Ideas were grouped into areas for improvement at the consultation, hospital/clinic and health system levels. Findings were validated and enriched by a second sample of participants recruited in ComPaRe.

Results

Between May 2017 and April 2018, a total of 1636 patients provided 3613 ideas to improve consultations (1701 ideas related to 58 areas for improvement), hospitals/clinics (928 ideas related to 41 areas for improvement) and the health system (984 ideas related to 48 areas for improvement). At the consultation level, most ideas were related to improving physician–patient discussions, informing patients about their own care, and adapting treatment to patient preferences and context. At the hospital/clinic level, most ideas aimed at improving the coordination and collaboration in care. At the health system level, most ideas were related to decreasing the administrative burden imposed on patients, improving access to care and reducing the costs of care.

Conclusion

Patients have many ideas to improve their care, from the content of consultations to the organisation of hospitals. Our study provides the proof of concept for a method to leverage patients’ practical knowledge of the care system to improve it.

Development and validation of an individual sustainable diet index in the NutriNet-Santé study cohort

In the current context of unsustainable food systems, we aimed to develop and validate an index, the sustainable diet index (SDI), assessing the sustainability of dietary patterns, including multidimensional individual indicators of sustainability. Based on the FAO's definition of sustainable diets, the SDI includes seven indicators categorised into four standardised sub-indexes, respectively, environmental, nutritional, economic and sociocultural. The index (range: 4-20) was obtained by summing the sub-indexes. We computed the SDI for 29 388 participants in the NutriNet-Santé cohort study, estimated its validity and identified potential socio-demographic or lifestyle differences across the SDI quintile. In our sample, the SDI (mean=12·10/20; 95 % CI 12·07, 12·13) was highly correlated to all the sub-indexes that exerted substantial influence on the participants' ranking. The environmental and economical sub-indexes were the most and less correlated with the SDI (Pearson R 2 0·66 and 0·52, respectively). Dietary patterns of participants with a high SDI (considered as more sustainable) were concordant with the already published sustainable diets. Participants with high SDI scores were more often women (24 %), post-secondary graduates (22 %) and vegetarians or vegans (7 %), without obesity (16 %). Finally, the SDI could be a useful tool to easily assess the sustainability-related changes in dietary patterns, estimate the association with long-term health outcomes and help guide future public health policies.

The association between physical and mental chronic conditions and napping

The objectives of this study were to assess the associations among various physical and mental chronic conditions and napping. A cross-sectional epidemiological survey was proposed within the NutriNet-Santé population-based e-cohort launched in France in 2009. Participants were 43,060 French volunteers aged 18 y and over with Internet access. A self-report questionnaire assessing sleep characteristics was administered in 2014. The main outcome (dependent) variable was weekday or weekend napping (yes/no). The main exposure (independent) variables were overweight/obesity, hypertension, diabetes, anxiety and depressive disorders, incident major cardiovascular diseases (myocardial infarction, stroke, unstable angina), and incident cancer (breast and prostate). The associations of interest were investigated with multivariable logistic regression analysis. No significant associations were found between major cardiovascular diseases or breast or prostate cancer and napping. Instead, we found that napping was more common among males (46.1%) than among females 36.9% (p < 0.0001). Individuals who were overweight or obese or had hypertension, diabetes, depression or anxiety disorders had an increased likelihood of napping compared with their healthy peers. The adjusted ORs ranged from 1.14 to 1.28″. In conclusion, most chronic conditions were independently associated with napping. Future longitudinal analyses are needed to elucidate causality.

Relationship between sensory liking for fat, sweet or salt and cardiometabolic diseases: mediating effects of diet and weight status

PURPOSE

Previous works have been suggested that individual sensory liking is a predictor of dietary intake and weight status, and may consequently influence development of cardiometabolic diseases (CMDs). We investigated the association between sensory liking for fat-and-salt, fat-and-sweet, sweet or salt and the onset of hypertension, diabetes and cardiovascular diseases (CVDs) over 6 years in adults, and the mediating effects of dietary intake and body mass index (BMI).

METHODS

We examined the CMDs risk among 41,332 (for CVD and diabetes) and 37,936 (for hypertension) French adults (NutriNet-Santé cohort). Liking scores, individual characteristics, diet and anthropometry were assessed at baseline using questionnaires. Health events were collected during 6 years. Associations between sensory liking and CMDs risk, and the mediating effect of diet and BMI, were assessed using Cox proportional hazards models.

RESULTS

Sensory liking for fat-and-salt was associated with an increased risk of diabetes, hypertension and CVD [hazard ratios (HR) for 1-point increment of the sensory score: HR 1.30 (95% CI 1.18, 1.43), HR 1.08 (1.04, 1.13) and HR 1.10 (1.02, 1.19), respectively]. BMI and dietary intake both explained 93%, 98% and 70%, of the overall variation of liking for fat-and-salt liking in diabetes, hypertension and CVD, respectively. Liking for fat-and-sweet and liking for salt were also associated with an increased risk of diabetes [HR 1.09 (1.01, 1.17) and HR 1.09 (1.01, 1.18), respectively], whereas liking for sweet was associated with a decreased risk [HR 0.76 (0.69, 0.84)].

CONCLUSIONS

Higher liking for fat-and-salt is significantly associated with CMDs risk, largely explained by dietary intake and BMI. Our findings may help to guide effective targeted measures in prevention.

Association of Frequency of Organic Food Consumption With Cancer Risk: Findings From the NutriNet-Santé Prospective Cohort Study

IMPORTANCE

Although organic foods are less likely to contain pesticide residues than conventional foods, few studies have examined the association of organic food consumption with cancer risk.

OBJECTIVE

To prospectively investigate the association between organic food consumption and the risk of cancer in a large cohort of French adults.

DESIGN, SETTING, AND PARTICIPANTS

In this population-based prospective cohort study among French adult volunteers, data were included from participants with available information on organic food consumption frequency and dietary intake. For 16 products, participants reported their consumption frequency of labeled organic foods (never, occasionally, or most of the time). An organic food score was then computed (range, 0-32 points). The follow-up dates were May 10, 2009, to November 30, 2016.

MAIN OUTCOMES AND MEASURES

This study estimated the risk of cancer in association with the organic food score (modeled as quartiles) using Cox proportional hazards regression models adjusted for potential cancer risk factors.

RESULTS

Among 68 946 participants (78.0% female; mean [SD] age at baseline, 44.2 [14.5] years), 1340 first incident cancer cases were identified during follow-up, with the most prevalent being 459 breast cancers, 180 prostate cancers, 135 skin cancers, 99 colorectal cancers, 47 non-Hodgkin lymphomas, and 15 other lymphomas. High organic food scores were inversely associated with the overall risk of cancer (hazard ratio for quartile 4 vs quartile 1, 0.75; 95% CI, 0.63-0.88; P for trend = .001; absolute risk reduction, 0.6%; hazard ratio for a 5-point increase, 0.92; 95% CI, 0.88-0.96).

CONCLUSIONS AND RELEVANCE

A higher frequency of organic food consumption was associated with a reduced risk of cancer. If these findings are confirmed, further research is necessary to determine the underlying factors involved in this association.

Influence of food preparation behaviors on 5-year weight change and obesity risk in a French prospective cohort

BACKGROUND

Food preparation behaviors may markedly determine dietary intake and consequently influence weight status. However, the few available studies have found equivocal results. No study has prospectively investigated the association between food preparation behaviors and weight change over time. We estimated the associations of food preparation behaviors with the 5-year relative weight change and the risk of developing obesity in 12,851 French adults participating in the NutriNet-Santé cohort study. The mediating effect of dietary intake was also addressed.

METHODS

Frequency and time for meal preparation, cooking skills, preparation from scratch, kitchen equipment, cooking enjoyment, willingness to cook better/more frequently and dietary intake were assessed at baseline using web-based questionnaire and 24 h records, respectively. Self-reported anthropometric data were collected using questionnaire, at baseline and after 5 years of follow-up. Associations of such behaviors with 5-year relative weight change and the mediation analyses were assessed through multivariate linear regression models, and obesity risk was analyzed with logistic regression, stratified by sex and adjusted for age, household composition, education, occupation, income, physical activity, smoking and history of dieting.

RESULTS

In women, preparation from scratch was prospectively associated with a decreased risk of obesity over the 5-year follow-up (OR = 1.32 (1.08; 2.32)) after adjustment. After including dietary mediating factors, the association between preparation from scratch and obesity risk in women did not remain significant (P = 0.08). This association appeared to be partly mediated by dietary factors with a difference of 59% of the estimate, in the group with the low score, between the adjusted model and those with mediators (OR = 1.13 (0.71; 1.77)). Regarding 5-year relative weight change, after adjustment for confounding factors, all associations between indicators of food preparation behaviors and weight change became non significant.

CONCLUSIONS

In the context from reduced time spent preparing meals that could have an impact on dietary quality and health in industrialized countries, our prospective study does not show effect of food preparation behaviors on 5-year relative weight change and obesity risk, except for preparation from scratch on obesity risk in women. Our study provides useful information about the long term implications of food preparation behaviors on health and should be corroborated by future studies, particularly on the effect of food preparation behaviors on chronic diseases such as incident diabetes, hypertension or cardiovascular diseases, compared with other determinants.

TRIAL REGISTRATION

NCT03335644 on ClinicalTrials.gov.

Sociodemographic correlates of eating disorder subtypes among men and women in France, with a focus on age

Background

On the population level, the association of age and other sociodemographic factors with eating disorders (ED) is unclear.

Methods

We used cross-sectional data from the French general population-based NutriNet-Santé e-cohort (n=49 603 adults; 76.3% women; mean age=50.4±14.6 years). ED were evaluated in 2014 with the 5-item SCOFF screening questionnaire and the Expali algorithmic tool. Likely cases of restrictive, bulimic, hyperphagic and other ED were the dependent variables. Age, marital status, education, occupation, physical activity and smoking were the independent variables. Associations were estimated via gender-stratified multivariable polytomous logistic regression.

Results

Among women, age displayed inverse linear associations with both restrictive and bulimic ED, underscoring 18–25 years as the most vulnerable period (adjusted OR=3.37, 95% CI: 2.24 to 5.08 for restrictive ED; adjusted OR=2.98, 95% CI: 2.37 to 3.74 for bulimic ED, respectively). A similar association was observed in men regarding bulimic ED. In women, age was not associated with hyperphagic ED for which living alone, low education, low physical activity, being a homemaker/disabled/unemployed/retired, a manual worker or a former/current smoker had increased importance. In men, 18–39 years emerged as the least vulnerable period regarding hyperphagic ED (adjusted OR=0.74, 95% CI: 0.56 to 0.99). Across gender, having postsecondary education had significant inverse associations with all except restrictive ED, whereas being a student had a significant positive association with restrictive ED.

Conclusions

The findings support gender-specific associations of age with four ED subtypes and could inform future prevention initiatives targeting specific ED among specific age groups.

Trial registration number

NCT03335644; Pre-results.

Macronutrient Intake in Relation to Migraine and Non-Migraine Headaches

We investigated the association of mean daily macronutrient intake with migraine and non-migraine headaches. This cross-sectional study included 8042 men and 23,728 women from the ongoing population-based NutriNet-Santé e-cohort. Headache status was assessed via an online self-report questionnaire (2013–2016). Migraine was defined using established criteria and dietary macronutrient intake was estimated via ≥3 24 h dietary records. Mean daily intake (g/day) of carbohydrates (simple, complex, and total), protein, and fat (saturated fatty acids, monounsaturated fatty acids, polyunsaturated fatty acids, and total) were the main exposure variables. Adjusted gender-specific analysis of variance (ANOVA) models were fit. Presence of migraines was noted in 9.2% of men (mean age = 54.3 ± 13.3 years) and 25.7% of women (mean age = 49.6 ± 12.8 years). In adjusted models, we observed (1) somewhat lower protein (p < 0.02) and higher total fat (p < 0.01) intake among male migraineurs compared with males without headaches and those with non-migraine headaches; (2) somewhat higher total fat (p < 0.0001) and total carbohydrate intake (p < 0.05) among female migraineurs compared with females without headaches and those with non-migraine headaches. The findings, which provide preliminary support for modest gender-specific differences in macronutrient intake by migraine status, merit confirmation in different population-based settings, as well as longitudinally, and could help to inform future dietary interventions in headache prevention.

Circadian nutritional behaviours and cancer risk: New insights from the NutriNet-santé prospective cohort study: Disclaimers

Circadian disruption has been classified as probably carcinogenic to humans by the World Health Organization's International Agency for Research on Cancer. The circadian clock is subject to environmental factors, particularly light exposure and food intake rhythms. However, the association between nutritional circadian behaviours and cancer is not well understood. We investigated the longitudinal associations between number of eating episodes, night-time fasting duration, time of first and last eating episodes, as well as nutritional quality of last eating episode, respectively, with breast and prostate cancer risks, the two main cancer locations in women and men respectively. This prospective study included 41,389 day-working adults in the French NutriNet-Santé cohort (2009-2016) who completed at least three 24 h dietary records during the first 2 years of follow-up. Multivariable Cox models were computed. 1,732 first primary incident cancer cases were diagnosed during the follow-up, among which 428 breast and 179 prostate cancers. After adjustment for covariates including sleep duration, late eaters (last eating episode after 9:30 pm) had an increased risk of breast (Hazard ratio [HR] = 1.48 [1.02-2.17], p = 0.03) and prostate (HR = 2.20 [1.28-3.78], p = 0.004) cancers. However, no association was observed between cancer risk and number of eating episodes, night-time fasting duration, time of first eating episode or macronutrient composition of the last eating episode. This large cohort study suggests that circadian perturbations resulting from late time of last food intake may be involved in carcinogenesis at different locations. Beyond nutritional quality of food intake, nutritional circadian regulation should be further investigated in the context of cancer prevention.