Adherence to a healthy Nordic food index and breast cancer risk: results from a Swedish cohort study

Association between overall diet quality and postmenopausal breast cancer risk in five Finnish cohort studies

There is limited evidence for any dietary factor, except alcohol, in breast cancer (BC) risk. Therefore, studies on a whole diet, using diet quality indices, can broaden our insight. We examined associations of the Nordic Diet (mNDI), Mediterranean diet (mMEDI) and Alternative Healthy Eating Index (mAHEI) with postmenopausal BC risk. Five Finnish cohorts were combined including 6374 postmenopausal women with dietary information. In all, 8–9 dietary components were aggregated in each index, higher total score indicating higher adherence to a healthy diet. Cox proportional hazards regression was used to estimate the combined hazard ratio (HR) and 95% confidence interval (CI) for BC risk. During an average 10-year follow-up period, 274 incident postmenopausal BC cases were diagnosed. In multivariable models, the HR for highest vs. lowest quintile of index was 0.67 (95 %CI 0.48–1.01) for mNDI, 0.88 (0.59–1.30) for mMEDI and 0.89 (0.60–1.32) for mAHEI. In this combined dataset, a borderline preventive finding of high adherence to mNDI on postmenopausal BC risk was found. Of the indices, mNDI was more based on the local food culture than the others. Although a healthy diet has beneficially been related to several chronic diseases, the link with the etiology of postmenopausal BC does not seem to be that obvious.

Fruit and vegetable consumption and incident breast cancer: a systematic review and meta-analysis of prospective studies

BACKGROUND

We conducted a systematic review and meta-analysis of prospective studies to clarify the relation of fruit and vegetable consumption with incident breast cancer.

METHODS

We searched systematically PubMed and EMBASE databases up to November 2020 to include prospective studies that reported the association of fruit and vegetable consumption with incident breast cancer. The pooled relative risks (RRs) and 95% confidence intervals (CIs) were calculated for the highest versus the lowest category of total fruit and vegetable, total fruit and total vegetable consumption, as well as fruit juice and subgroups of vegetables in relation to breast cancer incidence, using a random-effect model.

RESULTS

Total fruit and vegetable consumption was associated with lower overall (RR = 0.91, 95% CI = 0.87-0.95) and postmenopausal breast cancer risk (RR = 0.88, 95% CI = 0.79-0.99). Total fruit consumption was associated with lower overall (RR = 0.93, 95% CI = 0.88-0.99) and postmenopausal breast cancer risk (RR = 0.93, 95% CI = 0.87-0.99). Total fruit and vegetable intake were associated with 11% and 26% lower risk of oestrogen- and progesterone-receptor-positive (ER+/PR+) and -negative (ER-/PR-) breast cancer, respectively. Total vegetable consumption was associated with 27% lower risk of ER-/PR- breast cancer. Fruit juice consumption was associated with increased overall breast cancer risk (RR = 1.04, 95% CI = 1.01-1.07). We did not find significant associations for subgroups of vegetable intake and breast cancer risk.

CONCLUSIONS

These findings suggest that high total fruit and vegetable consumption are associated with reduced risk of overall, postmenopausal, ER+/PR+ and ER-/PR- breast cancer.

The Mediterranean and Nordic Diet: A Review of Differences and Similarities of Two Sustainable, Health-Promoting Dietary Patterns

The Mediterranean diet (MD) and the Nordic diet (ND) share more similarities than differences. Both diets are based on typical local and seasonal foods, share similar nutritional recommendations based on plant-based dietary principles, and are both now orienting toward environmental protection and sustainability. The main difference between the two diets is the primary fat source. Olive oil is the synonym for MD while the ND uses more rapeseed/canola oil. While longitudinal epidemiological studies support adherence to MD as a way to prevent chronic diseases, ND still needs more such studies because the current results are discrepant. Notably, studies that assessed the association between both diets and lower risks of chronic diseases, disability, and mortality from specific and all causes, implied that ND could also have an advantageous effect as MD. Hopefully, there will be more longitudinal and large prospective studies in the future that will provide more evidence-based recommendations.

The Recommended Food Score and Healthy Nordic Food Index in cardiovascular disease and stroke: A systematic review

BACKGROUND

Cardiovascular disease (CVD) includes a group of heart and coronary disorders that can be prevented by promoting the quality of an individual’s diet. The Recommended Food Score (RFS) and Healthy Nordic Food Index (HNFI) are suggested for the assessment of diet quality and as indicators of dietary exposures related to disease. The aim of this study was to systematically review the association of the RFS and the HNFI with CVD and stroke.

METHODS

Articles were identified by searching PubMed, Google Scholar, and ScienceDirect using relevant keywords for articles published until December 2018. The inclusion criteria were all types of observational studies and English language. Non-English and irrelevant studies were excluded.

RESULTS

In total, 14 studies met the inclusion criteria. Of the 7 studies that investigated the association between the RFS and CVD, 6 articles showed a lower risk of CVD in individuals who obtained a higher RFS and lower non-RFS (n-RFS) score. Studies that investigated the relation between RFS and stroke (n = 2) showed that achieving a higher RFS could decrease the risk of stroke. Of the 4 studies that assessed the relationship between HNFI and CVD, 3 showed that adherence to HNFI were related with lower risk of CVD/stroke. However, one study did not show any relationship.

CONCLUSION

A higher RFS may result in a decrease in the risk of CVD and stroke. Due to the inconsistency of the findings related to HNFI, more studies are needed to approve the negative relationship between HNFI and CVD.

The Nordic diet and the risk of non-communicable chronic disease and mortality: a systematic review and dose-response meta-analysis of prospective cohort studies

We aimed to investigate the association between adherence to the Nordic diet (ND) and the risk of chronic disease. PubMed, Scopus, and ISI Web of Science were searched to February 2020 to find prospective cohort studies. The relative risks (RRs) were calculated using a fixed-effects/random-effects model. The certainty of evidence was rated using the GRADE approach. Thirteen prospective cohort studies with 930,153 participants were included. The RRs for the highest compared to the lowest category of adherence to the ND were 0.78 (95%CI: 0.69, 0.87; I² = 51%, n = 6) for all-cause mortality, 0.78 (95%CI: 0.74, 0.83; I² = 70%, n = 4) for cardiovascular mortality, 0.86 (95%CI: 0.80, 0.93; I² = 83%, n = 4) for cancer mortality, 0.88 (95%CI: 0.79, 0.98; I² = 3%, n = 3) for stroke, 0.80 (95%CI: 0.68, 0.95; I² = 47%, n = 3) for myocardial infarction, and 0.90 (95%CI: 0.82, 0.99; I² = 33%, n = 4) for type 2 diabetes. There was an inverse linear association between the ND score and the risk of mortality, and an inverse monotonic association for type 2 diabetes. The certainty in the estimates ranged from very low to low.

Recommended Food Score and Healthy Nordic Food Index in Cancer: A Systematic Review

Aim: Cancer is the second leading cause of death in the world. About one third of deaths from cancer are due to the five behavioral and dietary risk factors e.g., high body mass index, low fruit and vegetable consumption, lack of physical activity, tobacco use, and alcohol use. The aim of this study is to review systematically the association of Recommended Food Score (RFS) and the Healthy Nordic Food Index (HNFI) with cancer.Method: Literature search conducted using electronic database PubMed, Google scholar, Science direct for the period of 2011 until January 2020 also reference list of the included studies.Results: Nine studies were met inclusion criteria. Two studies that investigated about RFS showed no significant association between RFS and breast cancer and colorectal cancer survival. Two out of three studies aboutthe HNFI and colorectal cancer observed that adherence to the HNFI might decrease colorectal cancer incidence and improve colorectal cancer survival. In addition, two out of three studies showed adherence to the HNFI could decrease cancer mortality.Conclusion: Adherence to the HNFI might decrease the risk of colorectal cancer incidence. It is suggested more studies about between RFS and THE HNFI with other kind of cancers.

Healthy dietary patterns and risk and survival of breast cancer: a meta-analysis of cohort studies

PURPOSES

Dietary patterns have been found to be associated with the overall cancer risk and survival. However, the associations of healthy dietary patterns and breast cancer remain unclear. We aimed to conduct a meta-analysis of prospective cohort studies to estimate the pooled results of the association of healthy dietary patterns with breast cancer risk and survival.

METHODS

PubMed, EMBASE, and Web of Science were searched for literature published until June 24th, 2018 that examined the associations between healthy dietary patterns and breast cancer risk and survival. Risk ratios (RRs) and 95% confidence intervals (CIs) were calculated by using a random-effects model for meta-analysis.

RESULTS

There were 32 articles retrieved for the meta-analysis, with 27 for breast cancer risk and five for breast cancer survival. There was a statistically significant lower risk of breast cancer associated with healthy dietary patterns (RR = 0.93, 95% CI: 0.88, 0.98). Subgroup analysis results suggested that there was an inverse association between breast cancer risk and posterori-derived healthy patterns, but no statistically significant associations were found in other stratified subgroups (a priori-derived diet, study region, menopausal status, or breast cancer subtypes). Healthy dietary patterns were associated inversely with all-cause mortality (RR = 0.76, 95% CI: 0.63, 0.92); however, no association was found for breast cancer-specific mortality.

CONCLUSIONS

The results suggested that healthy dietary patterns might be associated with a reduced risk of breast cancer and all-cause mortality among breast cancer patients. It could be clinically relevant to promote healthy dietary patterns for breast cancer prevention and improve survival among breast cancer patients.

The inflammatory potential of diet in determining cancer risk; A prospective investigation of two dietary pattern scores

Purpose

Inflammation-related mechanisms may contribute to the link between diet and cancer. We sought to investigate the inflammatory impact of diet on cancer risk using the Dietary inflammatory index (DII) and an adapted Mediterranean diet score (MDS).

Methods

This population-based, prospective cohort study used self-reported dietary data from the Västerbotten Intervention Programme, including 100,881 participants, of whom 35,393 had repeated measures. Associations between dietary patterns and cancer risk were evaluated using Cox proportional hazards regression. We also used restricted cubic splines to test for potential non-linear associations.

Results

A total of 9,250 incident cancer cases were diagnosed during a median follow-up of 15 years. The two dietary patterns were moderately correlated to each other and had similar associations with cancer risk, predominantly lung cancer in men (DII per tertile decrease: Hazard ratio (HR) 0.81 (0.66–0.99), MDS per tertile increase: HR 0.86 (0.72–1.03)), and gastric cancer in men (DII: 0.73 (0.53–0.99), MDS: 0.73 (0.56–0.96)). Associations were, in general, found to be linear. We found no longitudinal association between 10-year change in diet and cancer risk.

Conclusion

We confirm small, but consistent and statistically significant associations between a more anti-inflammatory or healthier diet and reduced risk of cancer, including a lower risk of lung and gastric cancer in men. The dietary indexes produced similar associations with respect to the risk of cancer.

Nordic diet, Mediterranean diet, and the risk of chronic diseases: the EPIC-Potsdam study

BACKGROUND

The Mediterranean Diet (MedDiet) has been acknowledged as a healthy diet. However, its relation with risk of major chronic diseases in non-Mediterranean countries is inconclusive. The Nordic diet is proposed as an alternative across Northern Europe, although its associations with the risk of chronic diseases remain controversial. We aimed to investigate the association between the Nordic diet and the MedDiet with the risk of chronic disease (type 2 diabetes (T2D), myocardial infarction (MI), stroke, and cancer) in the EPIC-Potsdam cohort.

METHODS

The EPIC-Potsdam cohort recruited 27,548 participants between 1994 and 1998. After exclusion of prevalent cases, we evaluated baseline adherence to a score reflecting the Nordic diet and two MedDiet scores (tMDS, reflecting the traditional MedDiet score, and the MedPyr score, reflecting the MedDiet Pyramid). Cox regression models were applied to examine the association between the diet scores and the incidence of major chronic diseases.

RESULTS

During a follow-up of 10.6 years, 1376 cases of T2D, 312 of MI, 321 of stroke, and 1618 of cancer were identified. The Nordic diet showed a statistically non-significant inverse association with incidence of MI in the overall population and of stroke in men. Adherence to the MedDiet was associated with lower incidence of T2D (HR per 1 SD 0.93, 95% CI 0.88-0.98 for the tMDS score and 0.92, 0.87-0.97 for the MedPyr score). In women, the MedPyr score was also inversely associated with MI. No association was observed for any of the scores with cancer.

CONCLUSIONS

In the EPIC-Potsdam cohort, the Nordic diet showed a possible beneficial effect on MI in the overall population and for stroke in men, while both scores reflecting the MedDiet conferred lower risk of T2D in the overall population and of MI in women.

Adherence to the Western, Prudent and Mediterranean dietary patterns and breast cancer risk: MCC-Spain study

OBJECTIVE

To externally validate the previously identified effect on breast cancer risk of the Western, Prudent and Mediterranean dietary patterns.

STUDY DESIGN

MCC-Spain is a multicase-control study that collected epidemiological information on 1181 incident cases of female breast cancer and 1682 healthy controls from 10 Spanish provinces. Three dietary patterns derived in another Spanish case-control study were analysed in the MCC-Spain study. These patterns were termed Western (high intakes of fatty and sugary products and red and processed meat), Prudent (high intakes of low-fat dairy products, vegetables, fruits, whole grains and juices) and Mediterranean (high intake of fish, vegetables, legumes, boiled potatoes, fruits, olives, and vegetable oil, and a low intake of juices). Their association with breast cancer was assessed using logistic regression models with random province-specific intercepts considering an interaction with menopausal status. Risk according to tumour subtypes - based on oestrogen (ER), progesterone (PR) and human epidermal growth factor 2 (HER2) receptors (ER+/PR+ & HER2-; HER2+; ER-/PR- & HER2-) - was evaluated with multinomial regression models.

MAIN OUTCOME MEASURES

Breast cancer and histological subtype.

RESULTS

Our results confirm most of the associations found in the previous case-control study. A high adherence to the Western dietary pattern seems to increase breast cancer risk in both premenopausal women (OR₄^th_vs.1^st_quartile (95% CI):1.68 (1.02;2.79); OR_1SD-increase (95% CI):1.19 (1.02;1.40)) and postmenopausal women (OR₄^th_vs.1^st_quartile(95% CI):1.48(1.07;2.05); OR_1SD-increase(95% CI): 1.14 (1.01;1.29)). While high adherence to the Prudent pattern did not show any effect on breast cancer, the Mediterranean dietary pattern seemed to be protective, but only among postmenopausal women (OR₄^th_vs.1^st_quartile (95% CI): 0.72 (95% CI 0.53;0.98); p-int=0.075). There were no significant differences by tumour subtype.

CONCLUSION

Dietary recommendations based on a departure from the Western dietary pattern in favour of the Mediterranean diet could reduce breast cancer risk in the general population.

Are self-reported unhealthy food choices associated with an increased risk of breast cancer? Prospective cohort study using the British Food Standards Agency nutrient profiling system

OBJECTIVES

French authorities are considering the implementation of a simplified nutrition labelling system on food products to help consumers make healthier food choices. One of the most documented candidates (Five-Colour Nutrition Label/Nutri-score) is based on the British Food Standards Agency Nutrient Profiling System (FSA-NPS), a score calculated for each food/beverage using the 100 g amount of energy, sugar, saturated fatty acid, sodium, fibres, proteins, and fruits and vegetables. To assess its potential public health relevance, studies were conducted on the association between the nutritional quality of the diet, measured at the individual level by an energy-weighted mean of all FSA-NPS scores of foods usually consumed (FSA-NPS dietary index (FSA-NPS DI)), and the risk of chronic diseases. The present study aimed at investigating the relationship between the FSA-NPS DI and breast cancer risk.

DESIGN

Prospective study.

SETTING

Population based, NutriNet-Santé cohort, France.

PARTICIPANTS

46 864 women aged ≥35 years who completed ≥3 24-hour dietary records during their first 2 year of follow-up.

PRIMARY OUTCOME MEASURE

Associations between FSA-NPS DI and breast cancer risk (555 incident breast cancers diagnosed between 2009 and 2015) were characterised by multivariable-adjusted Cox proportional hazard models.

RESULTS

A higher FSA-NPS DI (lower nutritional quality of the diet) was associated with an increased breast cancer risk (HR_{1-point increment}=1.06 (1.02-1.11), p=0.005; HR_Q5vs.Q1=1.52 (1.11-2.08), p trend=0.002). Similar trends were observed in premenopausal and postmenopausal women (HR_{1-point increment}=1.09 (1.01-1.18) and 1.05 (1.00-1.11), respectively).This study was based on an observational cohort using self-reported dietary data, thus residual confounding cannot be entirely ruled out. Finally, this holistic approach does not allow investigating which factors in the diet most specifically influence breast cancer risk.

CONCLUSIONS

These results suggested that unhealthy food choices, as characterised by the FSA-NPS, may be associated with an increase in breast cancer risk, supporting the potential public health relevance of using this profiling system in the framework of public health nutritional measures.

Adherence to a Healthy Nordic Diet and Risk of Stroke: A Danish Cohort Study

BACKGROUND AND PURPOSE

Specific dietary patterns, including the Mediterranean diet, have been associated with stroke prevention. Our aim was to investigate whether adherence to a healthy Nordic diet, including fish, apples and pears, cabbages, root vegetables, rye bread, and oatmeal, was associated with risk of stroke.

METHODS

Incident cases of stroke among 55 338 men and women from the Danish Diet, Cancer and Health cohort were identified from the Danish National Patient Register and verified by review of records. Cases of ischemic stroke were further subclassified based on etiology according to the TOAST classification system (Trial of Org 10172 in Acute Stroke Treatment). Information on diet was collected at baseline (1993-1997) using a semiquantitative food-frequency questionnaire. Cox proportional hazards models were used to estimate hazards ratios of total stroke and subtypes of ischemic and hemorrhagic stroke.

RESULTS

During a median follow-up of 13.5 years, 2283 cases of incident stroke were verified, including 1879 ischemic strokes. Adherence to a healthy Nordic diet, as reflected by a higher Healthy Nordic Food Index score, was associated with a lower risk of stroke. The hazards ratio comparing an index score of 4 to 6 (high adherence) with an index score of 0 to 1 (low adherence) was 0.86 (95% confidence interval 0.76-0.98) for total stroke. Inverse associations were observed for ischemic stroke, including large-artery atherosclerosis. No trend was observed for hemorrhagic stroke; however, a statistically insignificant trend was observed for intracerebral hemorrhage.

CONCLUSIONS

Our findings suggest that a healthy Nordic diet may be recommended for the prevention of stroke.

Food quality score and the risk of coronary artery disease: a prospective analysis in 3 cohorts

BACKGROUND

Currently, there are few diet quality assessment tools that are predictive of coronary artery disease (CAD) risk that do not require nutrient analysis and substantial time to administer in clinical settings.

OBJECTIVE

To inform the development of such a tool, we prospectively examined the association between a food-based diet quality score and risk of CAD in 3 separate large US cohort studies.

DESIGN

Between 1984 and 2012, 71,415 women (aged 43-63 y in 1984), 42,945 men (aged 40-75 y in 1986), and 93,131 younger women (aged 27-44 y in 1991) without a history of cardiovascular disease were followed up to 28 y. Diet was assessed ≤7 times by using repeated food-frequency questionnaires. We computed the Food Quality Score (FQS) for each individual based on food groups previously associated with less weight gain. A higher score represented a healthier diet. The FQS and CAD association was modeled with the Cox proportional hazard model, controlling for potential confounders. We also compared the magnitude of association with CAD for the FQS and other diet quality scores.

RESULTS

We ascertained 6817 incident total CAD events, with 4588 cases of nonfatal myocardial infarction and 2131 fatal CAD events. Comparing top to bottom deciles, pooled RRs of the FQS were 0.61 (95% CI: 0.54, 0.69; P-trend < 0.001) for total CAD. These associations were independent of established cardiovascular disease risk factors including body weight, physical activity, and smoking. The magnitude of the RR for 1 SD of the FQS and CAD was generally similar to established diet scores that require detailed nutrient analysis, including the Alternate Healthy Eating Index-2010, the Dietary Approaches to Stop Hypertension score, and the alternate Mediterranean diet score.

CONCLUSION

A higher food-based diet quality score was associated with lower risk of CAD and was comparable with established diet scores.

The association between adherence to the New Nordic Diet and diet quality

BACKGROUND

Previous studies have reported a positive association between scoring on healthy Nordic diet scales and the intake of healthy foods and nutrients, and also with higher intake of meat, sweets, cakes, and energy in general. These studies have used the same food frequency questionnaire (FFQ) responses for constructing the diet score as for calculating intakes of foods and nutrients. Thus, it is not clear whether the coexistence of healthy and less healthy dietary aspects among adherers to Nordic diets would occur even though separate methods were applied for exploring these relations.

OBJECTIVE

To assess the association between adherence to the New Nordic Diet (NND), derived from an FFQ, and diet quality, determined from two 24-h dietary recall interviews.

DESIGN

In total, 65 parents of toddlers in Southern Norway answered the NND FFQ and two 24-h dietary recall interviews. NND adherence was determined from the FFQ and categorized into low, medium, and high adherence. The two 24-h recalls provided data for the intake of specific foods and nutrients, selected on the basis of the Norwegian food-based guidelines as an indicator of a healthy diet. The Kruskal-Wallis test was used for assessing differences in food and nutrient intake across NND groups.

RESULTS

High NND adherence derived from FFQ was associated with a high intake of fruits (p=0.004) and fiber (p=0.02), and a low intake of meat (p=0.004) and margarines (p=0.05), derived from recalls. A larger proportion of high NND adherers (68%) complied with the national dietary recommendation targeting meat intake compared with low NND adherers (29%) (p=0.04).

CONCLUSION

The present study showed that higher NND adherence measured with FFQ was associated with a higher intake of selected healthy foods and nutrients, measured with recalls. However, a higher intake of meat, sweets, and energy, as earlier reported, was not observed.