Carbohydrate quality index and breast cancer risk in a Mediterranean cohort: The SUN project

Macronutrient quality and its association with micronutrient adequacy in children

BACKGROUND & AIMS

The double burden of malnutrition compels us to reconsider macronutrients from a diet quality perspective. The Macronutrient Quality Index (MQI) has been designed to reflect overall macronutrient quality and is based on three sub-indexes: the carbohydrate quality index (CQI), the healthy plate protein quality index (HPPQI) and the fat quality index (FQI). Nutritional adequacy is an essential aspect of diet quality that should be captured by reliable dietary indexes.

METHODS

We analyzed the association between the Macronutrient Quality Index (MQI) and micronutrient adequacy. Participants were children aged 4 and 5 years, recruited in the SENDO cohort. Baseline information was collected through a self-administered online questionnaire, which included information on sociodemographic, dietary, and lifestyle variables. Dietary information was obtained using a 147-item validated semi-quantitative food frequency questionnaire. Participants were categorized into tertiles based on their MQI score. We evaluated the intake of 20 micronutrients and assessed the probability of micronutrient adequacy using the Estimated Average Requirement cut-off point.

RESULTS

Children in the highest tertile of MQI had 0.33-fold lower odds (95%CI 0.17-0.66) of having ≥3 inadequate micronutrient intakes than their peers in the lowest tertile, after adjusting for potential confounders. The adjusted proportions of children with inadequate intake of ≥3 micronutrients were 18%, 14% and 11% in the first, second, and third tertiles of MQI respectively. The MQI appears to be capable of capturing nutrient adequacy in children, although our results suggest that a modified MQI, with eggs and dairy products weighted positively, might be more adequate for the pediatric population.

Dietary carbohydrate quality index and incidence of obesity-related cancers in the "Seguimiento Universidad De Navarra" (SUN) prospective cohort

PURPOSE

The quality, rather than the quantity, of carbohydrate intake may play a major role in the etiology of obesity-related cancers (ORCs). We assessed the association between a previously defined carbohydrate quality index (CQI) and the risk of developing ORCs in the "Seguimiento Universidad de Navarra" (SUN) cohort.

METHODS

A total of 18,446 Spanish university graduates [mean age 38 years (SD 12 years), 61% women, mean BMI 23.5 kg/m2 (SD 3.5 kg/m2)], with no personal history of cancer, were followed-up. Baseline CQI was assessed summing quintiles of four previously defined criteria: high dietary fiber intake, low glycemic index (GI), high whole-grain: total-grain carbohydrates ratio and high solid carbohydrates: total carbohydrates ratio. Participants were classified into tertiles of their total CQI. Incident ORCs were confirmed by an oncologist using medical records and by querying the National Death Index blindly to dietary exposures.

RESULTS

During a median follow-up of 13.7 years, 269 incident cases of ORC were confirmed. A higher CQI was inversely associated with ORC incidence [multivariable-adjusted hazard ratio (HR) for the upper (T3) versus the lowest tertile (T1) of 0.68 (95% CI: 0.47-0.96), p for trend = 0.047]. Particularly, higher dietary fiber intake was inversely associated with ORC, HRT3 vs. T1=0.57 (95% CI 0.37-0.88 p for trend = 0.013).

CONCLUSION

In this prospective Mediterranean cohort, an inverse association between a better global quality of carbohydrate intake and the risk of ORCs was found. Strategies for cancer prevention should promote a higher quality of carbohydrate intake.

Carbohydrate quality indices and lung cancer risk: a case-control study from Iran

Considering that carbohydrates play an important role in supplying the body with energy and exhibit diverse mechanisms that can either prevent or stimulate cancer, we hypothesize that the quality of carbohydrate intake may be associated with cancer risk, including lung cancer. This hospital-based case-control study was conducted on 135 newly diagnosed lung cancer patients, and 237 healthy age- and sex-matched hospitalized controls. We used a valid and reliable 148-item Food Frequency Questionnaire to collect the dietary intake of subjects. Multivariate logistic regression was used to estimate the association between carbohydrate quality indices and the odds of lung cancer. After adjustment for confounding variables, the high glycemic index appears to be an increased risk factor for lung cancer [odds ratio (OR) = 2.51, 95% confidence interval (CI): 1.28-4.91]. No statistically significant association was found between glycemic load and lung cancer (OR = 2.51, 95% CI: 0.98-6.43). In contrast, the carbohydrate quality index (OR = 0.23, 95% CI: 0.11-0.48) and low-carbohydrate diet score (OR = 0.17, 95% CI: 0.08-0.36), were associated with a decrease in the risk of lung cancer. In summary, our study showed that a high glycemic index is a risk factor for lung cancer, however carbohydrate quality index and low-carbohydrate diet score is a dietary approach to reduce the risk of lung cancer.

Associations between dietary macronutrient quality and asthenozoospermia risk: a hospital-based case-control study

Background & aims: Macronutrients are the main part of the human diet and can affect multiple health outcomes. Nevertheless, associations between dietary macronutrient quality and asthenozoospermia risk have not been reported to date. Thus, this study aimed to be the first to explore the associations between macronutrient quality and asthenozoospermia risk using the novel multidimensional macronutrient quality index (MQI). Methods: A case-control study was conducted at infertility clinics of Shengjing Hospital of China Medical University during June and December 2020, including 552 asthenozoospermia cases and 585 normozoospermia controls. Data on diet were collected using a validated food frequency questionnaire. MQI was estimated according to the carbohydrate quality index (CQI), fat quality index (FQI), and protein quality index (PQI). Binary logistic regression models were performed to calculate the odds ratio (OR) with a 95% confidence interval (CI). Subgroup and interaction analyses were performed based on age, body mass index, physical activity, smoking, drinking, and education level. Dose-response relationships were evaluated by restricted cubic splines. Sensitivity analyses were performed in two ways. First, participants with a dietary change were excluded to lower potential reverse causation. Then, we used the healthy plate protein source quality index instead of PQI to redefine MQI. Results: No statistically significant association was observed between dietary MQI and asthenozoospermia risk (OR = 1.24, 95% CI: 0.88-1.73). The sub-indices of MQI, CQI, FQI, and PQI, failed to be identified as having a statistically significant association with asthenozoospermia risk (OR = 1.35, 95% CI: 0.92-1.97 for CQI; OR = 1.13, 95% CI: 0.84-1.53 for FQI; OR = 1.28, 95% CI: 0.92-1.78 for PQI). However, CQI showed a positive association with the risk of asthenozoospermia among non-drinkers (Ptrend < 0.05) and highly educated participants (OR = 1.82, 95% CI: 1.13-2.94; Ptrend < 0.05). Additionally, there was a multiplicative interaction between CQI and education level for asthenozoospermia risk (P < 0.05). Conclusions: Our findings demonstrated no association of MQI and its sub-indices with asthenozoospermia risk except for CQI. Although our findings are mostly non-significant, they contribute novel knowledge to this research field and lay the foundation for future studies.

The TEOGIC study project: a comprehensive characterization of early onset gastrointestinal cancer in the Northern area of Spain

BACKGROUND

Gastrointestinal cancers represent one of the most prevalent diseases worldwide. Strikingly, the incidence of Early Onset Gastrointestinal Cancer (EOGIC) has been rising during the last decades and changes in lifestyle and environmental exposure seem to play a role. EOGIC has been defined as a different entity compared to on-average gastrointestinal cancer, with distinct clinical and molecular characteristics. Inherent to the particularities of younger age, there is an unmet need for a tailored approach for the management of these patients. The TEOGIC proposes a comprehensive study to characterize EOGIC patients in the northern of Spain.

METHODS

Patients with histologically confirmed new diagnosis of colorectal, gastroesophageal and pancreatic adenocarcinoma will be considered for two cohorts: EOGIC (≤ 50 years old) and non-EOGIC (60-75 years old), with a ratio of 1:2. Two hundred and forty patients will be recruited in 4 Public Hospitals from northern Spain. After receiving unified informed consent, demographic and clinical data of the patients will be collected in a REDCap database. Lifestyle related data will be obtained in questionnaires assessing diet, physical activity and the general quality of life of the patients before diagnosis. Biological samples prior to any onco-specific treatment will be obtained for the analyses of circulating inflammatory proteins, gut microbiota, and the proteome of the tumor microenvironment. Histologic characteristics and routine biomarkers will be also collected. Thereafter, data will be integrated and analyzed to assess tumor specific, pan-tumor and sex-associated differential characteristics of EOGIC.

DISCUSSION

The underlying risk factors and differential characteristics of EOGIC remain poorly studied, particularly in our geographical area. Although limited by the exploratory nature and the small sample size estimated to be recruited, TEOGIC represents the first attempt to comprehensively characterize these young patients, and thus attend to their special needs. Findings derived from this study could contribute to raise awareness and preventive behaviors in the population. In parallel, molecular studies could lead to the identification of potential novel non-invasive biomarkers and therapeutic targets that would help in the development of the tailored clinical management of these patients, focusing on screening programs for early diagnosis and precision medicine.

Carbohydrate quality, not quantity, linked to reduced colorectal cancer incidence and mortality in US populations: evidence from a prospective study

BACKGROUND

Carbohydrates have been implicated in colorectal cancer (CRC) risk, but the specific impact of carbohydrate quality and quantity on CRC susceptibility in US populations remains unclear.

METHODS

We followed 101,694 participants from Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. The carbohydrate quality index (CQI) and low-carbohydrate diet score (LCDs) were used to evaluate the daily carbohydrate quality and quantity separately, where higher scores indicated greater adherence. Cox proportional hazards regression was used to compute HRs and 95% CIs for incident CRC and related death. Subgroup analyses were conducted to identify potential effect modifiers.

RESULTS

During follow-up, we documented 1085 incident cases of CRC, of whom 311 died from CRC. Individuals in the highest compared with the lowest quartiles of CQI had a lower CRC incidence (Q4 vs Q1: HR 0.80, 95% CI 0.67-0.96, Ptrend = 0.012) and mortality (Q4 vs Q1: HR 0.61, 95% CI 0.44-0.86, Ptrend = 0.004). The inverse association between CQI and CRC risk was observed for distal colon and rectum but not for proximal colon cancer. Regarding mortality, this association was only significant for rectum cancer. Subgroup analyses indicated this inverse association of CQI with CRC risk was only observed in participants with lower LCDs. No significant associations were found between LCDs and CRC incidence or mortality.

CONCLUSIONS

Our findings suggest focusing on higher quality, rather than restricting the quantity, of carbohydrate consumption may be an effective approach to reduce the risk of CRC in the US population, particularly for distal colon and rectal cancers.

High-protein diet scores, macronutrient substitution, and breast cancer risk: insights from substitution analysis

BACKGROUND

Evidence from recent studies suggested that variation in the quantity and quality of macronutrients in the diet may potentially play a role in predicting the risk of breast cancer (BC). In the current study, we aimed to assess the association of different high-protein diet scores and replacing fats and carbohydrate (CHO) with protein in the diet with the BC risk among Iranian women.

METHODS

The current hospital-based case-control study was conducted on 401 participants, aged ≥ 30 years old, including 134 women in the case group who had been diagnosed with histologically confirmed BC and 267 women in the control group. Dietary intake data was collected using a validated food frequency questionnaire, and high protein diet scores were determined. Logistic regression models were used to determine the odds ratios (OR) and 95% confidence interval (CI) of BC across tertiles of high protein diet scores. Also, we assessed how substituting protein with other macronutrients affected BC odds while adjusting for the various confounding variables.

RESULTS

Participants' mean ± SD of age and body mass index were 47.9 ± 10.3 years and 29.4 ± 5.5 kg/m2, respectively. The scores of high-protein-low-CHO and fat diet, high-protein and CHO-low-fat diet, and high-protein and fat-low-CHO diet in participants were 16.5 ± 3.8, 16.5 ± 6.7, and 16.4 ± 5.9, respectively. In the multivariable model, individuals in the highest tertile of high-protein-low-CHO and fat diet score (OR:0.71;95%CI:0.56-0.90) and high-protein and CHO-low-fat diet (OR:0.76;95%CI:0.60-0.97) had lower odds of BC compared to those in the lowest tertile (P < 0.05). However, no significant association was found between high-protein and fat-low-CHO diet and BC risk. Our results showed that replacing fat by protein (ORdifferences:-0.40;95%CI:-0.73,-0.07) and also replacing refined-CHO by plant protein (ORdifferences:-0.66;95%CI:-1.26,-0.07) in the diet are associated inversely with risk of BC(P < 0.05).

CONCLUSIONS

The results of our study suggested that higher adherence to a high-protein-low-CHO and fat diet, characterized by a higher intake of plant proteins and a lower intake of refined grains and saturated fat can play a protective role against the odds of BC.

Dietary Approach of Patients with Hormone-Related Cancer Based on the Glycemic Index and Glycemic Load Estimates

Hormone-related cancers, namely breast, endometrial, cervical, prostate, testicular, and thyroid, constitute a specific group of cancers dependent on hormone levels that play an essential role in cancer growth. In addition to the traditional risk factors, diet seems to be an important environmental factor that partially explains the steadily increased prevalence of this group of cancer. The composition of food, the dietary patterns, the endocrine-disrupting chemicals, and the way of food processing and preparation related to dietary advanced glycation end-product formation are all related to cancer. However, it remains unclear which specific dietary components mediate this relationship. Carbohydrates seem to be a risk factor for cancer in general and hormone-related cancers, in particular, with a difference between simple and complex carbohydrates. Glycemic index and glycemic load estimates reflect the effect of dietary carbohydrates on postprandial glucose concentrations. Several studies have investigated the relationship between the dietary glycemic index and glycemic load estimates with the natural course of cancer and, more specifically, hormone-related cancers. High glycemic index and glycemic load diets are associated with cancer development and worse prognosis, partially explained by the adverse effects on insulin metabolism, causing hyperinsulinemia and insulin resistance, and also by inflammation and oxidative stress induction. Herein, we review the existing data on the effect of diets focusing on the glycemic index and glycemic load estimates on hormone-related cancers.

The association of macronutrient quality and its interactions with energy intake with survival among patients with ovarian cancer: results from a prospective cohort study

BACKGROUND

Emerging evidence supports shifting the focus from the quantity of macronutrients to quality to obtain greater benefits for the prognosis of ovarian cancer (OC). Additionally, despite the high relevance between macronutrient quality and quantity, the interaction of these parameters on OC survival remains unknown.

OBJECTIVE

A multidimensional macronutrient quality index (MQI) was applied to investigate the association between overall macronutrient quality and the survival of patients with OC.

METHODS

A prospective cohort study was conducted with 701 females diagnosed with OC who were enrolled from 2015 to 2020. Dietary intake information was obtained from a validated food frequency questionnaire. The MQI was calculated based on 3 quality indices: carbohydrate quality index (CQI), fat quality index (FQI), and protein quality index (PQI). Cox proportional hazards regression was conducted to calculate HRs and 95% CIs. Furthermore, we evaluated whether energy intake status (total energy intake and energy balance) modified the association between MQI and OC survival.

RESULTS

During a median follow-up period of 38 (interquartile: 35-40) mo, 130 deaths occurred. The prediagnosis high MQI scores were associated with substantially improved survival among females with OC (HR_{tertile 3 vs. tertile 1} = 0.50, 95% CI: 0.33, 0.77). For sub-indices of the MQI, higher CQI (HR = 0.60, 95% CI: 0.36, 0.99), higher FQI (HR = 0.55, 95% CI: 0.34, 0.87), and higher PQI (HR = 0.58, 95% CI: 0.35, 0.94) scores were all associated with better survival. Notably, significant interactions were observed for the MQI score with total energy intake and energy balance as well as the quantity and quality of carbohydrates on survival.

CONCLUSIONS

Intake of high-quality macronutrients before diagnosis was associated with improved survival among females with OC, especially for those with energy imbalance. Am J Clin Nutr 2023;xxx:xx-xx.

Longitudinal association of dietary carbohydrate quality with visceral fat deposition and other adiposity indicators

BACKGROUND & AIMS

The quality of dietary carbohydrates rather than total carbohydrate intake may determine the accumulation of visceral fat; however, to date, few studies have examined the impact of diet on adiposity using specific imaging techniques. Thus, the aim of this prospective study was to investigate the association between concurrent changes in carbohydrate quality index (CQI) and objectively-quantified adiposity distribution over a year.

METHODS

We analyzed a cohort of 1476 participants aged 55-75 years with overweight/obesity and metabolic syndrome (MetS) from the PREDIMED-Plus randomized controlled trial. Dietary intake information was obtained at baseline, 6- and 12-months from a validated 143-item semi-quantitative food-frequency questionnaire, and CQI (range: 4 to 20) was calculated based on four dietary criteria: total dietary fibre, glycemic index, wholegrain/total grain carbohydrate ratio, and solid/total carbohydrate ratio. Overall and regional adiposity (total body fat, visceral fat and android-to-gynoid fat ratio) was quantified using dual-energy X-ray absorptiometry at all three time points. Multiple adjusted linear mixed-effects models were used to assess associations between concurrent changes in repeatedly measured CQI and adiposity over time.

RESULTS

After controlling for potential confounding factors, a 3-point increment in CQI over 12-month follow-up was associated with a decrease in visceral fat (β -0.067 z-score, 95% CI -0.088; -0.046, p < 0.001), android-to-gynoid fat ratio (-0.038, -0.059; -0.017, p < 0.001), and total fat (-0.064, -0.080; -0.047, p < 0.001). Fibre intake and the ratio of wholegrain/total grain showed the strongest inverse associations with all adiposity indicators.

CONCLUSIONS

In this prospective cohort of older adults with overweight/obesity and MetS, we found that improvements in dietary carbohydrate quality over a year were associated with concurrent favorable changes in visceral and overall fat deposition. These associations were mostly driven by dietary fibre and the wholegrain/total grain ratio.

TRIAL REGISTRATION

The trial was registered at the International Standard Randomized. CONTROLLED TRIAL: (ISRCTN: http://www.isrctn.com/ISRCTN89898870) with number 89898870 and registration date of 24 July 2014, retrospectively registered.

Vitamin D and Risk of Obesity-Related Cancers: Results from the SUN (‘Seguimiento Universidad de Navarra’) Project

Obesity is associated with a higher risk of several types of cancer, grouped as obesity-related cancers (ORC). Vitamin D deficiency is more prevalent in obese subjects, and it has been suggested to play a role in the association between obesity and cancer risk. The aim of the study was to analyze the association between vitamin D intake and the subsequent risk of ORC in a prospective Spanish cohort of university graduates. The SUN Project, initiated in 1999, is a prospective dynamic multipurpose cohort. Participants answered a 556-item lifestyle baseline questionnaire that included a validated food-frequency questionnaire. We performed Cox regression models to estimate the hazard ratios (HRs) of ORC according to quartiles of energy-adjusted vitamin D intake (diet and supplements). We included 18,017 participants (mean age = 38 years, SD = 12 years), with a median follow-up of 12 years. Among 206,783 person-years of follow-up, we identified 225 cases of ORC. We found no significant associations between vitamin D intake and ORC risk after adjusting for potential confounders: HR_Q2vsQ1 = 1.19 (95% CI 0.81–1.75), HR_Q3vsQ1 = 1.20 (95% CI 0.81–1.78), and HR_Q4vsQ1 = 1.02 (95% CI 0.69–1.51). Dietary and supplemented vitamin D do not seem to be associated with ORC prevention in the middle-aged Spanish population.

Association between pre-conceptional carbohydrate quality index and the incidence of gestational diabetes: the SUN cohort study

The aim of the study was to investigate the association between pre-gestational carbohydrate quality index (CQI) and the incidence of gestational diabetes mellitus (GDM). Data from the 'Seguimiento Universidad de Navarra' (SUN) cohort were used, which includes 3827 women who notified at least one pregnancy between December 1999 and December 2019. We used a validated semi-quantitative 136-item FFQ to evaluate dietary exposures at baseline and at 10-year follow-up. The CQI was defined by four criteria: glycaemic index, whole-grain/total-grain carbohydrate, dietary fibre intake and solid/total carbohydrate ratio. We fitted generalised estimating equations with repeated measurements of the CQI to assess its relationship with incident GDM. A total of 6869 pregnancies and 202 new cases of incident GDM were identified. The inverse association between the global quality of carbohydrate and the development of GDM was not statistically significant: OR the highest v. the lowest CQI category: 0·67, 95 % CI (0·40, 1·10), Pfor trend = 0·10. Participants at the highest CQI category and with daily carbohydrate amounts ≥50 % of total energy intake had the lowest incidence of GDM (OR = 0·29 (95 % CI (0·09, 0·89)) compared with those with the lowest quality (lowest CQI) and quantity (≤40 %). Further studies are needed to overcome the limitations of our study. Those studies should jointly consider the quality and the quantity of dietary carbohydrates, as the quality might be of importance, especially in women with a higher intake of carbohydrates.

Dietary glycemic index, glycemic load and cancer risk: a meta-analysis of prospective cohort studies

PURPOSE

There is considerable inconsistency in results regarding the association of dietary glycemic index (GI) and glycemic load (GL) with cancer risk. We therefore conducted this systematic review and dose-response meta-analysis of prospective cohort studies to evaluate the relationship between dietary GI/GL and cancer risk.

METHODS

We searched PubMed and Web of Science for prospective cohort studies of dietary GI/GL in relation to risks of all types of cancer up to 31 March 2021. We used a random-effect model to calculate summary relative risks (RR) and 95% confidence intervals (CI). The certainty of evidence was assessed by the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. This study was registered at PROSPERO (CRD42020215338).

RESULTS

Overall, 55 cohorts were included in the meta-analysis. We assessed the relationship between dietary GI or GL and risks of 23 cancer types, including hormone-related cancers, cancers from digestive system, respiratory system, urinary system and other cancer sites. High GI diet increased overall risk of cancer with low certainty of evidence (highest vs lowest categories, n = 3, RR 1.04, 95% CI 1.01-1.07). For site-specific cancers, high GI diet increased risks of lung cancer (highest vs lowest categories, n = 5, RR 1.08, 95% CI 1.01-1.18) and breast cancer (highest vs lowest categories, n = 14, RR 1.05, 95% CI 1.01-1.09), especially for postmenopausal breast cancer (highest vs lowest categories, n = 10, RR 1.06, 95% CI 1.00-1.13), all with low certainty of evidence. Additionally, dietary GI was positively related to risk of bladder cancer with low certainty of evidence (highest vs lowest categories, n = 3, RR 1.23, 95% CI 1.09-1.40), as well as negatively related to ovarian cancer risk with very low certainty of evidence (highest vs lowest categories, n = 4, RR 0.83, 95% CI 0.69-1.00) and lymphoma risk with low certainty of evidence (highest vs lowest categories, n = 2, RR 0.84, 95% CI 0.72-0.98). Besides, we found an inverse association of dietary GL with lung cancer risk with low certainty of evidence (highest vs lowest categories, n = 5, RR 0.87, 95% CI 0.80-0.94).

CONCLUSION

High dietary GI increased overall cancer risk with low certainty of evidence. For site-specific cancers, high GI diet increased the risks of breast cancer with low certainty of evidence and lung cancer with low certainty of evidence. Dietary GL was inversely associated with lung cancer risk with low certainty of evidence.

Dietary carbohydrate quality and risk of breast cancer among women

Background

A few studies have examined the relationship between carbohydrate quality index (CQI) and risk of breast cancer (BC) among women in Middle Eastern countries. We studied the associations between carbohydrate quality index and the risk of BC in overall and by menopausal status.

Methods

In this case-control study, dietary intake of 461 women with pathologically confirmed BC within the past year were examined. The same information were collected for 495 apparently healthy controls using a 168-item validated FFQ. Carbohydrate quality was determined by considering four criteria including: ratio of solid carbohydrates to total carbohydrates, dietary fiber intake, GI and the ratio of whole grains to total grains.

Results

Mean GI and GL of participants were totally 57.5 ± 7.2 and 245.7 ± 64.7, respectively. A trend toward significant association was seen between GI and odds of BC in the whole population; such that after stratifying analysis by menopausal status, premenopausal women in the highest quartile of GI were 1.85 times higher likely to have BC than those in the lowest quartile (95% CI: 1.12, 3.07, P = 0.01). We found that women with the greatest CQI had lower odds for BC, compared with those with the lowest CQI (0.63; 95% CI: 0.43–0.94, P = 0.03). This association was remained after stratifying analysis by menopausal status in premenopausal (0.55; 95% CI: 0.34–0.90, P = 0.04).

Conclusion

We found that GI was directly and CQI inversely associated with odds of BC. In order to determine the effects of dietary carbohydrate quality prospective cohort studies are needed.

Food Quality Score and Risk of Breast Cancer among Iranian Women: Findings from a Case Control Study

The quality of foods we consume may be an important risk factor for breast cancer (BrCa); however, relations between quality of food metrics and BrCa risk have not been systematically investigated. The purpose of this study was to examine the association between food quality score (FQS) by assessing the intake of healthy and unhealthy food and the odds of (BrCa) among Iranian women. This hospital-based case-control study was carried out on 150 women with pathologically confirmed breast cancer within the past three months and 150 healthy controls that were age-match from the Cancer Research Center, Imam Khomeini hospital, Iran. Participants were interviewed to obtain data relating to diet (using a 147-item validated FFQ) and BrCa risk factors. We found a significant association between adherence to the FQS and odds of breast cancer in the fully adjusted model (OR: 0.58; P = 0.04) and in premenopausal women in the fully adjusted model (OR: 0.45; P = 0.02); however, we did not observe any association between postmenopausal women in the adjusted model (OR: 0.76; P = 0.5). We also failed to observe any association between healthy (p = 0.3) and unhealthy subgroups (p = 0.3) of FQS. Our findings suggest that adherence to FQS may be associated with an increased risk of breast cancer in crude and adjusted models in overall and premenopausal women. However, we did not see any association between FQS and BrCa risk in postmenopausal women. Prospective cohort studies are needed to confirm these findings.Supplemental data for this article is available online at https://doi.org/10.1080/01635581.2021.1957136 .

Dietary Carbohydrate Quality and Quantity and Risk of Breast Cancer among Iranian Women

OBJECTIVE

This study investigated the association between quality and quantity of carbohydrate by assessing low carbohydrates diet score (LCDS), carbohydrate quality score (CQI), glycemic index (GI), dietary glycemic load (GL), and dietary carbohydrate intake, and risk of breast cancer (BrCa) among Iranian women.

METHODS

This hospital-based case-control study was carried out in the Cancer Research Center of Imam Khomeini hospital, Iran. We included One hundred and fifty newly diagnosed BrCa cases and one hundred and fifty healthy controls in this study. Socio-demographic and dietary data and anthropometric measures were recorded.

RESULTS

We found that a higher CQI than a lower score was associated with a decrease in odds of BrCa (P = 0.04). After adjusting for potential confounders, we observed that CQI was not associated with BrCa development (P = 0.05). An increase in odds of BrCa among women in the highest tertiles of GL (P = 0.12), GI (P = 0.48), and dietary carbohydrate intake (P = 0.06) was seen, which was not statistically significant. There was also a non-significant lower chance of having BrCa with adherence to the LCDS (P = 0.09).

CONCLUSION

Our findings suggest that CQI was not related to BrCa risk among Iranian women. This relation deserves to be investigated in prospective studies.

Dietary calcium, vitamin D, and breast cancer risk in women: findings from the SUN cohort

PURPOSE

Epidemiological evidence concerning the relationship between calcium and vitamin D intake and breast cancer (BC) is inconclusive. Moreover, the association according to menopausal status remains unclear. We aimed to assess whether total intakes from dietary and supplemental sources of calcium and vitamin D were associated with the incidence of BC in a Mediterranean cohort.

METHODS

We prospectively evaluated the association between intakes of calcium and vitamin D and BC risk among 10,812 women in the Seguimiento Universidad de Navarra (SUN) Project, a Spanish cohort of university graduates.

RESULTS

During a mean follow-up of 10.7 years, 101 incident BC cases were confirmed. Evidence of a non-linear association between total calcium intake and BC risk was found (P_{non-linearity} = 0.011) with risk reductions associated with higher intake up to approximately 1400 mg/day. Moderate intake [Tertile 2 (T2)] of total calcium was associated with lower overall BC risk [HR for T2 vs. Tertile 1 (T1): 0.55; 95% CI 0.33-0.91] and also among postmenopausal women (HR_{T2 vs. T1} = 0.38; 95% CI 0.16-0.92). Intake of vitamin D was not associated with BC risk.

CONCLUSIONS

Our findings suggest an L-shaped association between total calcium intake and BC incidence. Moderate calcium intake may be associated with lower BC risk among overall and postmenopausal women, but not among premenopausal women. No evidence for any association between vitamin D intake and BC was found. Adherence to current guidelines recommendations for calcium intake may help to reduce BC risk.

Dietary Antioxidant Vitamins and Minerals and Breast Cancer Risk: Prospective Results from the SUN Cohort

There is growing interest in natural antioxidants and their potential effects on breast cancer (BC). Epidemiological evidence, however, is inconsistent. We prospectively evaluated the association between dietary intake of vitamins A, C, and E, selenium, and zinc and BC among 9983 female participants from the SUN Project, a Mediterranean cohort of university graduates. Participants completed a food frequency questionnaire at baseline, and biennial follow-up information about incident BC diagnosis was collected. Cases were ascertained through revision of medical charts and consultation of the National Death Index. Cox proportional hazards models were used to estimate multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CI). During an average follow-up of 11.3 years, 107 incident BC cases were confirmed. The multivariable HRs (95% CI) for BC comparing extreme tertiles of energy-adjusted dietary intakes were 1.07 (0.64–1.77; P_trend = 0.673) for vitamin A, 1.00 (0.58–1.71; P_trend = 0.846) for vitamin C, 0.92 (0.55–1.54; P_trend = 0.728) for vitamin E, 1.37 (0.85–2.20; P_trend = 0.135) for selenium, and 1.01 (0.61–1.69; P_trend = 0.939) for zinc. Stratified analyses showed an inverse association between vitamin E intake and postmenopausal BC (HR_{T3 vs. T1} = 0.35; 95% CI, 0.14–0.86; P_trend = 0.027). Our results did not suggest significant protective associations between dietary vitamins A, C, and E, selenium, or zinc and BC risk.

Association of carbohydrate quality and all-cause mortality in the SUN Project: A prospective cohort study

BACKGROUND & AIMS

Emerging evidence supports shifting the focus from carbohydrate quantity to carbohydrate quality to obtain greater health benefits. We investigated the association of carbohydrate quality with all-cause mortality using a single, multidimensional carbohydrate quality index (CQI) designed to account for multiple characteristics of carbohydrate quality.

METHODS

A prospective study was conducted among 19,083 participants in the Seguimiento Universidad de Navarra (SUN) Project, a Mediterranean cohort of middle-aged university graduates. The CQI was based on four dimensions: high total dietary fiber intake, low glycemic index, high whole-grain carbohydrate: total grain carbohydrate ratio, and high solid carbohydrate: total carbohydrate ratio.

RESULTS

During 12.2 years of median follow-up, 440 deaths were identified. We found an inverse association between the CQI and all-cause mortality. The multivariable-adjusted hazard ratio (HR) for the highest vs. the lowest tertile of the CQI was 0.70 (95% CI, 0.53-0.93; P_trend = 0.018). However, each individual dimension of the CQI was not independently associated with lower mortality risk, with HR (95% CI) between extreme tertiles as follows: 0.77 (0.52-1.14; P_trend = 0.192) for high fiber intake; 0.81 (0.59-1.12; P_trend = 0.211) for low glycemic index; 0.87 (0.69-1.11; P_trend = 0.272) for high whole-grain carbohydrate: total-grain carbohydrate ratio; and 0.81 (0.61-1.07; P_trend = 0.139) for high solid carbohydrate: total carbohydrate ratio. Our analyses remained similar after using repeated measurements of diet with updated nutritional exposures after a ten-year follow-up.

CONCLUSIONS

The CQI as a whole, but none of its individual dimensions, was associated with lower mortality. The CQI seems to comprehensively capture the combined effects of quality domains.