Bernard Srour

Consumption of ultra-processed foods and cancer risk: results from NutriNet-Santé prospective cohort

Abstract Objective To assess the prospective associations between consumption of ultra-processed food and risk of cancer. Design Population based cohort study. Setting and participants 104 980 participants aged at least 18 years (median age 42.8 years) from the French NutriNet-Santé cohort (2009-17). Dietary intakes were collected using repeated 24 hour dietary records, designed to register participants’ usual consumption for 3300 different food items. These were categorised according to their degree of processing by the NOVA classification. Main outcome measures Associations between ultra-processed food intake and risk of overall, breast, prostate, and colorectal cancer assessed by multivariable Cox proportional hazard models adjusted for known risk factors. Results Ultra-processed food intake was associated with higher overall cancer risk (n=2228 cases; hazard ratio for a 10% increment in the proportion of ultra-processed food in the diet 1.12 (95% confidence interval 1.06 to 1.18); P for trend<0.001) and breast cancer risk (n=739 cases; hazard ratio 1.11 (1.02 to 1.22); P for trend=0.02). These results remained statistically significant after adjustment for several markers of the nutritional quality of the diet (lipid, sodium, and carbohydrate intakes and/or a Western pattern derived by principal component analysis). Conclusions In this large prospective study, a 10% increase in the proportion of ultra-processed foods in the diet was associated with a significant increase of greater than 10% in risks of overall and breast cancer. Further studies are needed to better understand the relative effect of the various dimensions of processing (nutritional composition, food additives, contact materials, and neoformed contaminants) in these associations. Study registration Clinicaltrials.gov NCT03335644.

What Do People Know and Believe about Vitamin D

People have been exposed to a lot of information regarding vitamin D, with evidence suggesting that vitamin D may be involved in numerous health conditions, subsequently creating concerns about vitamin D insufficiency. As a result, what do people really know or believe about this topic? In this cross-sectional study, we assessed vitamin D-related knowledge and beliefs in 59,273 French adults (NutriNet-Santé cohort) using a specific questionnaire. Answers to this questionnaire were weighted according to the French sociodemographic distribution and compared across individual characteristics, using χ2-tests. Physicians and media were identified as key information providers. Participants did not always accurately cite vitamin D sources (e.g., 72% only for sun exposure, fatty fish: 61%) or established health effects (e.g., bone health: 62%–78%). Conversely, they mentioned incorrect sources and health effects for which there is no consensus yet (e.g., skin cancer). These findings were modulated by age/generational and socioeconomic factors. A strong inconsistency was also observed between participants’ true vitamin D status (plasma 25-hydroxyvitamin D concentration) and their opinion about it. This study, the first in Europe with such a large sample, stresses the need for simple and up-to-date supports of communication for the public and healthcare professionals regarding sources and health effects of vitamin D.

Variations of physical activity and sedentary behavior between before and after cancer diagnosis: Results from the prospective population-based NutriNet-Santé cohort.

AbstractPhysical activity (PA) but also reduced sedentary behavior may be associated with better prognosis and lower risk of recurrence in cancer patients. Our aim was to quantify the variations in PA and time spent sedentary between before and after diagnosis, relying on prospective data in French adults. We also investigated sociodemographic and lifestyle factors associated with these variations.Subjects (n = 942) were incident cancer cases diagnosed in the NutriNet-Santé cohort between 2009 and 2015. PA and sedentary behavior were prospectively collected with the 7-day short version of the IPAQ questionnaire every year since subjects’ inclusion (i.e., an average of 2 year before diagnosis). All PA and sitting time points before and after diagnosis was compared by mixed model. Factors associated with decrease in PA and increase in sitting time were investigated using logistic regressions.Overall and vigorous PA decreased after diagnosis (P = 0.006, −32.8 ± 36.8 MET-hour/week on average, in those who decreased their overall PA and P = 0.005, −21.1 ± 36.8 MET-hour/week for vigorous PA, respectively), especially in prostate (−39.5 ± 36.3 MET-hour/week) and skin (−35.9 ± 38 MET-hour/week) cancers, in men (−40.8 ± 46.3MET-hour/week), and in those professionally inactive (−34.2 ± 37.1 MET-hour/week) (all P < 0.05). Patients with higher PA level before diagnosis were more likely to decrease their PA (odds ratio [OR]: 4.67 [3.21–6.81], P < 0.0001). Overweight patients more likely to decrease moderate PA (OR: 1.45 [1.11–1.89], P = 0.006) and walking (OR: 1.30 [1.10–1.70], P = 0.04). Sitting time increased (P = 0.02, +2.44 ± 2.43 hour/day on average, in those who increased their sitting time), especially in women (+2.48 ± 2.48 hour/day), older patients (+2.48 ± 2.57 hour/day), and those professionally inactive (2.41 ± 2.40 hour/day) (all P < 0.05). Patients less sedentary before diagnosis were more likely to increase their sitting time (OR: 3.29 [2.45–4.42], P < 0.0001).This large prospective study suggests that cancer diagnosis is a key period for change in PA and sedentary behavior. It provides insights to target the subgroups of patients who are at higher risk of decreasing PA and increasing sedentary behavior after cancer diagnosis.

Dietary iron intake and breast cancer risk: modulation by an antioxidant supplementation

Experimental results suggested that iron-induced lipid peroxidation may explain the direct associations observed between red/processed meat intakes and colorectal and breast cancer risk. However, epidemiological evidence is lacking. Thus, we investigated the association between dietary iron intake and breast cancer risk, and its potential modulation by an antioxidant supplementation and lipid intake. This prospective study included 4646 women from the SU.VI.MAX trial (daily low-dose antioxidants vs. placebo). 188 incident breast cancers were diagnosed (median follow-up=12.6y). Dietary iron intake was assessed using repeated 24h dietary records. Multivariable Cox proportional hazards models were computed. Dietary iron intake was associated with an increased breast cancer risk (HRT3vs.T1=1.67 (1.02-2.71), P-trend=0.04). This association was observed in the placebo group (HRT3vs.T1=2.80 (1.42-5.54), P-trend=0.003), but not in the antioxidant-supplemented group (P-trend=0.7, P-interaction=0.1). Besides, in the placebo group, the increased breast cancer risk associated with dietary iron intake was more specifically observed in women with higher lipid intake (P-trend=0.046). These findings suggest that dietary iron intake may be associated with an increased breast cancer risk, especially in women who did not received antioxidants during the trial and who consumed more lipids. This supports the experimental results suggesting that breast cancer risk may be increased by iron-induced lipid peroxidation.

NMR metabolomic signatures reveal predictive plasma metabolites associated with long-term risk of developing breast cancer

Background Combination of metabolomics and epidemiological approaches opens new perspectives for ground-breaking discoveries. The aim of the present study was to investigate for the first time whether plasma untargeted metabolomic profiles, established from a simple blood draw from healthy women, could contribute to predict the risk of developing breast cancer within the following decade and to better understand the aetiology of this complex disease. Methods A prospective nested case-control study was set up in the Supplémentation en Vitamines et Minéraux Antioxydants (SU.VI.MAX) cohort, including 206 breast cancer cases diagnosed during a 13-year follow-up and 396 matched controls. Untargeted nuclear magnetic resonance (NMR) metabolomic profiles were established from baseline plasma samples. Multivariable conditional logistic regression models were computed for each individual NMR variable and for combinations of variables derived by principal component analysis. Results Several metabolomic variables from 1D NMR spectroscopy were associated with breast cancer risk. Women characterized by higher fasting plasma levels of valine, lysine, arginine, glutamine, creatine, creatinine and glucose, and lower plasma levels of lipoproteins, lipids, glycoproteins, acetone, glycerol-derived compounds and unsaturated lipids had a higher risk of developing breast cancer. P-values ranged from 0.00007 [odds ratio (OR)T3vsT1=0.37 (0.23-0.61) for glycerol-derived compounds] to 0.04 [ORT3vsT1=1.61 (1.02-2.55) for glutamine]. Conclusion This study highlighted associations between baseline NMR plasma metabolomic signatures and long-term breast cancer risk. These results provide interesting insights to better understand complex mechanisms involved in breast carcinogenesis and evoke plasma metabolic disorders favourable for carcinogenesis initiation. This study may contribute to develop screening strategies for the identification of at-risk women for breast cancer well before symptoms appear.

Sociodemographic and economic factors are associated with weight gain between before and after cancer diagnosis: results from the prospective population-based NutriNet-Santé cohort

Purpose While many cancer patients are affected by weight loss, others tend to gain weight, which may impact prognosis and risk of recurrence and of second cancer. The aim of this prospective study was to investigate weight variation between before and after cancer diagnosis and socio-demographic, economic, lifestyle and clinical factors associated with moderate-to-severe weight gain. Methods 1051 incident cases of first primary cancer were diagnosed in the NutriNet-Santé cohort between 2009 and 2015. Weight was prospectively collected every 6 months since subjects’ inclusion (i.e. an average of 2y before diagnosis). Mean weights before and after cancer diagnosis were compared with paired Students t-test. Factors associated with moderate-to-severe weight gain (≥5% of initial weight) were investigated by age and sex-adjusted logistic regression. Results Weight loss was observed in men (-3.54±4.39kg in those who lost weight, p=0.0002) and in colorectal cancer patients (-3.94±4.40kg, p=0.001). Weight gain was observed in breast and skin cancers (2.83±3.21kg, p=0.04, and 2.96±2.75kg, p=0.04 respectively). Women (OR=1.75[1.06-2.87],p=0.03), younger patients (2.44[1.51-3.70],p<0.0001), those with lower income (OR=1.30[1.01-1.72],p-trend=0.007), lower education (OR=1.32[1.03-2.70],p-trend=0.03), excess weight before diagnosis (OR=1.64[1.12-2.42],p=0.01), lower physical activity (OR=1.28[1.01-1.64],p=0.04) and those who stopped smoking (OR=4.31[1.99-9.35],p=0.005]) were more likely to gain weight. In breast cancer patients, induced menopause was associated with weight gain (OR=4.12[1.76-9.67]), but no association was detected for tumor characteristics or treatments. Conclusion This large prospective cohort provided original results on weight variation between before and after cancer diagnosis, highlighting different weight trajectories. Socio-demographic and economic factors appeared to influence the risk of weight gain, illustrating social inequalities in health.

Nutritional quality of food as represented by the FSAm-NPS nutrient profiling system underlying the Nutri-Score label and cancer risk in Europe: Results from the EPIC prospective cohort study

Background Helping consumers make healthier food choices is a key issue for the prevention of cancer and other diseases. In many countries, political authorities are considering the implementation of a simplified labelling system to reflect the nutritional quality of food products. The Nutri-Score, a five-colour nutrition label, is derived from the Nutrient Profiling System of the British Food Standards Agency (modified version) (FSAm-NPS). How the consumption of foods with high/low FSAm-NPS relates to cancer risk has been studied in national/regional cohorts but has not been characterized in diverse European populations. Methods and findings This prospective analysis included 471,495 adults from the European Prospective Investigation into Cancer and Nutrition (EPIC, 1992–2014, median follow-up: 15.3 y), among whom there were 49,794 incident cancer cases (main locations: breast, n = 12,063; prostate, n = 6,745; colon-rectum, n = 5,806). Usual food intakes were assessed with standardized country-specific diet assessment methods. The FSAm-NPS was calculated for each food/beverage using their 100-g content in energy, sugar, saturated fatty acid, sodium, fibres, proteins, and fruits/vegetables/legumes/nuts. The FSAm-NPS scores of all food items usually consumed by a participant were averaged to obtain the individual FSAm-NPS Dietary Index (DI) scores. Multi-adjusted Cox proportional hazards models were computed. A higher FSAm-NPS DI score, reflecting a lower nutritional quality of the food consumed, was associated with a higher risk of total cancer (HRQ5 versus Q1 = 1.07; 95% CI 1.03–1.10, P-trend < 0.001). Absolute cancer rates in those with high and low (quintiles 5 and 1) FSAm-NPS DI scores were 81.4 and 69.5 cases/10,000 person-years, respectively. Higher FSAm-NPS DI scores were specifically associated with higher risks of cancers of the colon-rectum, upper aerodigestive tract and stomach, lung for men, and liver and postmenopausal breast for women (all P < 0.05). The main study limitation is that it was based on an observational cohort using self-reported dietary data obtained through a single baseline food frequency questionnaire; thus, exposure misclassification and residual confounding cannot be ruled out. Conclusions In this large multinational European cohort, the consumption of food products with a higher FSAm-NPS score (lower nutritional quality) was associated with a higher risk of cancer. This supports the relevance of the FSAm-NPS as underlying nutrient profiling system for front-of-pack nutrition labels, as well as for other public health nutritional measures.

Fasting and weight-loss restrictive diet practices among 2,700 cancer survivors: results from the NutriNet-Santé cohort: Fasting and weight-loss restrictive diet practices

Nutrition is often used by cancer survivors as a lever to take charge of their own health. However, some dietary behaviors are not currently recommended for patients without medical supervision. Our study aimed at evaluating weight‐loss restrictive diets and fasting practices among cancer survivors of the NutriNet‐Santé cohort, as well as related socio‐demographic and lifestyle factors. In October 2016, 2,741 cancer survivors had completed a specific questionnaire about their practices. Fasting and non‐fasting patients (respectively dieting and non‐dieting) were compared using logistic regression models. Analyses were weighted according to the age, gender, and cancer location distribution of French cancer cases. 13.8% had already practiced weight‐loss restrictive diet as their diagnosis. They were more likely to be women, professionally active, overweight/obese, to use dietary supplements and to have breast cancer (all p < 0.05). 6.0% had already fasted, 3.5% as their diagnosis. They were more likely to be younger, with higher educational level, higher incomes, professionally active, to have a healthy weight, and to use dietary supplements (all p < 0.05). Fasting was associated with the opinion that such practice could improve cancer prognosis (p < 0.0001). Patients who received nutritional information from health care professionals were less likely to practice fasting or weight‐loss restrictive diet (0.42[0.27–0.66], p < 0.0001 and 0.49[0.38–0.64], p < 0.0001 respectively). Our study provided original results suggesting that weight‐loss restrictive diets are widely practiced by cancer survivors. Fasting was less common in our study though non negligible. Sources of nutritional information received as cancer diagnosis seemed to be a key determinant of these practices.

Association between a pro plant-based dietary score and cancer risk in the prospective NutriNet-santé cohort: Pro-animal/vegetable score and cancer risk

Diverse plant products (e.g. fruits, vegetables, legumes) are associated with decreased cancer risk at several locations while red and processed meat were found to increase cancer risk. A pro plant‐based dietary score reflecting the relative contribution of consumed plant vs animal products was developed, and was associated with lower overall mortality, type 2 diabetes and cardiovascular disease risk, among omnivorous adults. For the first time, we investigated the prospective associations between this pro plant‐based dietary score and cancer risk. This study included 42,544 men and women of the French NutriNet‐Santé prospective cohort (2009‐2016) aged ≥45 years who completed at least three 24‐hr‐dietary records during the first year of follow‐up. The risk of developing cancer was compared across sex‐specific tertiles of pro plant‐based dietary score by multivariable Cox models. In total, 1,591 first primary incident cancer cases were diagnosed during follow‐up, among which 487 breast, 243 prostate, 198 digestive and 68 lung cancers. A higher pro plant‐based dietary score was associated with decreased risks of overall (HRt3vs.t1=0.85; 95% CI 0.76, 0.97; Ptrend =0.02), digestive (HRt3vs.t1=0.68; 95% CI 0.47; 0.99; Ptrend = 0.04) and lung (HRt3vs.t1=0.47; 95% CI 0.25, 0.90; Ptrend =0.02) cancer, though no substantial associations were found for breast or prostate cancers. This large cohort study supports a beneficial role of higher intakes of plant‐based products along with lower intakes of animal products, within a balanced omnivorous diet, regarding primary cancer prevention. These results are consistent with mechanistic evidence from experimental studies.

Cancer-Specific and General Nutritional Scores and Cancer Risk: Results from the Prospective NutriNet-Santé Cohort

Several national and international authorities have proposed nutritional and lifestyle recommendations with the aim of improving health of the general population. Scores of adherence to these recommendations can be calculated at the individual level. Here, we investigated the associations between four nutritional scores and overall, breast, prostate, and colorectal cancer risk in a large prospective population-based cohort: the cancer-specific World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) score, the Alternate Healthy Eating Index 2010 (AHEI-2010), a score based on adherence to the Mediterranean diet (MEDI-LITE), and the French National Nutrition Health Program-Guideline Score (PNNS-GS). This study included 41,543 participants aged ≥40 years from the NutriNet-Santé cohort (2009-2017). A total of 1,489 overall incident cancers were diagnosed. A one-point increment of the WCRF/AICR score was significantly associated with decreased overall [12%; 95% confidence interval (CI), 8%-16%; P < 0.0001], breast (14%; 95% CI, 6%-21%; P = 0.001), and prostate (12%; 95% CI, 0%-22%; P = 0.05) cancer risks. Hazard ratio for colorectal cancer risk was 0.86 (95% CI, 0.72-1.03; P = 0.09). The PNNS-GS score was associated with reduced colorectal cancer risk (P = 0.04) and AHEI-2010 was associated with reduced overall cancer risk (P = 0.03). The WCRF/AICR score performed best. Compared with other tested scores, it included a stronger penalty for alcohol, which is a major risk factor for several cancer sites. Better adherence to nutritional recommendations, especially those designed for cancer prevention, could substantially contribute to decreased cancer incidence.Significance: This large prospective population-based cohort study suggests that following dietary recommendations such as the ones proposed by the World Cancer Research Fund/American Institute for Cancer Research could significantly contribute to cancer prevention. Cancer Res; 78(15); 4427-35. ©2018 AACR.