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Background Nutritional factors are essential for the functioning of the immune system and could therefore play a role in COVID-19 but evidence is needed. Our objective was to study the associations between diet and the risk of SARS-CoV-2 infection in a large population-based sample. Methods Our analyses were conducted in the French prospective NutriNet-Santé cohort study (2009–2020). Seroprevalence of anti-SARS-CoV-2 antibodies was assessed by ELISA on dried blood spots. Dietary intakes were derived from repeated 24 h dietary records (at least 6) in the two years preceding the start of the COVID-19 pandemic in France (February 2020). Multi-adjusted logistic regression models were computed. Results A total of 7766 adults (70.3% women, mean age: 60.3 years) were included, among which 311 were positive for anti-SARS-CoV-2 antibodies. Dietary intakes of vitamin C (OR for 1 SD=0.86 (0.75–0.98), P=0.02), vitamin B9 (OR=0.84 (0.72–0.98), P=0.02), vitamin K (OR=0.86 (0.74–0.99), P=0.04), fibers (OR=0.84 (0.72–0.98), P=0.02), and fruit and vegetables (OR=0.85 (0.74–0.97), P=0.02) were associated to a decreased probability of SARS-CoV-2 infection while dietary intakes of calcium (OR=1.16 (1.01–1.35), P=0.04) and dairy products (OR=1.19 (1.06–1.33), P=0.002) associated to increased odds. No association was detected with other food groups or nutrients or with the overall diet quality. Conclusions Higher dietary intakes of fruit and vegetables and, consistently, of vitamin C, folate, vitamin K and fibers were associated with a lower susceptibility to SARS-CoV-2 infection. Beyond its established role in the prevention of non-communicable diseases, diet could therefore also contribute to prevent some infectious diseases such as COVID-19.

Context and objectiveWhen considering the health-related impact of foods, nutrient profile (content in salt, sugar, fibre, etc.) and (ultra-)processing are two complementary dimensions. The Nutri-Score, a summary graded front-of-pack label, already used in seven European countries, informs on the nutrient profile dimension, i.e. the one with the strongest evidence. Recently, mounting evidence linked ultra-processed food consumption to various adverse health outcomes, independently of their nutrient profile. To inform consumers about each of these two health-related dimensions of food (i.e., nutrient profile and ultra-processing), we aimed to test, in a randomised controlled trial, if a graphically modified version “Nutri-Score 2.0”, including a black “ultra-processed” banner, would improve the capacity of consumers to rank products according to their nutrient profile but also to detect those ultra-processed, compared to a no-label situation.MethodsA total of 21,159 participants included in the NutriNet-Santé web-cohort were randomly assigned to a control arm (no front-of-pack label) or an experimental arm (Nutri-Score 2.0), and were presented an online interactive questionnaire with 3 sets of food products (8 cookies, 7 breakfast cereals, and 7 ready-to-eat meals) to rank according to their nutrient profile, and to identify ultra-processed foods. The primary outcome was the objective understanding of nutrient profile and ultra-processing, represented by a score of correct answers. Secondary outcomes were purchasing intentions and the healthiest-perceived product. Multinomial logistic regressions were performed.ResultsThe Nutri-Score 2.0 increased significantly the objective understanding of both the nutrient profile dimension of food products from 0.9% to 24.2% (OR = 29.0 (23.4 – 35.9), pConclusionThis randomised controlled trial demonstrates the interest of a front-of-pack label combining the Nutri-Score (informing on the nutrient profile dimension) with an additional graphic mention indicating when the food is ultra-processed, compared to a no-label situation. Our results show that participants were able to independently identify and understand these two complementary dimensions of foods.Trial registration numberNCT05610930

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Background Obesity has been identified as an important risk factor for COVID-19 severity. Besides, several reports also suggested that obesity (or a higher BMI) may also be associated with a higher susceptibility to SARS-CoV-2 infection although this remains unclear. Going beyond BMI, our objective was to study several anthropometric characteristics in relation to the seroprevalence of SARS-CoV-2 infection in a large population-based sample. Methods 21,376 participants from the French NutriNet-Santé cohort study were included in the main analyses. An ELISA assay was used to detect anti-SARS-CoV-2 antibodies: 1027 participants were positive and 20,349, negative. Associations between a wide range of anthropometric characteristics (body mass index but also waist and hip circumference and body composition) and the seroprevalence of anti-SARS-CoV-2 antibodies were investigated using multi-adjusted logistic regressions. Results A positive yet unclear association was observed between BMI and SARS-CoV-2 seroprevalence in women (positive linear trend (P = 0.07) that was significant using restricted cubic splines (P = 0.04), but no association with standard categories of BMI). No association was observed in men. Waist circumference (P = 0.04) and waist-to-hip ratio (P = 0.01) associated with a higher seroprevalence in women while opposite trends were observed in men (P = 0.08 and 0.03 respectively). Body, trunk and visceral fat (all P < 0.05), but not lean or muscle mass, associated with higher seroprevalence, especially in women. Conclusions Our results highlight a higher susceptibility to SARS-CoV-2 infection in women with higher body fat, suggesting that central adiposity may be an important factor to consider for risk stratification in the population. Key messages A higher seroprevalence of SARS-CoV-2 infection was observed in women with a higher body fat, but not in men. Central adiposity may be a risk factor for SARS-CoV-2 infection and not only for COVID-19 severity.

Background: Breast cancer remains the leading cancer in women. In 2018, following its summary report, the World Cancer Research Fund (WCRF) issued its recommendations for cancer prevention based on the nutritional risk factors with a sufficient level of evidence, several of which being related to breast cancer. Our objective was to study whether adherence to these new recommendations was actually associated with reduced risk of breast cancer. Methods: A total of 62,546 women from the NutriNet-Santé population-based cohort study (2009-2019) were included in our analyses. Adherence to the 2018 WCRF recommendations was assessed using the operationalized score on a 7-point scale, proposed by Shams-White et al (Nutrients 2019), including: weight, physical activity, fruit and vegetables, dietary fibers, ultra-processed foods, red and processed meat, sugary drinks and alcohol. Usual dietary intakes were assessed using repeated 24h-dietary records and physical activity level using the IPAQ questionnaire. Cox proportional hazard models were computed with adjustment for the following potential confounders: educational level, height, smoking status, number of 24h dietary records, family history of cancer, number of biological children, age at menarche, age at parity, menopausal status, use of oral contraception or hormonal treatment for menopause. Results: During a median follow-up of 7.3 years, 745 women were diagnosed with a first incident breast cancer. The median WCRF 2018 adherence score was 3.75 (IQR: 3.25-4.50). An increase of 1-point increment in the score was associated with a decreased risk of breast cancer (HR=0.92; 95%CI 0.85-1.00; P=0.05), and especially of breast cancer post-menopause (n=456 cases, HR=0.88; 0.79-0.98; P=0.02). No association was observed for breast cancer pre-menopause (n=289, HR=0.99; 0.87-1.12; P=0.8). Sugary drink, alcohol and weight components of the score particularly contributed to the observed association. Conclusions: Our results suggest that a higher adherence to the WCRF 2018 recommendations for cancer prevention is associated to a decreased risk of breast cancer. Considering that the WCRF cancer recommendations are consistent with overall food-based dietary guidelines, such recommendations should be promoted to the general public and transposed as public health actions to contribute to decrease the burden of cancer. Citation Format: Mélanie Deschasaux, Laurent Bourhis, Laurent Zelek, Eloi Chazelas, Charlotte Debras, Serge Hercberg, Paule Latino-Martel, Chantal Julia, Emmanuelle Kesse-Guyot, Bernard Srour, Mathilde Touvier. Adherence to the new WCRF cancer prevention recommendations associates with a decreased breast cancer risk [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD11-01.

Augmentation index (AIx), a marker of the number of aortic wave reflections (AWRs), is influenced not only by the magnitude of incident and reflected pressure waves but also by the time of return. A new triangulation method has been developed, enabling us to better quantify AWRs and to determine their sex differences, which may relate to body size or pulse pressure (PP) amplification, measured from the brachial PP-to-carotid PP (B/C) ratio. With the use of pulse wave analysis, AWRs were evaluated in 51 women and 72 men treated for hypertension and studied in relationship to age, blood pressure, and pulse wave velocity. When women were compared with men, AIx (expressed in %PP and adjusted to heart rate) was significantly higher, together with a significant decrease of the B/C ratio and an increase of the reflection magnitude and of the amplitude (but not the timing) of the backward pressure wave. The significance of the amplitude difference between men and women was enhanced after an adjustment to heart rate or pulse wave velocity but was abolished after an adjustment to body height or the B/C ratio. In the overall population, AIx and the reflection magnitude index were positively ( r2 = 0.39) and independently associated, after excluding confounding factors such as drug treatment. In conclusion, when compared with men, women treated for hypertension have increased AIx, related to the increased amplitude, and not timing, of backward pressure waves. This finding relates to sex differences in body size and mostly brachial-carotid PP amplification, a parameter highly related to the sex difference of cardiovascular risk.