Adherence to French Dietary Guidelines Is Associated with a Reduced Risk of All-Cause, Cardiovascular Diseases and All, Breast and Lung Cancer Mortality in the E3N COHORT ^†

Abstract

Background and objectives: Diet is a modifiable risk factor of non-communicable diseases. The French dietary guidelines, updated in 2017, provide recommendations for a healthier diet. We aimed to study the association between adherence to these dietary guidelines and mortality in the E3N (Etude Epidémiologique auprès de femmes de l’Education Nationale) French cohort. Methods: We studied 72,585 women included in the E3N prospective cohort, which completed a food frequency questionnaire in 1993. Adherence to French dietary guidelines was estimated using the simplified “Programme National Nutrition Santé—guidelines score 2” (sPNNS-GS2, range: −20.4 to 12.6). We estimated the association between sPNNS-GS2 and all-cause or cause-specific mortality using Cox proportional hazard models, adjusted for age (as time-scale), BMI, physical activity, birth generation, education level, smoking status, menopausal status and recent menopausal hormone therapy use, and total energy intake. Results: During follow-up (1993–2014), we identified 6441 deaths. The mean sPNNS-GS2 was 3.8 (SD 3.0). In the fully adjusted model, we found a non-linear inverse association, with a plateau from the third quartile, between sPNNS-GS2 and all-cause (HRQ4 vs. Q1 [95%CI]: 0.79 [0.73; 0.86]), all cancers (HRQ4 vs. Q1 [95%CI]: 0.79 [0.70; 0.89]) and breast cancer (HRQ4 vs. Q1 [95%CI]: 0.73 [0.58; 0.91]) mortality. We also highlighted a non-linear U-shaped association with lung cancer mortality (HRQ3 vs. Q1 [95%CI]: 0.62 [0.45; 0.87] and HRQ4 vs. Q1 [95%CI]: 0.73 [0.52; 1.02]) and a linear inverse association with cardiovascular disease mortality (HRoneSTD [95%CI]: 0.86 [0.76; 0.97]). We observed no association with colorectal cancer mortality (HRoneSTD [95%CI]: 0.86 [0.70; 1.04]). Discussion: This study on a large prospective cohort following more than 70,000 women for over 20 years suggests that a higher adherence to the French dietary guidelines is associated with a reduced risk of mortality from all-cause cardiovascular diseases, all cancers, breast cancer and lung cancer. These results enable us to confirm the French nutritional recommendations. Finally, the reduced risk observed for various mortality outcomes is an important public health message.