Very few studies have investigated the determinants of serum vitamin D levels using a set of variables that include simultaneously sun exposure, phototype, dietary intake, sociodemographics, anthropometric, lifestyle data, and genetic polymorphisms. Our objective was to investigate the associations between all these parameters and vitamin D status in a large sample of French adults. This cross-sectional survey was based on 1,828 middle-aged Caucasian adults from the SU.VI.MAX (SUpplémentation en VItamines et Minéraux AntioXydants) study. Plasma 25-hydroxyvitamin D (25OHD) concentration was lower among women (P<0.0001), older subjects (P=0.04), obese/underweight (P<0.0001), those living at higher latitudes (P<0.0001), those whose blood draw occurred in early spring (P<0.0001), less physically active (P<0.0001), with low sun exposure (P<0.0001), and with no-to-low alcohol intake (P=0.0001). Mutant GC rs4588 and rs7041 single nucleotide polymorphisms were associated with lower and higher 25OHD concentrations, respectively (P<0.0001). Dietary intake was not a major determinant of vitamin D status (P=0.7). This study provides an overall picture of determinants of vitamin D status. Several modifiable factors were identified, such as daily-life moderate sun exposure, physical activity, and normal-weight maintenance, which should be targeted by public health policies in order to improve vitamin D status in the general population, while avoiding active/intensive sun exposure, in line with recommendations for skin cancer prevention.
1 November 2015 in Nutrition, Metabolism and Cardiovascular Diseases
Background: Cardiovascular diseases (CVD) are the leading cause of death in the world, and diet plays a major role in CVD incidence, especially through lipid oxidation mechanisms. This, in turn, leads to tissue inflammation and formation of atheromatous plaques. Methods and Results: Our objective was to evaluate the association between the inflammatory potential of the diet and the incidence of overall CVD or its subclasses. We included 7743 participants from the Supplémentation en Vitamines et Minéraux AntioXydants (SU.VI.MAX) cohort. All cardiovascular events were recorded using self‐reported information or clinical visits, and were validated. The dietary inflammatory index (DII) was computed using repeated 24‐hour dietary records (mean=9.5±3.4 records/subject). Hazard ratio and 95% CI for outcomes (CVD and subclasses) were estimated across sex‐specific quartiles of the DII using Cox proportional hazard models. A total of 292 cardiovascular events were recorded and validated during an average of 11.4 years of follow‐up: 93 myocardial infarctions, 58 strokes, 128 angina pectoris and revascularization interventions, and 13 sudden deaths. When considering CVD subclasses, a diet with pro‐inflammatory properties, as expressed by higher DII scores, was significantly associated with a higher risk of myocardial infarction (hazard ratio Quartile 4 versus Quartile 1 =2.24, 95% CI: 1.08–4.67). No significant association was observed between the DII score and stroke or both angina pectoris and revascularization intervention. Conclusions: A pro‐inflammatory diet, as measured by a higher DII score, was prospectively associated with a higher risk of myocardial infarction. Promotion of a diet exhibiting anti‐inflammatory properties may help prevent myocardial infarctions.
A lower BMI has been reported among consumers of organic foods, but this relationship has never been examined in a prospective design study. Our aim was to prospectively investigate the association between frequency of organic food consumption and weight change. We analysed data from 62 224 participants of the NutriNet-Santé cohort (78 % women, mean age=45 years) with information on consumption frequency of organic foods, dietary intake and repeated anthropometric data. For sixteen products, participants reported their consumption frequency of labelled organic foods (never, occasionally, most of the time). An organic score (OS) with a maximum of thirty-two points was computed. The associations of the OS (modeled as quartiles (Q)) with change in BMI during follow-up (on average 3·1 years) and with the risk of overweight and obesity were estimated by ANCOVA and multivariable logistic regression. A lower BMI increase was observed across quartiles of the OS (mean difference Q4 v. Q1=−0·16 (95 % CI −0·32, −0·01). An increase in the OS was associated with a lower risk of overweight and obesity (among non-overweight and non-obese participants at inclusion): OR for Q4 v. Q1 were 0·77 (95 % CI 0·68, 0·86) and 0·69 (95 % CI 0·58, 0·82), respectively. Concerning obesity risk, the association was stronger among participants with higher adherence to nutritional guidelines. This study supports a strong protective role of consumption frequency of organic foods with regard to the risk of overweight and obesity that depends on overall dietary quality. Upon confirmation, these results may contribute to fine-tune nutritional guidelines by accounting for farming practices in food production.