Associations between dietary diversity and self-rated health in a transverse study of four local food systems (French Guiana, Guadeloupe, Portugal and Senegal).

Background: The nutrition transition is linked to the double-burden of malnutrition worldwide, and its impact on the quality of life is considerable. The dietary diversity score and self-rated health are two proxies that have been used to assess, for the former, nutrient adequacy and overall diet quality, and for the latter, health from a sociological, epidemiological and economical lens. The general aim of this study was to evaluate the relation between food and subjective health, and to test the hypothesis that greater dietary diversity is positively associated with a better perception of health.

Methods: A transverse comparison of foods consumed in four highly contrasted local socio-ecosystems (i.e., two French oversea territories: French Guiana, Guadeloupe, Portugal and Senegal) was conducted using 24-hour dietary recalls. Dietary diversity was calculated using 18 food groups based on classifications provided by WHO and FAO. Binary logistic regressions were used to assess the relationship between dietary diversity scores and answers to the question assessing self-rated health.

Results: Overall, 465 individuals, 18 years and older, from Senegal, Guiana, Guadeloupe and Portugal were interviewed using a 24-hour dietary recall. Participants were selected via a combination of non-probability sampling methods. The mean dietary diversity score for all regions combined was 9.22. Over one-third of participants reported their health as 'good' (39.8%), whereas 'bad' and 'excellent' health were the least reported, at 6.45% and 9.03%, respectively. Multiple binary logistic regression notably found that dietary diversity score (OR = 0.88, 95% CI [0.79, 0.99], p = 0.010) and at-home meal preparation, specifically with the reference category 'all the time' compared to 'never' (OR = 3.31, 95% CI [1.55, 7.07], p = 0.002) were statistically significant predictors of self-rated health (i.e., declaring overall bad health).

Conclusions: This study demonstrates a positive association between dietary diversity and self-rated health across distinct cultural contexts. The findings reinforce the importance of diverse diets for subjective well-being, regardless of differences in food systems. Public health messaging should continue to promote dietary diversity and home-cooked meals as effective strategies for improving health. Self-rated health could serve as a useful tool for quickly assessing the outcomes of nutrition therapy.