Plant-based Diet and Adiposity Over Time in a Middle-aged and Elderly Population

Background: We aimed to explore whether adhering to a more plant-based diet, beyond strict vegan or vegetarian diets, may help prevent adiposity in a middle-aged and elderly population. Methods: We included 9,633 participants from the Rotterdam Study, a prospective cohort in the Netherlands. Dietary data were collected using food-frequency questionnaires at baseline of three subcohorts of the Rotterdam Study (1989–1993, 2000–2001, 2006–2008). We created a plant-based diet index by giving plant-based foods positive scores and animal-based foods reverse scores. A higher score on the index reflected an overall more plant-based and less animal-based diet. Data on anthropometrics and body composition (using dual energy X-ray absorptiometry) were collected every 3–5 years from 1989 to 2016. We used multivariable linear mixed models to analyze the associations. Results: In the 9,633 participants, baseline plant-based diet score ranged from 21.0 to 73.0 with a mean ± SD of 49.0 ± 7.0. In multivariable-adjusted analyses, higher adherence to a plant-based diet was associated with lower BMI, waist circumference, fat mass index, and body fat percentage across a median follow-up period of 7.1 years (per 10 points higher score, BMI: β = −0.70 kg/m 2 [95% CI = −0.81, −0.59]; waist circumference: −2.0 cm [−2.3, −1.7]; fat mass index: −0.66 kg/m 2 [−0.80, −0.52]; body fat percentage: −1.1 points [−1.3, −0.84]). Conclusions: In this population-based cohort of middle-aged and elderly participants, a higher adherence to a more plant-based, less animal-based diet was associated with less adiposity over time, irrespective of general healthfulness of the specific plant- and animal-based foods.