Association between a plant-based diet and the risk of sarcopenia among older adults: a case-control study

Limited studies have shown a negative correlation between healthy plant-based diets and sarcopenia compared to unhealthy and more limited plant-based diets. Therefore, we aimed to evaluate the association between the plant-based diet index (PDI) and the odds of sarcopenia among the elderly. In this case-control study, 80 people over 65 years old with sarcopenia and 80 people without sarcopenia participated. Based on the Asian Working Group for Sarcopenia guidelines, sarcopenia was diagnosed. Additionally, a 168-item semi-quantitative food frequency questionnaire was applied to evaluate the participants’ dietary intake. According to the PDI method, food items were classified into 18 food groups to calculate PDI, healthy PDI (hPDI), and unhealthy PDI (uPDI). Moreover, multivariable logistic regression models were considered to evaluate the association between PDIs and the odds of sarcopenia. After adjusting for age, body mass index (BMI), physical activity, education level, and income in the second model, a significant positive association was observed between higher adherence to the uPDI and sarcopenia; participants in the highest tertile of uPDI had increased odds of sarcopenia compared to those in the lowest tertile (odds ratio (OR) = 3.689, 95% confidence interval (CI): 1.284–10.593, P = 0.015). In contrast, in the fully adjusted model (adjusted for age, BMI, physical activity, energy intake, protein intake, education level, and income), higher adherence to the overall PDI was associated with reduced odds of sarcopenia; participants in the second (OR = 0.128, 95% CI: 0.030–0.556, P = 0.006) and highest tertile (OR = 0.131, 95% CI: 0.024–0.718, P = 0.019) of PDI showed a lower risk compared with those in the lowest tertile. The findings of the present study showed a negative association between PDI and the odds of sarcopenia. Further studies are recommended to confirm the current results.