Total physical activity, plant-based diet and neurodegenerative diseases: A prospective cohort study of the UK biobank

Neurodegenerative diseases (NDDs) result from a complex interplay of genetic, environmental and aging factors. A balanced diet and adequate physical activity (PA) are recognized as pivotal components among modifiable environmental factors. The independent impact on NDD incidence has been previously debated. This investigation seeks to delineate the association between PA and NDDs across various levels of adherence to a plant-based diet.

In this study, a cohort of 368,934 participants from the UK Biobank was analyzed. Total physical activity (TPA) levels and healthful plant-based diet index (hPDI) were calculated and categorized. A multiple adjusted Cox model was utilized to evaluate the influence of TPA and hPDI on common NDDs, respectively.

Finally, 4602 identified cases diagnosed as Alzheimer's disease (AD), Parkinson's disease (PD) or amyotrophic lateral sclerosis (ALS). We found that higher TPA was significantly associated with a reduced risk of developing AD (Q3: HR 0.87; Q4: HR 0.78) and PD (Q3: HR 0.86; Q4: HR 0.81). The protective effect was further accentuated with adherence to a plant-based diet. However, these connections were not observed in the analysis of ALS regardless of dietary patterns.

Our findings underscore a significant association between higher TPA and reduced risks of AD and PD, with an enhanced effect observed in conjunction with a plant-based diet. This study contributes to addressing the knowledge gap regarding the combined impact of TPA and a plant-based diet on NDDs occurrence, providing insights into potential underlying mechanisms.