Abstract
OBJECTIVES: Cohort studies with sufficient follow-up that include an assessment of overall diet quality are necessary to determine the prospective relationship between consumption of ultra-processed foods (UPFs) and muscle strength. DESIGN: Prospective cohort study. SETTING AND PARTICIPANTS: We included 13,570 participants from the Singapore Chinese Health Study who were recruited at a mean age of 53 years from 1993 to 1998, and re-visited at follow-up 3 when they were at a mean age of 74 years from 2014 to 2017, after a median follow-up of 21.2 years. MEASUREMENTS: At baseline, UPFs were defined according to the Nova classification using dietary information collected via a validated 165-item food-frequency questionnaire. During the third follow-up visits, handgrip strength was measured using a digital grip strength dynamometer. Muscle weakness was defined as the lowest sex-specific quintile of handgrip strength. RESULTS: Compared to participants in the lowest quintile of UPF consumption, those in the highest quintile of UPF consumption showed a reduction of 0.411 kg [95% confidence interval (CI), 0.148, 0.674] in absolute handgrip strength, a reduction of 0.229 kg/m (95% CI, 0.071, 0.387) in handgrip strength by height, and an OR of 1.32 (95% CI, 1.15, 1.53) for muscle weakness. These associations remained significant after adjusting for overall diet quality. CONCLUSION: Higher UPF consumption in midlife is linked to lower handgrip strength in later life, independent of overall diet quality.