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Effects of vitamin D3, omega-3 fatty acids and a simple home exercise program on change in physical activity among generally healthy and active older adults: The 3-year DO-HEALTH trial

Hussein K, Kistler-Fischbacher M, Mattle M, De Godoi Rezende Costa Molino C, Tsai LT, Kressig RW, Orav EJ, Da Sliva JAP et al.

The journal of nutrition, health & aging, 2025

Abstract

OBJECTIVES: Physical function and physical activity (PA) are key drivers of health and autonomy at older age. We examined the effects of supplemental vitamin D3, supplemental marine omega-3 fatty acids (omega-3s), and a simple home exercise program (SHEP), alone or in combination, on change in physical function and PA among generally healthy older adults.

DESIGN: Multi-center, 2 × 2 × 2 factorial design, randomized controlled trial, follow-up of three years METHODS: Self-reported PA and physical function were pre-defined outcomes of the DO-HEALTH trial, which included older adults (≥70 years) free of major comorbidities. The interventions were vitamin D3 (2000 IU/d), marine omega-3s (1 g/d), and a SHEP (3 × 30 min/wk), applied alone or in combination in eight treatment arms. The outcomes were change in PA (self-reported total PA, metabolic equivalent [MET] h/wk) and physical function (five times sit-to-stand test, hand grip strength, gait speed) from baseline to 12, 24 and 36 months. Mixed effect models were used and adjusted for age, sex, BMI, prior fall, time and baseline level of the outcome.

RESULTS: All 2157 DO-HEALTH participants (mean age 75 years; 83% physically active; 59% vitamin D3 replete) were included. Baseline PA was 75 MET h/wk. Participants receiving omega-3s versus no omega-3s and randomized to SHEP versus control exercise did not differ in PA change over 3 years. However, participants receiving vitamin D3 compared to those receiving no vitamin D3…

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Evidence Hub reads this as a randomized trial, done in people. Its evidence level is 2 of 5 (High · randomized trial). Randomized trials of a reasonable size are the strongest single-study design.

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