Many older adults don't receive sufficient amounts of vitamin D, omega-3 fatty acids, and exercise, all of which may prevent age-related chronic diseases. Researchers conducted a multicenter, randomized, double-blind, placebo-controlled trial to determine whether vitamin D supplementation, omega-3 supplementation, or a strength training exercise program-alone or in combination-would improve six health outcomes among relatively healthy adults age 70 or older.
Community-dwelling adults in this age range were recruited for the study if they had no major health events in the previous five years, sufficient mobility, and good cognitive function. Participants (mean age, 74.9 years) were randomized to one of eight treatment groups: vitamin D3 (2,000 IU/day), omega-3 fatty acids (1 g/day), and a strength training exercise program; vitamin D3 and omega-3 fatty acids; vitamin D3 and exercise; vitamin D3 alone; omega-3 fatty acids and exercise; omega-3 fatty acids alone; exercise alone; and placebo. They were followed for a median of 2.99 years. Adherence to study interventions was high, and mortality and loss to follow-up were minimal.
None of the interventions, either alone or together, resulted in significant improvement in any of the six primary end points: systolic blood pressure; diastolic blood pressure; nonvertebral fractures; lower extremity function, as measured by the Short Physical Performance Battery; cognitive function, as measured by the Montreal Cognitive Assessment; and incidence of infections.
The authors point out that most study participants had already been engaging in moderate to high levels of physical activity. Their physical performance and cognitive function were good at baseline, which may have left little room for further benefit from the interventions.