Background: Age-related declines in physical function may be exacerbated by poor nutrition. Nuts are energy and nutrient dense and have been associated with health benefits such as preventing cardiovascular and coronary heart diseases, type 2 diabetes, and metabolic syndrome. There is emerging evidence from observational studies that nut intake is associated with better physical function. However, data on the effects of nut consumption on physical function from randomised controlled trials is needed.
Aim: To investigate the effects of consuming 43g/day of peanut butter for 6 months on the physical function of older adults.
Methods: This is a 6-month randomised controlled, parallel-arm trial. One-hundred and twenty community-dwelling older adults who are aged ≥65 years, at risk of falling, have a BMI between 18-35 kg/m2, have no nut allergies, are low nut consumers, and are generally healthy or with metabolic disease managed through lifestyle or common medications (excluding insulin) will be recruited and randomly assigned to either a peanut butter group (43g/day, equivalent to 1.5 servings of nuts; n=60) or a control group (n=60) for 6 months. The primary outcome will be physical performance measured by 4-meter usual gait speed test. Secondary outcomes will include the timed-up-and-go test, four-square step test, standing balance test, 5x sit-to-stand test, appendicular lean mass, upper and lower extremity muscle strength, falls efficacy and late life function and disability.
Discussion: This study will generate new knowledge on whether peanut butter is a simple and effective strategy to improve the physical function of community-dwelling older adults.
Trial registration: The trial is registered with the Australian New Zealand Clinical Trials Registry (ANZCTR): 12622001291774.
Funding: This project is funded by the Peanut Institute