Research Abstracts
Effects of walnut consumption for 2 years on older adults’ bone health in the Walnuts and Healthy Aging (WAHA) trial.
Oliver-Pons, C., A. Sala-Vila, M. Cofán, M. Serra-Mir, I. Roth, C. Valls-Pedret, M. Domènech, E. Ortega, S. Rajaram, J. Sabaté, E. Ros, G. Chiva-Blanch, 2024. Effects of walnut consumption for 2 years on older adults’ bone health in the Walnuts and Healthy Aging (WAHA) trial. J Am Geriatr Soc. 72(8):2471-2482. https://doi.org/10.1111/jgs.19007
Background: Nutritional strategies to maintain bone health in aging individuals are of great interest. Given the beneficial nutrient composition of walnuts, rich in alpha-linolenic (the vegetable n-3 fatty acid) and polyphenols, their regular consumption might be a dietary option to reduce age-related bone loss. We determined whether daily walnut consumption improves bone mineral density (BMD) and circulating biomarkers of bone turnover. Methods: The Walnuts and Healthy Aging study (WAHA) is a two-center, parallel, randomized controlled trial evaluating the effect of a diet enriched with walnuts at ≈15% energy compared with a control diet for 2 years on age-related health outcomes in healthy men and women aged 63–79 years. Changes in BMD were a prespecified secondary outcome only at the Barcelona node of the trial, where 352 participants were randomized. Retention rate was 92.6%. Primary endpoints were 2-year changes in BMD at the spine and the nondominant femoral neck, determined by dual-energy X-ray absorptiometry (DXA). Secondary endpoints were 2-year changes in bone turnover biomarkers (adrenocorticotropic hormone, Dickkopf WNT signaling pathway inhibitor-1, osteoprotegerin, osteocalcin, osteopontin, sclerostin, parathyroid hormone, and fibroblast growth factor-23), which were quantified in 211 randomly selected participants. Results: The walnut diet versus the control diet had no effect on 2-year changes in BMD at the spine (0.15% vs. 0.35%, p = 0.632) and femoral neck (−0.90% vs. −0.70%, p = 0.653), or on bone turnover biomarkers. Results were similar in participants treated or not with bone resorption inhibitors or those with or without osteoporosis/osteopenia at inclusion. Conclusions: Compared with the usual diet, a diet enriched with walnuts at 15% of energy for 2 years failed to improve BMD or circulating markers of bone metabolism in healthy older people.