Association between the digestion-resistant bioactive peptide content in dairy products and the risk of sarcopenia in Iranian elderly: a case-control study.

BACKGROUND

Sarcopenia is a generalized and progressive loss of skeletal muscle mass and function, which is associated with various adverse health outcomes, such as fractures, impaired mobility, and increased mortality. Bioactive peptides (BPs) are absorbable protein fragments that remain bioaccessible after digestion. In the present study, we investigated whether the intake of BPs derived from dairy products could reduce the risk of sarcopenia by analyzing the dietary habits of elderly individuals with sarcopenia.

METHODS

This case-control study used data collected from a population-based cross-sectional study conducted at healthcare centers in Shiraz, Iran. A total of 80 individuals diagnosed with sarcopenia and 80 control subjects without sarcopenia were selected. Sarcopenia was defined according to the diagnostic criteria established by the Asian Working Group for Sarcopenia. Dietary intake over the previous year was assessed using a semi-quantitative food frequency questionnaire consisting of 168 items. The amount of digestion-resistant BPs in dairy products was estimated by multiplying the grams of dairy consumed by the peptide content present in these products. The association between the intake of digestion-resistant BPs from dairy products and the risk of sarcopenia was evaluated using logistic regression analysis.

RESULTS

In the unadjusted analysis, participants with higher total peptide consumption had markedly reduced odds of sarcopenia compared with those in the lower-intake reference group (odds ratio [OR ]= 0.163, 95% confidence interval [CI]: 0.082-0.323, P < 0.001). After adjusting for potential confounders, the inverse association between total peptide intake and the odds of sarcopenia remained statistically significant. Individuals with greater total peptide intake showed substantially lower odds of sarcopenia than those in the low-intake reference group (OR = 0.336, 95% CI: 0.149-0.897, P = 0.028).

CONCLUSIONS

In summary, our findings suggest that BPs derived from dairy products are inversely associated with the risk of sarcopenia. Given the cross-sectional and retrospective design, causality cannot be established, and further prospective or interventional studies are needed to confirm these associations.