Association of enhanced protein intake with handgrip strength in postmenopausal women: a systematic review and meta-analysis.

IMPORTANCE: Low handgrip strength (HGS) is a highly prevalent condition in postmenopausal women, although there is no clear evidence about the convenience and benefit of enhanced protein intake (EPI). OBJECTIVE: This systematic review and meta-analysis evaluate the association between EPI and HGS in postmenopausal women. EVIDENCE REVIEW: The meta-analysis protocol was registered in the PROSPERO database (CRD420261299335). We adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A comprehensive literature search was conducted up to February 2026 across four databases (PubMed, Web of Science, Scopus, and LILACS) for studies comparing the effect of EPI with mild protein intake on the HGS in postmenopausal women. The quality of the included studies was assessed using the Newcastle-Ottawa Scale. Statistical analyses were performed with the RevMan 5.4 software. Results are reported as standardized mean difference (SMD) and the 95% CI. FINDINGS: Seven studies with low or moderate risk of bias, including 8,922 postmenopausal women, showed that EPI was significantly associated with HGS (SMD: 0.15, 95% CI: 0.10 to 0.20; Z = 5.54, P < 0.0001; I2 = 6%, τ2 = 0.00) compared with the control group under low protein intake. There was a lower body mass index in women under EPI compared with the control group (SMD: -0.43, 95% CI: -0.68 to -0.18; Z = 3.35, P < 0.0001; I2 = 90%, τ2 = 0.04), and there was no significant age difference (SMD: -0.17, 95% CI: -0.36 to 0.02; I2 = 83%, τ2 = 0.08). The HGS sensitivity analysis for protein intake and HGS indicates that the statistical heterogeneity was low, ranging I2 from 0% to 22%. CONCLUSION AND RELEVANCE: Postmenopausal women with EPI have significantly higher HGS and lower body mass index compared with those with lower protein intakes.