Antioxidant-rich foods, antioxidant supplements, and sarcopenia in old-young adults ≥55 years old: A systematic review and meta-analysis of observational studies and randomized controlled trials.

Systematic review of observational studies (n=19; cross-sectional and cohort) and randomized controlled trials (n=9). Participants were adults around 55–60 years old (both genders; some studies included only women or only men) from Europe, Asia, Africa, and the Americas; follow-up in observational cohorts ranged 3–7.2 years; RCT durations ranged from 12 weeks to 24 weeks. Risk of bias assessed with RoB2 for RCTs and a 14-question tool for observational studies. Analyses conducted with Review Manager (RevMan 5.4).

Resveratrol 500 mg/day with resistance training; 12 weeks. Vitamin E 900 mg/day for 6 months. Tea catechins 540 mg/day for 3 months. Magnesium oxide 900 mg/day for 12 weeks. Whey protein + vitamin D + vitamin E (218 mg/day vitamin E) for 6 months. Vitamin C 1000 mg/day + vitamin E 400 IU/day with resistance training; 6 months. Antioxidant-rich foods/diet: five portions/day of fruits and vegetables for 16 weeks. Mediterranean-type diet: ~600 g/day of fruits/vegetables with olive oil, nuts, fish; 24 weeks. Increased fruit/vegetable consumption to five portions daily with exercise; duration varies across trials.

Observationally, higher intake of antioxidant-rich foods or patterns (A-RF) is associated with better sarcopenia outcomes (muscle mass, strength, and physical function). In RCTs, regimens including magnesium supplementation (900 mg/day), vitamin E with vitamin D and protein, and increased fruit/vegetable consumption (to 5 servings/day) significantly improved performance measures such as handgrip strength and time to complete five chair stands (about 1.0 kg handgrip increase; ~1.1 s faster on five stands). Tea catechins also improved handgrip strength. Overall, antioxidant-rich foods or antioxidant supplementation could be beneficial for sarcopenia, with the most promising interventions being vitamin E plus vitamin D and protein, magnesium, tea catechins, and higher fruit/vegetable intake. More robust trials are needed to isolate effects from lifestyle factors and to quantify clinical impact on muscle mass.

Heterogeneity in antioxidants, doses, durations, and sarcopenia outcome measures; observational studies cannot establish causality; several RCTs had risk of bias and some included concurrent exercise or overall diet confounding attribution to antioxidants alone; mixed interventions and multiple countries limit generalizability; limited data for certain outcomes (e.g., muscle mass) prevented comprehensive meta-analysis across all domains.