Metabolic response to epigallocatechin-3-gallate in relapsing-remitting multiple sclerosis: a randomized clinical trial.

Randomized, double-blind, placebo-controlled, crossover trial in adults with relapsing-remitting multiple sclerosis. Eighteen participants completed the study (8 men, 10 women), all Caucasian, aged 20 to 60 years, with mild disability and stable glatiramer acetate therapy; eligibility also required BMI 18.5 to 30.0 kg/m^2 and EDSS ≤ 4.5.

Oral epigallocatechin-3-gallate (EGCG) 600 mg/day was given as 150 mg capsules twice daily, 1 hour before breakfast and dinner, for 12 weeks per treatment period in a randomized crossover comparison with placebo. Participants completed both EGCG and placebo periods, separated by a 4-week washout.

EGCG produced sex-specific metabolic effects rather than a uniform benefit. Compared with placebo, resting postprandial fat oxidation was 40% higher in men and 21% lower in women, and during moderate exercise postprandial energy expenditure was lower after EGCG, indicating greater working efficiency. Muscle work efficiency increased from 21% with placebo to 27% with EGCG in men and from 20% to 25% in women; fasting adipose tissue lactate was lower with EGCG in men but not women, and triglycerides were significantly lower in men (P = 0.005). Overall, 12 weeks of EGCG modulated energy metabolism in a sex-specific manner, with greater improvement in men than in women.

The study was very small and single-center, which limits precision and generalizability. The crossover periods were short, and the sex-specific findings may be underpowered. All participants were Caucasian patients with relapsing-remitting multiple sclerosis on stable glatiramer acetate, so applicability to broader populations is limited; adverse-event reporting was not stated.