Pharmacokinetics and safety of green tea polyphenols after multiple-dose administration of epigallocatechin gallate and polyphenon E in healthy individuals
Chow HH
Published in Clinical Cancer Research
Methodology
Randomized five-arm pharmacokinetic and safety trial with a 2-week run-in; 4 weeks of oral EGCG or Polyphenon E versus placebo; plasma catechin pharmacokinetics, safety labs and UV-induced erythema response.
Key Findings
40 healthy adults with Fitzpatrick skin type II or III were randomized to one of five 4-week regimens (800 mg EGCG once daily, 400 mg EGCG twice daily, the same doses as Polyphenon E, or placebo; 8 per group). All reported adverse events were mild and generally no more frequent than with placebo, and blood counts and chemistry were unchanged. Four weeks of dosing produced a greater than 60% increase in plasma EGCG area under the curve on the 800 mg once-daily schedule but no increase on the 400 mg twice-daily schedule, and the treatment gave no protection against UV-induced erythema.
Conclusions
Four weeks of green tea polyphenol treatment at the selected dose and dosing schedule did not provide protection against UV-induced erythema.
Limitations
Only 8 participants per arm, healthy volunteers with lighter skin types, 4-week duration, and the erythema outcome was exploratory rather than the primary endpoint.
Supplements Studied
Four weeks of green tea polyphenol treatment at the selected dose and dosing schedule did not provide protection against UV-induced erythema.
Related Health Concerns
Study Details
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