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Geranylgeraniol and Testosterone: What an 18-Week Trial Found

Geranylgeraniol did not raise testosterone across the group. But among men who started below 600 ng/dL, eight weeks at 300 mg a day lifted total testosterone by about 28 ng/dL — and CoQ10 held steady where placebo let it fall.

CE CASI Editorial Jun 16, 2026 5 min read 11 references
A Clinical Trial on Geranylgeraniol Supplementation for Testosterone Support in Middle-Aged Adults
Clinical Trial
11
Cited Studies
34
Participants
18
Week Trial

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