Research

Hormonal

Green tea extract rich in catechins increases energy expenditure and reduces body fat in humans with higher brown adipose tissue (BAT) activities, likely through the activation of TRPV1/TRPA1 channels rather than COMT inhibition.

Drinking green tea extract rich in catechins daily may slightly reduce body fat (2-3%) if you have active brown fat. The benefit comes from the catechins, not just the caffeine. It is not a magic bullet and requires existing BAT activity to work.

GoodConditionalHIGH confidence
an oral ingestion of catechin-rich tea produced a rapid increase in EE in individuals with higher BAT activities, but not in those with undetectable BAT activities... the thermogenic and fat-reducing effects of green tea extract rich in catechins would be attributable to the activation of BAT
Masayuki Saito et al. · Frontiers in Endocrinology · 2020

Why this rating

Multiple human studies cited show consistent results in BAT-positive individuals, though one study showed no effect.

Source

Brown Adipose Tissue, Diet-Induced Thermogenesis, and Thermogenic Food Ingredients: From Mice to Men

Masayuki Saito et al. · Frontiers in Endocrinology · 2020

DOI 10.3389/fendo.2020.00222

narrative_reviewCited 234×
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DOI resolved against Crossref · corpus check 2026-06-10

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