EGCG (green tea) — The Major Green Tea Catechin

EGCG acts as a powerful antioxidant and modulates multiple signaling pathways implicated in aging. It activates AMP-activated protein kinase (AMPK), which promotes metabolic homeostasis and autophagy. EGCG also inhibits the mechanistic target of rapamycin (mTOR) pathway, mimicking aspects of caloric restriction. Furthermore, it suppresses NF-κB signaling, thereby reducing chronic low-grade inflammation (inflammaging), and has been shown to influence epigenetic regulation by inhibiting DNA methyltransferases (DNMTs).

Numerous epidemiological studies link green tea consumption to reduced all-cause mortality and lower risks of cardiovascular disease. Clinical trials have demonstrated that EGCG supplementation can improve metabolic markers, such as insulin sensitivity and lipid profiles, and reduce markers of systemic inflammation. However, specific human trials designed to measure direct lifespan extension are lacking.

Typical supplemental doses range from 200 to 800 mg of EGCG per day, often divided into two doses. It is frequently consumed as green tea extract. To maximize absorption, it is best taken on an empty stomach, though this increases the risk of nausea. High doses (above 800 mg/day) should be avoided due to potential hepatotoxicity.

EGCG is generally safe at dietary levels, but high-dose supplements can cause gastrointestinal distress, nausea, and in rare cases, liver toxicity (hepatotoxicity). It may interfere with the absorption of non-heme iron and can interact with certain medications, including beta-blockers and blood thinners. Individuals with liver conditions should consult a physician before taking concentrated EGCG extracts.

Key Papers