Green tea extract

What it is

Green tea extract concentrates the catechins in green tea, chiefly EGCG, and usually contains caffeine too. It is a different proposition from drinking brewed tea — both any effect and a real safety concern come from the concentration.

What the evidence shows

Fat oxidation and weight loss. Preliminary· human data Its catechins may slightly increase fat oxidation and energy expenditure, but the real-world effect on body weight is small and often depends on the caffeine it contains. It is a minor lever, not a solution.

Who it suits

There is little strong case for it as a fat-loss aid. Brewed green tea is a safe, pleasant habit; high-dose extracts are where the risk-benefit balance tips.

Practical notes

Concentrated EGCG extracts have been linked to rare but serious liver injury, particularly when taken on an empty stomach — a concern that does not apply to drinking tea. If you use one, don't take it fasted, and stop at any sign of liver trouble such as jaundice, dark urine or abdominal pain. Remember it also contributes caffeine to your daily total.

Sources

PubMed: green tea extract / EGCG — fat oxidation, weight loss and hepatotoxicity (reviews and case reports)

Frequently asked questions

Does green tea extract burn fat?

Its catechins (chiefly EGCG) may slightly increase fat oxidation and energy expenditure, but the real-world effect on body weight is small and often depends on the caffeine it contains. It's a minor lever, not a fat-loss solution.

Is it the same as drinking green tea?

No. Concentrated extracts deliver far more catechins than a cup of tea, which is where both any effect and the liver-safety concern come from. Drinking brewed green tea is a safe, pleasant habit; high-dose extracts are a different proposition.

Is it safe?

Brewed tea is fine, but concentrated extracts have been associated with rare cases of liver damage. If you use one, avoid taking it on an empty stomach and stop at any sign of liver trouble.