Thermogenesis

The 'coffee method' refers to using caffeine's thermogenic and appetite-suppressing properties to support weight loss. Caffeine increases energy expenditure by 8–11% acutely, suppresses appetite modestly, and enhances exercise performance. The evidence is real but modest — and tolerance limits chronic effects.

Metabolism boosters as a category encompass real physiological mechanisms and exaggerated marketing. This article applies evidence criteria to common claims, distinguishing documented effects (with realistic magnitudes) from unsupported assertions.

Certain dietary components genuinely increase energy expenditure through the thermic effect of food and thermogenic mechanisms. This article quantifies the evidence for protein, caffeine, capsaicin, green tea EGCG, and other dietary components on metabolic rate — with realistic effect size estimates.

Green tea contains two bioactive compounds — EGCG and caffeine — with documented effects on energy expenditure and fat oxidation. This article examines the mechanism, the quantified effect from clinical trials, and the conditions under which any benefit applies.

Caffeine does increase metabolic rate through thermogenesis — but the magnitude, mechanism, and limitations are specific. This article examines what the clinical evidence shows about caffeine's effect on resting metabolic rate, fat oxidation, and weight management.