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Guarana and caffeine effects

The effects of guarana and caffeine on energy expenditure and weight loss

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Jan 30, 2026
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What clinical evidence exists for the key ingredients listed in Gelatide (raspberry ketones, green tea extract, guarana)?

have convincing mechanistic data from cell and animal work but essentially no robust human evidence supporting weight loss when used alone; clinical trials are very limited and often combine raspberry...

Jan 11, 2026

Are the active ingredients in Flash Burn clinically studied for weight loss or fat-burning, and what does the evidence say?

Flash Burn’s ingredient roster — green tea (EGCG), guarana/caffeine, capsicum (capsaicin), African mango (Irvingia gabonensis), L‑carnitine, grape seed and others — includes plant extracts that have b...