metabolic · Outcome
Burn fat between meals. Burn carbs around training.
How to measure:
Three levers, one stack. Each works through a different mechanism. They compound.
Noticeable
100-200mg
Evidence
Effect size
Research
8 papers
6 small · 13 moderate · 0 large · 3 unclear
“Catechin-caffeine mixtures increased 24-hour fat oxidation by 12.2 g (16.0%) compared to placebo.”
Noticeable
45-120 min, 3-4x per week
Evidence
Effect size
Research
12 papers
1 small · 24 moderate · 5 large · 1 unclear
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We only surface a food once enough quality studies back it for this goal. None clear the bar yet. We add new research daily, so this can fill in soon.
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Every pick has two signals. They answer different questions and we never bundle them into one number.
Effect size
How big is the change on metabolic flexibility, in the units that matter for this outcome.
Confidence
How sure are we the effect is real for metabolic flexibility, given the studies we have.
For every pick, the “papers” number is how many studies we've cataloged that test this entity for metabolic flexibility. “Favorable” means the study reported the direction you want.
The tier badge (S, A, B…) on the entity itself is its overall research confidence across all outcomes. It's the same letter wherever you see this entity on the site, not specific to metabolic flexibility.
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“Exercise training at maximal fat oxidation intensity (FATmax) improves maximal oxygen uptake (VO2max) in people with overweight or obesity.”