metabolic · Outcome
Lean mass to fat mass ratio. The goal for most people is gaining or holding lean while reducing fat, not just losing weight.
How to measure: DEXA scan every 3-6 months, BIA weekly trend, waist circumference monthly. Mirror and lifting numbers also track honestly if you measure consistently.
Three levers, one stack. Each works through a different mechanism. They compound.
3.2% less body fat
20-40 g per serving, supporting 1.6-2.2 g/kg total daily · Anchor 1-2 servings to meals you would otherwise skip
Effect size
Corpus
64 papers
range 0.3–37 · n=10 quantitative claims
“Whey protein combined with resistance training decreased fat mass in middle-aged untrained men.”
Why: The biggest lever for body comp isn't fat burning, it's keeping muscle while losing fat. High protein intake during a cut is the difference between losing 80% fat and 50% fat.
See the studies2.8% less body fat
10-20 hard sets per muscle per week · 2-4 sessions weekly
Effect size
Corpus
169 papers
range 0.7–30 · n=34 quantitative claims
“Time-restricted feeding resulted in greater fat mass reduction (TRF: -2% to -4%; control diet: +2%) in per-protocol analysis but not in intention-to-treat analysis.”
The most reliable way to look 'leaner' at the same body weight. Skipping resistance training during a fat-loss phase is the most common reason people lose weight but still look soft.
Small effect
200-300 g · Mid-morning or evening snack
Effect size
Corpus
None
Why: The best single-food swap for people who graze. ~20 g protein per cup at 130-150 kcal beats almost any packaged snack.
See the studiesEverything we found, ranked by how strongly we recommend it. Tap any to see the studies.
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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 body composition, in the units that matter for this outcome.
Confidence
How sure are we the effect is real for body composition, given the studies we have.
For every pick, the “papers” number is how many studies we've cataloged that test this entity for body composition. “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 body composition.
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