The Claim

In lean, healthy men, a 5-week eucaloric diet with protein restricted to 9% of energy (0.8–1.06 g/kg/day) increases daily energy intake by 19–21% to maintain body weight, regardless of whether protein is replaced by carbohydrates or fat, indicating that protein restriction elevates metabolic demands for weight maintenance.

Source: Dietary protein restriction elevates FGF21 levels and energy requirements to maintain body weight in lean men

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
59score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

How it works
1 study reviewed
In plain English

When lean, healthy men consume a diet with very low protein for five weeks while maintaining the same total calorie intake, they naturally eat more food to keep their weight stable, suggesting that low protein intake increases the body’s energy needs for weight maintenance.

See the scientific wording

In lean, healthy men, a 5-week eucaloric diet with protein restricted to 9% of energy (0.8–1.06 g/kg/day) increases daily energy intake by 19–21% to maintain body weight, regardless of whether protein is replaced by carbohydrates or fat, indicating that protein restriction elevates metabolic demands for weight maintenance.

What the research says

1 study
  1. Study: Dietary protein restriction elevates FGF21 levels and energy requirements to maintain body weight in lean men

    When men ate less protein for five weeks, their bodies needed more calories to stay the same weight — no matter if they ate more carbs or fat instead. Their bodies just seemed to burn more energy when protein was low.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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