The Claim

In healthy young adults, greater intra-individual variability in fecal serotonin levels during overfeeding is negatively associated with digestible energy absorption.

Source: Effect of short-term dietary intervention on fecal serotonin, gut microbiome-derived tryptophanase, and energy absorption in a randomized crossover trial: an exploratory analysis

What the research says

Supports is higher

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

Supports
68score
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.

Correlation
1 study reviewed
In plain English

In healthy young adults, larger fluctuations in fecal serotonin levels during overeating are linked to higher amounts of energy absorbed from food.

See the scientific wording

In healthy young adults, intra-individual variability in fecal serotonin levels is negatively associated with digestible energy absorption, meaning that individuals who experience greater drops in fecal serotonin during overfeeding tend to absorb more energy from food.

Why this might work

When a person eats more food than usual, the types of bacteria in the gut change, specifically reducing a group called Bacteroides. These bacteria normally break down a serotonin precursor into other compounds; when they decline, more of this precursor stays available, but less serotonin ends up in the stool. The drop in stool serotonin speeds up how fast food moves through the intestines, giving the body less time to let bacteria ferment nutrients and more time to absorb calories directly from the gut wall.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: Effect of short-term dietary intervention on fecal serotonin, gut microbiome-derived tryptophanase, and energy absorption in a randomized crossover trial: an exploratory analysis

    When people eat more than usual, their poop serotonin levels drop — and the bigger that drop, the more calories their body absorbs. This study found that link in healthy young adults.

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

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