In healthy women, consuming 2 or 3 grams of leucine peptide does not change levels of the gut hormone PYY after eating, compared to a control bar.

Pro

Against

Mechanism

Synthesis from 1 study

How it works

Leucine makes you feel full after eating, but it doesn't do this by triggering the PYY hormone. Instead, it uses a different biological route to tell your brain you're satisfied.

Most probable mechanism

In Simple Terms

When leucine is absorbed after eating, it triggers feelings of fullness without increasing the hormone PYY, meaning the brain receives satiety signals through a different pathway that does not involve this gut hormone.

Causal chain

Leucine peptide is digested and absorbed into the bloodstream, causing a dose-dependent increase in plasma leucine concentration.

Verified by multiple studies

which leads to

Elevated plasma leucine activates nutrient-sensing pathways in enteroendocrine L-cells or other gut cells, but this does not result in increased secretion of peptide YY.

Supported by evidence

which leads to

Satiety signals are transmitted to the hypothalamus and brainstem through an alternative mechanism not involving peptide YY, leading to reduced hunger and increased fullness.

Supported by evidence

Evidence from Studies

Supporting (1)

Community contributions welcome

Consuming Lower-Protein Nutrition Bars with Added Leucine Elicits Postprandial Changes in Appetite Sensations in Healthy Women.

Randomized Controlled Trial

Human

2018 May 1

Contradicting (0)

Community contributions welcome

No contradicting evidence found

Gold Standard Evidence Needed

According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.

Source Study

Consuming Lower-Protein Nutrition Bars with Added Leucine Elicits Postprandial Changes in Appetite Sensations in Healthy Women.

Score: 59

DOI: 10.1093/jn/nxy023

Similar Assertions

When healthy women eat nutrition bars with 0, 2, or 3 grams of added leucine peptide, their blood leucine levels rise proportionally to the dose, but their feelings of fullness and peptide YY levels do not change in a corresponding way.

89%

In healthy women, consuming a 3-gram leucine peptide supplement does not reduce hunger or desire to eat more than a control bar, even though it raises blood leucine levels more than a 2-gram dose, showing that higher leucine levels do not proportionally reduce appetite.

78%

A nutrition bar with 11 grams of protein and 2 grams of leucine peptide produces the same level of fullness after eating as a bar with 13 grams of protein and 3 grams of leucine peptide in healthy women.

76%

In healthy women aged approximately 28 years, a 180-kcal nutrition bar with 2 grams of added leucine peptide increases feelings of fullness after eating and reduces the desire to eat more later, compared to a similar bar without leucine, even when both bars have the same calories and protein.

74%