The Claim

In late-pregnant Yili mares, daily supplementation with 30 grams of L-citrulline significantly increases fecal microbiota diversity (as measured by Chao1, Shannon, and Simpson indices) and enriches bacterial taxa including Lachnospiraceae, Saccharofermentans, and Fibrobacter.

Source: The Effects of L-Citrulline on the Apparent Digestion and Metabolism of Nutrients, Blood Hormone Levels, Amino Acid Metabolism and the Diversity of Faecal Microbiota in Mares in the Later Stage of Pregnancy

What the research says

Supports is higher

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

Supports
19score
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.

Cause and effect
1 study reviewed
In plain English

In late-pregnant Yili mares, daily intake of 30 grams of L-citrulline increases the diversity of gut bacteria and raises the abundance of specific bacterial groups including Lachnospiraceae, Saccharofermentans, and Fibrobacter.

See the scientific wording

In late-pregnant Yili mares, daily supplementation with 30 grams of L-citrulline significantly increases fecal microbiota diversity (Chao1, Shannon, Simpson indices) and enriches beneficial bacterial taxa including Lachnospiraceae, Saccharofermentans, and Fibrobacter, suggesting improved gut microbial ecology during late gestation.

Why this might work

L-citrulline is absorbed and turned into arginine, which makes nitric oxide that improves blood flow and reduces harmful oxidative stress. This creates a better environment in the gut for fiber-digesting bacteria to grow. At the same time, the extra nitrogen from L-citrulline feeds these bacteria, helping them break down plant fiber more efficiently and produce compounds that strengthen the gut lining. Together, these changes increase the number and variety of beneficial bacteria in the gut.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: The Effects of L-Citrulline on the Apparent Digestion and Metabolism of Nutrients, Blood Hormone Levels, Amino Acid Metabolism and the Diversity of Faecal Microbiota in Mares in the Later Stage of Pregnancy

    Giving pregnant horses 30 grams of L-citrulline every day made their gut bacteria more diverse and healthier, just like the claim said.

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

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Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.