# The Gut-Brain-Skin Link: Why Omega-3s and Probiotics Keep Showing Up in Skin Studies

_Evidence Level: Preliminary · Kim Y, Lee SJ, International journal of molecular sciences, DOI 10.3390/ijms27156814_

*The Gut-Brain-Skin Axis: Systemic Effects of Functional Ingredients in Healthy Skin Aging.*

- **Evidence Level**: Preliminary
- **Why this grade**: Narrative review pooling mechanistic, animal and heterogeneous human studies, with no integrated trials of gut, brain and skin endpoints in people yet.
- **Facts**: Design: Review
- **Publication Types**: Journal Article, Review
- **Journal**: International journal of molecular sciences
- **Sample Size**: N/A (review)
- **Authors**: Kim Y, Lee SJ
- **Graded and published**: 2026-07-29
- **Last edited**: 2026-09-17
- **Topics**: skin aging, gut microbiome, omega-3
- **DOI**: https://doi.org/10.3390/ijms27156814
- **Free full text**: https://pmc.ncbi.nlm.nih.gov/articles/PMC13466853/
- **Original Source**: https://pubmed.ncbi.nlm.nih.gov/42589469/

## Summary

Your gut, brain, and skin appear to talk to each other through immune signals, hormones, and bacteria-made molecules. This review argues that polyphenols, probiotics, and omega-3 fats may improve skin aging partly by working on the gut first, calming inflammation and shoring up barriers. Early human studies do show some improvement in skin measures and inflammation markers. But the trials are all over the map, and almost none measure gut, brain, and skin together.

## Practical Takeaway

This review suggests skin health may be linked to gut-focused nutrition, not just topical creams.

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_Canonical: https://longevity-germany.com/en/research/the-gut-brain-skin-link-why-omega-3s-and-probiotics-keep-showing-up-in-skin-studies · Part of Longevity Cities · Updated 2026-09-17_