# Why 17α-Estradiol Extends Lifespan in Male Mice but Not Females

*17α-Estradiol: A mildly feminizing estrogen with sex-specific metabolic and lifespan benefits.*

- **Evidence Level**: Preliminary
- **Publication Types**: Journal Article, Review
- **Journal**: Ageing research reviews
- **Sample Size**: N/A (review of preclinical studies)
- **Authors**: Santín-Márquez R, Fornalik M, Janovic SR, Isola JVV, Biswas S, Sathiaseelan R, Cox JEJ, Ocanas SR, Stout MB
- **Published**: 2026-05-15
- **Topics**: estrogen, lifespan, sex differences
- **DOI**: https://doi.org/10.1016/j.arr.2026.103182
- **Original Source**: https://pubmed.ncbi.nlm.nih.gov/42142594/

## Summary

17α-estradiol is a quirky cousin of the main estrogen hormone, and in mice it stretches lifespan and improves metabolism only in males. It trims body fat, sharpens insulin sensitivity, and protects the liver, with just mild feminizing effects. Scientists still don't fully know why males benefit and females don't. This is early-stage animal research, not yet ready for humans.

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_Canonical: https://usa-longevity.com/en/research/why-17-estradiol-extends-lifespan-in-male-mice-but-not-females · Part of Longevity Cities · Updated 2026-05-15_