Polyester is the New Birth Control? The Truth About Activewear & Hormones

They tell us to eat clean, work out, and prioritize wellness.
But then they sell us $200 leggings made of polyester and nylon — plastic fabrics that sit tight against our skin while we sweat.
Here’s what the wellness industry doesn’t want you to know: polyester and other synthetics aren’t just uncomfortable. Studies show they can leach hormone-disrupting chemicals like PFAS, BPA, phthalates, and antimony into our bodies. And the effects? They may contribute to irregular cycles, fertility struggles, mood swings, and hormone imbalance.
In this video, I’m exposing the history, the science, and the marketing lies behind “performance wear.” Because women deserve the truth about what we’re putting on our bodies — not just what we put in them.

Studies & Sources Mentioned
1. Shafik A. Contraceptive efficacy of polyester-induced azoospermia in normal men. Contraception. 1992.
2. Biver M, Turner A, Filella M. Antimony release from polyester textiles by artificial sweat solutions. Regul Toxicol Pharmacol. 2021.
3. Xia C, et al. Per- and Polyfluoroalkyl Substances in North American School Uniforms. Environ Sci Technol. 2022.
4. CEH (Center for Environmental Health). New Testing Shows High Levels of BPA in Sports Bras and Athletic Shirts. 2022.
5. The Guardian. Thread carefully: your gym clothes could be leaching toxic chemicals. 2023

Healthier Fabric Swaps
If you want to cut down your exposure, here are three better options for next-to-skin pieces like sports bras, leggings, and underwear:

Organic Cotton – breathable, natural, GOTS-certified for fewer toxins.
Merino Wool – temperature-regulating, odor-resistant, moisture-wicking without chemicals.
Tencel (Lyocell) – sustainably made from wood pulp, soft, breathable, and gentle on skin.
Look for certifications like:
OEKO-TEX® Standard 100 (tested for harmful substances, including PFAS)
GOTS (Global Organic Textile Standard)
bluesign® (ensures safer chemicals and cleaner supply chains)