I spend most of my clinical time thinking about what goes into the body. Food, supplements, medications, water. At some point you have to widen the frame, and fabric is where a lot of people have not looked yet.
The skin is the body’s largest organ. Transdermal drug delivery works precisely because the skin absorbs compounds, and it does not selectively absorb only things we intend. What sits against it for sixteen hours a day matters. This is especially true before, during, and after cancer treatment, when metabolic and hormonal pathways are already under stress.
The problem with synthetic fabrics
Most clothing is polyester, nylon, acrylic, or spandex, often blended. The fibers themselves are one issue. The finishing chemicals applied during manufacturing are another.
Fabrics are routinely treated with:
Formaldehyde-releasing resins for wrinkle resistance
PFAS for water and stain repellency
Azo dyes that can release carcinogenic aromatic amines
Phthalates as softeners and plasticizers
Flame retardants, particularly in children’s clothing and sleepwear
Nonylphenol ethoxylates, weak estrogen mimics left over from textile processing
For anyone navigating a hormone-driven cancer, including ER-positive breast, endometrial, or prostate cancer, reducing exogenous compounds that interact with estrogen or androgen pathways is a reasonable clinical goal. Fabric is part of that conversation.
There is also the microplastic issue. Synthetic fabrics shed microplastics with every wash and every wear. These are now measurable in human blood, placenta, and breast milk. We do not yet have a clean dose-response story, but I am not waiting for one.
Where to start
Prioritize what touches your skin the longest and most directly:
Underwear and bras
Sleepwear (eight hours of uninterrupted skin contact in a warm environment that increases absorption)
Workout clothing, which is almost universally polyester or nylon, often with added “antimicrobial” chemical treatments
Bras, chest-area and underwear and garments (chest and pelvic areas are the largest area of lymph drainage)
Brands worth knowing
For underwear and everyday basics: Pact and Mate the Label are GOTS-certified organic cotton at an accessible price point. TomboyX, Odd Body, and Skin Worldwide cover inclusive sizing in cleaner materials. Jungmaven and Groceries Apparel make organic cotton and hemp basics. Le Bon Shoppe for softer knits and loungewear. DONNI layers in beautifully here too, with soft cotton and silk pieces that wear like a second skin.
For sleepwear: Lunya makes washable silk, which is best for temperature regulation and makes going to bed feel like luxury every night.
For sleepwear and bedding: tbco is my favorite for fun-pattern-cottons that invite layering and personal styling. Sønderhaus is another worth knowing, Scandinavian linen loungewear and bedding that reads calm and considered.
For activewear: Woolly Clothing and Organic Basics both have natural fiber options. Icebreaker and Smartwool make merino wool activewear that works well for yoga, walking, and lower-intensity training.
For yoga and studio wear specifically, Indigo Luna, HARA the Label, Studio K, Bodypeace Bamboo, bai active, and Pinky and Kamal are all doing natural and low-tox fabrics well. Reprise Activewear and OLESSA round this category out.
A note on activewear: Bamboo clothing is often marketed as “natural,” but most bamboo fabrics (viscose or rayon) are heavily processed with chemical solvents. By the time they reach your skin, they are far removed from the original plant. Tencel (lyocell) is a reasonable middle ground. It is semi-synthetic, but made in a closed-loop process with significantly less chemical exposure than conventional rayon. If you can, choose less processed fibers like cotton, wool, hemp or linen. They carry a lower chemical burden and tend to be more breathable.
For elevated staples: Assembly Label, Nude Lucy, aere, and Posse are worth exploring for linen and quality cotton. ARCAA Movement, Rowie the Label, and Maurie and Eve lean into quality cottons with a clean aesthetic. La Relaxed, Wear Kent, and SKFK round out this category. Quince remains one of the most accessible options for linen, organic cotton, and cashmere without the luxury price tag. On the opposite side, babaà is worth the hype, they make hand-knit cotton and wool sweaters out of Spain that last for years and get better with wear, but are expensive! Which brings me to my next topic.
The case for buying second-hand
Buying a used linen blazer or silk blouse is a better choice than buying new natural fiber, because it removes demand for new production entirely and significantly reduces your exposure to finishing chemicals, which break down with repeated washing over time. It also cuts textile waste and microplastic pollution in a way that buying new, even from the best brands, does not.
For online resale with a sustainability focus: Noihsaf Bazaar curates higher-quality natural fiber pieces and is worth bookmarking. Depop skews younger but has strong vintage linen and wool finds if you search by material. ThredUp is the highest volume option and has a filter for fiber content. The Real Real is useful for silk, cashmere, and wool at the higher end. Vestiaire Collective for European natural fiber brands that do not always make it to US resale markets.
If you are in Seattle, I shop Hoste, Ere, Editor Consign, Creature Consign, Friend Museum, and Bon Voyage Vintage specifically for natural-fiber finds. The quality of what comes through consignment in this city is genuinely good.
Certifications worth knowing
OEKO-TEX Standard 100 means the finished fabric has been tested for a list of harmful substances. GOTS certification covers the full organic supply chain. Both are searchable on brand websites and worth verifying before you buy.
Avoid labels that read “wrinkle-free,” “stain-resistant,” “water-repellent,” or “antimicrobial.” These almost always signal chemical treatments.
The bottom line
You do not have to replace your entire wardrobe… but going forward you should start investing in natural fiber clothing. Start with sleepwear, then underwear, then workout clothing. Build from there at whatever pace makes sense. The goal is not perfection. It is a lower total exposure burden over time, and these are some of the easiest swaps to make.
Very nice summary. What shocked me recently is a sweatshirt I bought that said “Keep away from fire.” That’s a new one. It’s on its way back to the seller. No questions asked (on my side).