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SAMIRA IN KENTUCKY ASKS:
I got an online ad for a wool jog bra, which struck me as weird, but it got me thinking. Most athletic wear, like stretchy yoga pants, isn’t made of natural materials. I guess because polyester and spandex “performs” better. Are these materials safe? What’s the safest athletic wear?
Tell Congress: Protect Families From the Plastics and Petrochemical Industry
MOM DETECTIVE ANSWERS:
There was a time when I had what I can only describe as a mental block about my synthetic yoga pants, Samira. I’m no natural athlete, but I started doing yoga in my 20s and was proud to be doing something good for my health. I proceeded to sit in them pretty much daily—after every single sweaty class—for hours because I work from home. Why bother changing? I did this for probably a decade. Knowing what I know now, this is upsetting.
Even as I learned about the potential health harms of synthetic fabrics, it took me forever to put two and two together. By the time I did, I owned a lot of synthetic bras, leggings, and shorts—including those with the convenient built-in briefs. I did not know what to do. Throwing out an entire segment of a wardrobe isn’t environmentally friendly. And buying a whole new workout wardrobe isn’t cheap.
What’s unhealthy about synthetic fabrics?
Most sportswear is made from synthetic materials, you’re right. Polyester is common, so is spandex and nylon. The type of fabric often depends on the sport you’re dressing for. In general, lightweight materials can pull or “wick” sweat away from bodies, dry quickly, and be pretty durable. They’re also made of plastic, derived from petrochemicals (which come from fossil fuels), and can contain everything from flame retardants to harmful dyes to hormone-disrupting chemicals to heavy metals. They can also shed microplastics.
We all wear these fabrics pressed up against some pretty intimate places on our bodies. Chemicals in the fabrics can—and do—get into us via our permeable skin as we heat up and sweat, and via our lungs as we take in deep, full breaths. It’s a perfect storm.
But of what, exactly? Most fabrics don’t list on labels what dyes and finishing chemicals they are processed with so it’s hard to tell you specifically what’s safe and what’s not. And most studies about synthetic textiles and human health focus on rashes that pop up from wearing them. Synthetic athletic wear can trap bacteria and sweat close to your skin, causing irritation.
Still, we do know that formaldehyde, a classified human carcinogen, can be present in fleece—frequently used for athletic wear—as well as other textiles. It’s used to keep items from shrinking, and apparently, it can help with stain and mildew resistance. And we know that flame-retardant chemicals may be associated with a whole host of health harms, including learning disorders, reduced fertility, thyroid disruption, and cancer. When we wash a variety of synthetic fabrics after working out in them, tiny microfibers enter our waterways, where they threaten aquatic life, accumulate in the food chain (as in, tiny particles of your leggings can wind up in the fish you eat), and are persistent in the environment.
Alternative options
So what to do? If you’re shopping for new athletic wear, including socks, seek out cotton, organic cotton, hemp, and, yes, merino wool. It’s less weird than it sounds, and there are diehard hikers and marathoners that swear by it, even in hot weather. They claim it helps regulate temperature, wicks moisture, and also is resistant to odors.
Once you start reading labels, you’ll notice that a lot of natural items still have some synthetic material in them. You’ll have to decide for yourself what ratio—if any—seems acceptable. Be wary of fabrics like bamboo. It sounds natural, but the process of turning it into fabric can be chemically intensive. There are some reliable third-party textile certifications to guide you, like Global Organic Textile Standard (GOTS) and OEKO-TEX. Look for them.
What to do with what you already own?
I couldn’t stand to clog a landfill with all my uneducated purchases. My unscientific process went like this: I weeded out items that were pilling or very old as I felt these would also be the most likely to shed. And I wear a cotton barrier between my skin and synthetic fabrics I’ve kept when I can. I ran this idea past my dermatologist to see if it also made good common sense to him, and it did, but I haven’t seen a large study to back it up, so take it or leave it. A 100% cotton t-shirt is easy enough to wear under a fleece jacket, ditto a cotton tank top under a synthetic bra, but I admit I have yet to wear cotton tights under plastic yoga pants. That sounds uncomfortable. Cotton underwear? Yes! Cotton jog bra? Yes, please!
Also? No more sitting around. When I come home from working out, even if I’m just going to be writing at my desk for the rest of the day, I change out of anything synthetic and into cotton or wool items. Finally, I now only wash athletic wear in cold water and dry on a rack, not in a dryer. Heating plastic can cause it to break down and its chemical components to migrate.
What about kids?
Children’s sports uniforms are, in my experience, uniformly synthetic, usually polyester. And I also know some children will only wear certain kinds of fabrics. When it comes to these two scenarios, I suggest what I do with the synthetic items I still own: have kids wear a cotton layer between the skin and the uniform (if yours is willing) and change clothes to natural fabric ones after a game.
For kids, it’s also really important to teach them to wash their hands while wearing synthetic fabrics and before eating. There are frequently shared team snacks after a game, and if they have fibers from their uniforms on their hands as they eat, say, orange slices or cookies, that’s a direct route of ingestion from uniform-on-hands to mouth.
Don’t forget about gear
My final thought for you, Samira, as long as you’re reconsidering synthetic athletic wear is that there is plastic in a lot of workout gear too. There are PVC yoga mats and exercise balls, foam blocks, rubber mats, vinyl-covered weights and kettlebells, and so much more. These can be hard to avoid at a gym, but if you’re setting up a workout space at home, you’re in charge. There are safer alternatives in this realm too, like cotton and certified natural rubber mats, cork blocks, and cast-iron weights without plastic covers. Then you can stop thinking about plastic and get back to working out!
Tell Congress: Protect Families From the Plastics and Petrochemical Industry