The provenance of your shirt, pants, and underwear isn’t just aesthetic or ornamental. It’s serious stuff. Consider food, which isn’t that different from clothing. Textile production is an industrial process, with all the economies of scale and chemical adulteration that entails. Just as processed food bears increasingly little resemblance to whole food, clothes are not “whole textiles.” They are processed junk fabric enhanced with plastic fibers and many of the same chemicals we try to limit in our foods.
But there’s better clothing out there, just as there’s better food. There’s clothing made of sustainable fabric—fabrics that sustain life, rather than detract from it.
When I say “sustainable,” I’m not thinking about the planet as much as I’m thinking about the health of my own body and my family’s. For if something is going to be sustainable on a global level, it must first be a sustainable fabric for the individual. It has to support the life of the organism that populates the planet and is indeed part of the planet. Again, let’s refer back to food. If a diet isn’t compatible with good health in the population, how can it be good for the planet? Is there any situation where a diet heals the planet and its biological systems while leaving the individual animals who eat it sickly, diseased, weak, and infertile? Of course not.
For clothing to be made with truly sustainable fabric, it must be good for individual healthand the environment. No other definition of “sustainable” is acceptable. And so when determining the sustainability of a given fabric, we have to consider the health impacts.
The Best Sustainable Fabrics
Cotton is the most common and widely available natural fiber, but it’s also very popular with the bugs. Cotton plants produce nutritious and energy-dense fruits throughout the growing cycle, making it irresistible and leading to heavy pesticide usage. Conventional cotton is the most heavily treated crop in the world, responsible for a lion’s share of total global pesticide applications—despite covering just a fraction of the world’s cropland.
GMO cotton engineered to repel the most common cotton pests with an in-house toxin worked briefly but ultimately led to resistance to the engineered toxin, necessitating more pesticide usage and triggering a chemical arms race between farmers and pests that continues to this day.1 In fact, Indian cotton farmers use more pesticides now than they did before the introduction of GMO cotton.2
I was unable to find any evidence of the pesticides used in cotton production residing in the finished fabric and then leaching into human skin, but skin is permeable. These things happen. Washing reduces any surface-level chemicals added to the cotton, but those bound to the fibers itself may remain. Again, there’s not a lot of research on this topic, perhaps because it’s one they’d rather not broach.
Linen is an ancient sustainable fabric with prehistoric roots—as far back as 30,000 years in present-day Georgia and 10,000 years ago in Switzerland, humans were extracting and dyeing wild linen fibers.34 Throughout Medieval Europe, North Africa, and Central Asia, linen was a common fabric used for undergarments, tunics, dresses, and anything that lay close to the skin.
Linen is perhaps my favorite fabric at the moment. It’s almost required to live in Miami during the hottest months. You can almost feel cooler wearing a linen shirt and shorts in the humid heat than you do wearing nothing at all. Linen isn’t just less bad than cotton or synthetics in the heat. It’s actively cooler. It breathes and wicks moisture from your body. It improves in the heat and humidity. The more you wear it and wash it, the softer it gets.
Linen is naturally anti-bacterial, making it the best and most hygienic choice even today for hospital bedding (why they call them “linens”). This quality also means linen doesn’t hold odor as much as other fabrics. It’s such a sustainable fabric that you can hang a linen shirt up to air out after wearing it and there’s a good chance it’ll be good for another day or two.
Wool is another ancient fabric. If linen is great for hot muggy weather, wool is downright designed by the hand of evolution to provide insulation against the cold. You can stay active in it because it repels bacteria, doesn’t get very smelly, breathes and wicks moisture. It’s even a little resistant to water if the natural lanolin—a fatty substance present in “raw” wool that keeps sheep from getting totally soaked—remains or is added back into the fabric.
Wool can be scratchy, but merino wool is a softer, silkier variety that feels much smoother and “cotton-like.” Merino wool is more expensive than normal wool.
Tencel is a sustainable fabric, very similar to rayon, that uses wood pulp with a non-toxic solvent to help it become fabric. Tests show that any residuals of the solvent are eliminated in the finished product, and clothes made with tencel fabric are biodegradable.
Things to Keep in Mind When Choosing Sustainable Fabrics
Trust but verify.
Some otherwise sustainable fabrics, like wool in one notable case, can be treated with BPA and other plasticizers to increase thermal stability and overall resilience, with one study even finding that wool had more BPA than polyester blends.5 If you buy wool, cotton, linen, or hemp clothing, be sure to research the manufacturer and confirm that they do not add plasticizers to their fabric. But for the most part, any sustainable fabric is going to be a better, safer choice than any polyester or polyester-blend.
Avoid stain-resistant and water-repellant clothing.
PFAS, the “forever chemicals” linked to fertility issues, hormonal changes, and chronic health conditions that end up in our food, water, and salt, are also used to make fabrics stain-resistant and water-repellant. They can be added to any fabric, but aren’t usually incorporated into the sustainable fabrics listed above.
Obviously, water repellant gear can really come in handy when you need it. Backpacking through the Pacific Northwest or along Kauai’s Na Pali coast? Wear the rain gear. Especially since that kind of rain outwear doesn’t ‘really touch your body as much. But don’t make it a habit to wear “water repellant” and “stain resistant” clothing on an everyday basis.
Avoid wrinkle-free fabric.
Wrinkle-free usually means “dosed with formaldehyde.”
A pair of interesting dog studies showed the harmful anti-fertility effects of wearing polyester. One study in intact male dogs had them wear either polyester or cotton underwear for a few weeks. The underwear was loose enough not to affect scrotal temperatures, and yet the polyester fabric impaired sperm quality, motility, and overall fertility. The sustainable fabric—cotton—had no effect on fertility measures.
Another study placed garments made from different fabrics on pregnant dogs. One group wore wool, one wore cotton, one wore a cotton-polyester 50/50 blend, and the final group wore 100% polyester. All dogs wore their garments for the duration of the pregnancy. The wool, cotton, and cotton/poly blend dogs all had normal pregnancies with normal hormone levels throughout, while the polyester dogs were more likely to have issues.6
Finally, a pair of followup studies in human men explored the polyester issue further. One study split men up into three groups. One group wore cotton underwear, one group wore a cotton/polyester 50/50 blend, and the final group wore underwear made out of pure polyester. While the cotton underwear produced no electrostatic charge across the scrotal sac, both the blend and the polyester did, with the polyester underwear creating the strongest (and most detrimental) charge.7
Another study split men into 5 groups: a control group wearing their regular clothing, a group wearing only cotton underwear, one wearing only wool, another wearing a cotton/poly blend, and a final group wearing just polyester. They established a baseline and then tracked how their sexual activity (or “potency”) changed over 12 months. The cotton and wool groups were most unchanged. The cotton/poly blend and polyester groups saw their sexual potency diminish significantly, with the pure polyester group having the worst results.8
Watch the leggings and yoga pants.
A recent study found that many popular legging brands, like Lululemon and Old Navy, may also contain the forever chemicals PFAS. Not all of the samples did, mind you, but a good enough portion to be careful or even consider other brands.
Wear plain shirts.
Printed graphics on fabrics are the primary source of dermal exposure to caustic chemicals like benzothiazole. Studies of human skin show that simulated “wearing” of clothing with residual benzothiazole and other related compounds leads to dermal absorption.9 The risk is higher in infants wearing socks with benzothiazole, as the increased skin temperature facilitates absorption. Up to 86% of baby clothing (socks, body suits, shirts, etc) samples in one study had measurable residues.10
Mind your genitals.
Ever since modern humans arrived, we’ve been covering our genitals with fabric. That means just about every hour of the day, you’ll have to wrap your genitals in some kind of fabric. You can be shirtless at the beach but you’ll still cover your genitals. You can be walking out in your boxers to get the paper but you’ll still be covering your genitals in fabric. My point and reason for writing the word “genitals” so much is that they’re a special part of the body that’s uniquely vulnerable to poor clothing choices. If you have to wear something down there, use sustainable fabric.
The human genitals are an incredible sensitive zone covered in permeable skin, making them a prime entry point for topical medicine and uniquely vulnerable to the absorption of unwanted, harmful chemicals. The problem is that a lot of underwear is absolutely riddled with anti-fertility or estrogenic chemicals.
How to Make Good Choices about Sustainable Fabrics
Make good choices when and where you can.
Don’t wear snug fitting plastic (polyester) underwear. Maybe don’t wear underwear at all.
Limit or eliminate print tees.
Limit water-resistant or stain-resistant clothing.
Limit wrinkle-free clothing.
Buy your leggings and yoga pants carefully.
Focus on quality over quantity. Be willing to spend a little more for better feeling, “healthier” more sustainable fabrics that last longer.
If you’re dressing your baby or child, spend the money on quality stuff. At the very least, minimize child clothing with prints and graphics and aim for natural fabrics.
Buy natural sustainable fabric like organic cotton, linen, and wool whenever possible and realistic.
Visit thrift stores for well-worn natural sustainable fabric clothing that’s had plenty of time to leach out most of its chemical load.
Blends are better than nothing. Remember that most of the studies discussed above found that cotton-polyester blends were less harmful (and in some cases totally harmless) than pure polyester clothing.
Sustainable Fabric Brands
What are some good brands to get you started on your sustainable fabric journey?
Everlane: Nice clothing whose site can be filtered by fabric. Here’s linen, here’s organic cotton. And so on.
Amazon: You can find some great deals on sustainable fabric clothing on Amazon. Just type in “organic cotton shirt” or “linen dress” or whatever. Make sure you vet the vendors, as Amazon listings aren’t always the most reliable.
Etsy: You can also find some great stuff on Etsy, a marketplace for small makers. Here’s “organic merino wool shirt,” for example.
Outdoor gear: This is a good guide to finding PFAS-free outdoor gear. Not all of the fabric is sustainable or natural, however.
You know when you touch linen or wool. Your brain understands the difference between silk and linen, cotton and wool, synthetics and naturals on a somatosensory level, simply by touch.11 The differences are real, and the studies probably aren’t capturing everything that distinguishes them.
I’d love to see studies into the effects of different fabrics on heart rate variability for example. I’d bet there are real differences in people wearing linen or wool versus polyester. When I wear linen, I know the difference. You just feel better, more at ease, more at home.
Despite all the somewhat troubling research discussed today, don’t lose sleep over your clothing. You’re already eating well, sleeping well, getting sun, getting out into nature, exercising on a regular basis, and all the other good things we emphasize around here. Freaking out about some chemicals on your T-shirt is only worthwhile—and even then, arguably so—if you’ve already taken care of the low hanging fruit and want something else to occupy your time.
Don’t let perfect be the enemy of the good. I own some synthetic exercise stuff myself, and it’s hard to beat for performance. That said, I’m not wearing it all the time and I’m not wearing pure polyester gear. I’m using it for specific instances: hikes, running, paddling, Ultimate Frisbee, workouts. I’d love to train hard in linen shorts or something like that, but it just doesn’t flex like synthetic active wear.
If you find yourself avoiding workouts because you haven’t found the perfect pair of totally toxin-free shorts, you’re missing the forest for the trees.
What’s your favorite sustainable fabric to wear? Got any goods brands you’d like to share?
Mark Sisson is the founder of Mark’s Daily Apple, godfather to the Primal food and lifestyle movement, and the New York Times bestselling author of The Keto Reset Diet. His latest book is Keto for Life, where he discusses how he combines the keto diet with a Primal lifestyle for optimal health and longevity. Mark is the author of numerous other books as well, including The Primal Blueprint, which was credited with turbocharging the growth of the primal/paleo movement back in 2009. After spending three decades researching and educating folks on why food is the key component to achieving and maintaining optimal wellness, Mark launched Primal Kitchen, a real-food company that creates Primal/paleo, keto, and Whole30-friendly kitchen staples.