Two hikers taking a break

For many people who love the outdoors, a Gore-Tex rain jacket and leather hiking boots are nonnegotiable. Some vegetarians who buy only organic produce won’t live without their Lululemon yoga pants. But a smaller number of people may be ready to commit to only using natural fibers even for their performance wear. Those deep-green people can find sustainable options. You might even be surprised by how functional some of them really are.

Chemical Clothing

By definition, synthetic fabrics are made out of chemicals that are ultimately traced back to oil. Petrochemical-based synthetics make up 65% of all fibers produced annually. Polyester is by far the most widely used synthetic fabric, but acrylic, nylon, vinyl, and many “vegan leathers” are made from oil, with a carbon footprint to match. A polyester T-shirt emits an estimated 5.5 kg CO2-eq while a T-shirt made from cotton, which is not exactly a low-impact material, produces only 2.1 kg CO2-eq.

Synthetic fabrics also contribute to plastic pollution, releasing microfibers from the washing machine into wastewater. These fibers eventually make their way to the ocean as microplastic pollution. Performance coatings add more toxins and pollutants. Waterproofing treatments like Gore-Tex are made from petrochemicals, usually polyurethane, and often contain PFAS as well. PFAS protect clothing from stains and contribute to waterproofing. But they are associated with serious elevated health risks. These forever chemicals enter the environment both when clothes are washed and when they are discarded.

Waterproof Gear

Gore-Tex has become the gold standard of waterproofing, and fortunately a newer version used in some product lines replaces PFAS with expanded polyethylene. It’s safer, but it’s still a synthetic coating. Before there was Gore-Tex, fishermen and sailors wore oilcloth (also called oilskin) to protect them from extreme weather. Traditionally, people made oilcloth with close-woven cotton duck or linen cloth coated in boiled linseed oil.

In the 1830s, synthetic wax began to replace oil. Most fabric sold as “oilcloth” or waxed cotton today is coated in PVC or paraffin wax, both of which are petroleum based. But oilskin was always a DIY fabric, and you can still make your own today. You can also create your own waxed cotton using beeswax or Otter Wax, a proprietary blend of bees’ and plant-based waxes. Oilcloth and waxed cotton are effective waterproof options and have an appealing retro aesthetic. But they are heavier and stiffer than synthetic options. They also require regular maintenance and do not breathe like contemporary high-tech fabrics.

Woman wearing warm wool sweater overlooking snowy scene
For warmth and water resistance, it’s hard to beat sheep’s wool. Look for products with certifications from IWTORWS, or Woolmark.

Warm and Water Resistant

Nothing beats the chill on an autumn evening or resists a drizzly day better than fleece. But fleece is a type of polyester and is made from the same material as plastic beverage bottles. That’s a good thing if you can find recycled fleece. But even recycled synthetic fabrics generate microplastic pollution, and usually cannot be recycled themselves.

Fortunately, there is a very old solution to the problem – wool. In Iceland, where the weather conditions are very challenging, the traditional woolen lopapeysa sweater is still much more popular than fleece. There are some natural, vegan alternatives to wool, but for warmth and water resistance, it’s hard to beat sheep’s wool. Look for wool products with one of these certifications: International Wool Textile Organization (IWTO), Responsible Wool Standard (RWS), or Woolmark.

If you find wool itchy, remember that you usually wear a layer underneath fleece anyway. And if you are comfortable with wool against your skin, at least one brand makes merino wool athletic wear, and another does so with alpaca wool.

Athletic Wear

It’s hard enough to drag yourself to the gym. Working out in clothes that pull instead of cling, sag instead of stretch, and get soggy instead of wicking sweat is enough to make anyone stay home. But Spandex and polyester are both synthetic fabrics. Fortunately, active wear manufacturers are starting to reconsider natural fabrics for performance clothing. Lululemon recently introduced a shirt made from plant-based nylon.

The most common brand name – and one of the most sustainable options – for lyocell and modal cellulosic fibers is Tencel. These cellulosic fibers are made from certified wood and recycled solvents and behave much like performance polyesters. Vyayama is one brand offering Tencel yoga clothes. Vegan brand Organique Studio uses both Tencel and organic cotton in its unique active wear designs. Certified B Corp PAKA steps outside the yoga studio, using Tencel and alpaca wool to make hoodies, shorts, joggers and socks.

When people exercised before the invention of performance fabrics, they were usually wearing 100% cotton. Cottonique uses only GOTS-certified cotton in its sports bras, T-shirts, shorts and socks. Sometimes the oldest, simplest solutions are still the best.

By Gemma Alexander

Gemma Alexander has an M.S. in urban horticulture and a backyard filled with native plants. After working in a genetics laboratory and at a landfill, she now writes about the environment, the arts and family. See more of her writing here.