95% of products that touch your skin are made of plastic.
We review every activewear brand so you don't have to. Only natural fabrics make the cut.
Independent reviews. Fabric science. No greenwashing.
95% of activewear is made from plastic.
Polyester
Petroleum-based. Takes 200+ years to decompose. Sheds microplastics every wash.
PFAS
Hormone-disrupting ‘forever chemicals’ found in major activewear brands. Your skin absorbs them.
Microplastics
A single polyester garment releases 700,000 microplastic fibers per wash. Into your water. Into you.
Your leggings shouldn't be a health risk.
You are wearing plastic.
95% of activewear is made from petroleum byproducts like polyester and nylon. These fabrics shed microplastics directly into our water systems and press against your skin while your pores are wide open during a workout.
Microplastic Release (fibers / wash)
Source: Industry aggregated data (est.)
The Awakening is Happening
We aren't the only ones asking questions. Search volume for non-toxic textiles is exploding. Here are the top concerns driving consumers to clean alternatives.
Top Rising Search Terms
- 1.sustainable activewear brands22,000
- 2.acne from pillowcase18,000
- 3.best non toxic activewear15,000
- 4.plastic free bedding14,500
- 5.pfas in leggings12,000
- 6.organic cotton yoga pants11,000
- 7.dangers of microfiber sheets10,200
- 8.polyester allergy symptoms9,500
- 9.bpa in sports bras8,900
- 10.microplastics in lungs8,200
- 11.tencel vs polyester7,200
- 12.is nylon safe for skin6,700
- 13.hormone disruptors in clothes6,100
- 14.recycled polyester toxicity5,400
- 15.100% merino wool leggings4,500
Consumer Concern Landscape (relative volume)
Synthetic vs. Natural
Why do we ban polyester? It's not just about the planet; it's about performance. Natural fibers like Merino Wool and Tencel manage moisture effectively, whereas plastics trap bacteria and need chemical finishes to “wick” sweat.
Comparing: Breathability, Moisture Wicking, Odor Resistance, Sustainability & Skin Safety.
The Undo Machine
Select a common toxic item to see the ONDU-approved clean swap.
Polyester Leggings
Traps sweat, breeds bacteria, sheds microplastics.
Tencel / Merino Leggings
Naturally wicks sweat, antibacterial, breathable, zero plastic shedding.
Try: Reprise or IcebreakerWhat we curate
Every product is vetted for natural fabrics. No polyester. No nylon. No plastic on your skin.
32+
ONDU Move
Activewear that puts your skin first. Tencel, merino, organic cotton, hemp.
Explore15+
ONDU Sleep
Your pillowcase touches your face for 8 hours. Mulberry silk, organic cotton, linen.
ExploreComing soon
ONDU Beauty
What you put on your skin matters. Natural skincare, coming soon.
Notify mehow toxic is your activewear?
The Label Decoder
Enter the fabric composition from your activewear label. We will tell you exactly what is touching your skin, and whether you should worry.
Decode your labelThe Club
Weekly fabric science, brand investigations, and clean swaps. Opening to 500 founding members.
Hand-picked
Editor's picks
BasicsLYOLYTE G-String - Powder Pink
Stays put with a no-turn-back elastic for comfort and a smooth feel. Soft elastic waistband lies flat against the skin. Flat elastic edging around the leg opening prevents riding up or cutting in. Single layer ribbed gusset adds comfort. Sleek, seamless, and smooth finish, allowing freedom of movement. Fine, light knit construction for breathability and a lightweight feel. This style runs small, size up for a more comfortable fit.
Lounge & SleepSet Giftbox - Vegan Silk Long Sleeve Sleep Shirt & Wide Leg Sleep Pants - Pearl
Give the gift of comfort with our Giftbox - Vegan Silk Short Sleep Shirt & Wide Leg Sleep Pant Available in two new colourways, Pearl and Garnet Premium fabric and design, crafted entirely with organically grown bamboo viscose Ideal year-round for slow mornings, and lazy evenings
BasicsSeamfree Crop Bra - Black
Easy pull-on style. Wireless comfort, no padding, and hook-free construction. Low-medium support, suitable for up to a D-cup. Non-adjustable, wide fabric straps for shoulder comfort. Four-way stretch for a flexible and comfy fit. Soft ribbing for added comfort and subtle detail. Seamfree design for zero fabric wastage and effortless fit. Please note that this product has recently undergone a name change and was formerly known as the Shaper Crop Bra.
BasicsPeriod & Leak Proof - Full Briefs - Light - Moderate - Black
Soft and wide, flat-ribbed waistband. High rise, full coverage for a comfortable fit. Cold machine washable for reusable period and leak care. Fast-absorbing leakproof technology for light to moderate protection. Three-layer protection keeps you fresh and dry. Designed for light to moderate period days, occasional light bladder leaks, and discharge. Absorbency: Up to 2 regular tampons, up to 2 regular pads, holds 10ml. Certified as 100% PFA-free.
BasicsBoyleg Briefs - Shell
Soft, flat-ribbed waistband for a comfortable fit. Mid-rise cut. Full coverage style that won't ride up. Design combines sporty style with all-day comfort. This design features a stitched seam at the back gusset to reduce friction for a smoother, more comfortable feel.
BasicsClassic Bikini - White
Soft, flat-ribbed waistband for gentle support. Mid-rise design for a comfortable fit. Moderate to full coverage for versatile wear. Classic yet simple cut, perfect for everyday wear. This design features a stitched seam at the back gusset to reduce friction for a smoother, more comfortable feel.
BasicsHipster Bikini - Shell
Soft, flat-ribbed waistband for gentle support. Low rise design that sits comfortably on the hips. Cheeky cut with backside coverage, ensuring it won't ride up. Accentuates your natural shape. Moderate coverage for a comfortable fit. Stitched seam at the back gusset reduces friction for a smoother, more comfortable feel.
BasicsClassic Bikini - Maple
Soft, flat-ribbed waistband for gentle support. Mid-rise design for a comfortable fit. Moderate to full coverage for versatile wear. Classic yet simple cut, perfect for everyday wear. This design features a stitched seam at the back gusset to reduce friction for a smoother, more comfortable feel.
the story behind the curation
We started ONDU because we were pissed off.
95% of activewear is made from plastic. The industry calls it “performance fabric.” We call it petroleum on your skin. ONDU is the filter between you and an industry that puts profit over your pores.
Read our story
Know Your Fabric
Not all “sustainable” fabrics are equal. Here's what actually matters.