Every major fashion brand is shouting about recycled polyester like it is the second coming of sustainability. It is not. It is the same plastic, doing the same damage, wrapped in better marketing. Let's pull the thread.
Recycled Polyester Is Still Plastic
Here is the part that brands conveniently leave out of the press release: recycled polyester and virgin polyester are chemically identical. Same polymer. Same molecular structure. Same polyethylene terephthalate. The "recycled" part describes where the raw material came from (usually old PET bottles), not what the fabric does once it exists.
And what it does is exactly what virgin polyester does. It traps heat. It holds odour. It does not biodegrade. It will sit in a landfill for 200+ years, slowly fragmenting into smaller and smaller pieces of plastic that leach into soil and groundwater.
Most critically, it sheds microplastics. Every wash cycle sends hundreds of thousands of microscopic plastic fibres through your washing machine drain, past water treatment filters, and into rivers, oceans, and eventually your drinking water. The "recycled" label does not change the physics of plastic fibre fragmentation. Not even slightly.
Calling recycled polyester sustainable is like calling a recycled cigarette healthy. The origin story changed. The product did not.
The Numbers Brands Don't Want You to See
If recycled polyester performed identically to virgin polyester on microplastic shedding, that would be bad enough. But research from the Changing Markets Foundation in 2025 revealed something worse: recycled polyester can actually shed more microplastics than virgin polyester.
Why? The recycling process introduces structural irregularities into the fibre. PET bottles were engineered to hold liquid, not to be spun into thread. When you mechanically recycle them into textile fibres, the resulting filaments tend to be less uniform, with more surface defects and weaker bonding. Under the mechanical stress of a washing machine, these imperfections become fracture points. More fractures, more fibre fragments, more microplastics in your water.
Let that sink in. The material brands market as their environmental achievement is, by some measures, actively worse at the single biggest environmental problem polyester causes.
This is not a fringe finding. Multiple peer-reviewed studies have shown that mechanically recycled polyester textiles release equal or greater quantities of microfibres compared to virgin equivalents. The industry knows this. They fund the studies. They just do not put the results in the Instagram carousel.
The carbon footprint argument -- that recycled polyester uses less energy to produce -- has some validity. But it is a sleight of hand. Brands highlight the one metric where recycled polyester looks better while ignoring microplastic shedding, end-of-life disposal, and the destruction of bottle-to-bottle recycling infrastructure. Cherry-picking your sustainability data is not transparency. It is marketing.
It Breaks the Bottle Recycling Loop
This one is almost comically self-defeating. PET plastic bottles have one of the most functional recycling loops in existence. A bottle can be recycled back into a bottle, which can be recycled back into a bottle again. It is not perfect, but it is a genuine circular system that actually works at scale.
When fashion brands divert those PET bottles into clothing, they break that loop permanently. A polyester shirt cannot be recycled back into a bottle. In most cases, it cannot be recycled into anything at all. The blending of fibre types (polyester with elastane, with cotton, with nylon) makes textile-to-textile recycling economically and technically unviable for the vast majority of garments.
So the trajectory looks like this:
- PET bottle gets collected for recycling
- Fashion brand buys it and turns it into a t-shirt
- T-shirt sheds microplastics for 20 washes
- T-shirt goes to landfill because it cannot be recycled
- The bottle recycling system loses feedstock and has to use more virgin plastic
The bottle had a future. The fashion brand stole it, wore it for a season, and threw it away. And then put "made from recycled materials" on the label.
This is not circularity. This is a one-way ticket to landfill dressed up as progress.
Which Brands Push Recycled Polyester Hardest?
If recycled polyester is the green fig leaf of the fashion industry, some brands are wearing it more aggressively than others.
| Brand | Recycled Polyester Target | The Reality |
|---|---|---|
| H&M | 94% recycled polyester (of total polyester used) | H&M has made recycled polyester the centrepiece of its sustainability narrative. But the total amount of polyester in their products has not meaningfully decreased. They are using the same amount of plastic -- just from a different bin. |
| Adidas | 99% recycled polyester (across all products) | Adidas claims nearly all their polyester is now recycled. Impressive headline. But their Parley ocean plastic line and recycled polyester ranges still shed microplastics with every wear and wash. The shoe is still plastic. |
| Nike | Major recycled polyester push across Flyknit and Move to Zero lines | Nike has turned recycled polyester into a premium branding play. You pay more for the privilege of wearing plastic with a better origin story. The microplastic shedding does not care about your origin story. |
| Zara | Growing recycled polyester under Join Life / sustainability commitments | Zara's parent company Inditex has set targets for recycled and "preferred" fibres. But Zara's core range remains heavily synthetic, and the Join Life label applies to a fraction of their output. |
Notice the pattern. Not a single one of these brands is committing to using less polyester. They are committing to using recycled polyester -- which lets them maintain synthetic volumes, synthetic margins, and synthetic price points while claiming sustainability credit.
Swapping the source of your plastic is not a sustainability strategy. Reducing your dependence on plastic is. No major fast fashion brand is doing the second one.
What Would Actually Be Sustainable?
If brands genuinely wanted to reduce their environmental impact, recycled polyester would not be the headline. Here is what would:
1. Reduce synthetic fibre use entirely
The goal should not be "better plastic." It should be "less plastic." Every percentage point of polyester replaced with a natural fibre is a percentage point fewer microplastics entering waterways. This costs more. That is the point. Sustainability that does not affect the business model is not sustainability -- it is PR.
2. Prioritise natural fibres
Cotton, linen, hemp, wool. These fibres have clothed humans for millennia. They biodegrade. They do not shed plastic. They breathe. Yes, cotton has water-use issues and wool has animal welfare considerations. These are real problems worth solving. But they are problems within a fundamentally natural system, not problems caused by wrapping humans in petroleum.
3. Design for circularity -- real circularity
A garment designed for circularity would use mono-materials (no blends), avoid finishes and coatings that prevent recycling, and be constructed for disassembly. Almost no fast fashion garment meets any of these criteria. "Recycled polyester" blended with 5% elastane is not circular. It is a composite material that will end up in landfill.
4. Produce less
The most sustainable garment is the one that was never made. Overproduction is the engine of fast fashion, and no amount of recycled polyester offsets the damage of producing 100 billion garments a year. Brands that are genuinely sustainable produce less, charge more, and make things that last. That is incompatible with the fast fashion business model, which is why fast fashion will never be sustainable -- only less unsustainable.
How to See Through the Marketing
The fashion industry spends billions convincing you that the right purchase can save the planet. It cannot. But you can at least make informed decisions instead of manipulated ones.
That is why we built Fibr. Our free Chrome extension shows you the actual fabric composition of every product while you browse Zara, H&M, and Mango -- right on the product image, before you click, before you buy, before the marketing has a chance to work.
A green badge means natural fibres. A red badge means synthetic -- whether that synthetic is virgin polyester, recycled polyester, or any other plastic derivative. Because from a microplastic perspective, from a biodegradability perspective, and from a "what is actually touching your skin" perspective, the difference is negligible.
Fibr does not tell you what to buy. It tells you what things are actually made of. In an industry built on vague language and selective data, that is radical enough.