Good to Know
The Materials We Wear: What Makes a Fashion Material Sustainable?
From polyester to cotton, leather to viscose — what are our clothes really made from, and how sustainable are they?
Is there really such a thing as a sustainable material?
When we talk about sustainable fashion, we often hear phrases like sustainable materials, eco-friendly fabrics and better fibres. But what actually makes a material sustainable?
The answer isn't quite as straightforward as you might think.
There isn't a single global authority that decides whether a fashion material can officially be called “sustainable”. Instead, environmental and sustainability claims sit alongside different laws, standards, certification schemes and methods of assessing environmental impact.
In the UK, for example, the Competition and Markets Authority (CMA) says environmental claims should be truthful, clear, substantiated and should consider the full life cycle of a product. Broad claims such as “sustainable” or “eco-friendly” can be misleading if they create an impression that isn't supported by evidence.
And that's important because no material is perfect.
A material might use less water but require more energy. Another might come from a renewable source but involve chemicals during production. One might be difficult to recycle but last for decades. Another might be biodegradable but not particularly durable.
The European Environment Agency takes a life-cycle approach to textiles, looking at impacts from raw materials and production through to use and end of life. Its research shows that textiles create significant pressures through land and water use, energy consumption, greenhouse gas emissions, chemicals and waste.
So perhaps rather than asking whether a material is simply sustainable or unsustainable, we should be asking a better question:
So, what actually makes a material sustainable?
There are several things worth considering.
- Where do the raw materials come from? Are they renewable, recycled, responsibly sourced or dependent on finite resources?
- How much water is used? Growing natural fibres and manufacturing textiles can require significant amounts of water.
- How much energy is needed? And what kind of energy is being used during production?
- What chemicals are involved? Textile manufacturing uses chemicals across a number of processes, while some materials and treatments can create additional environmental concerns.
- How long will the product last? This is perhaps one of the simplest questions we can ask. A well-made garment that is worn for years has a very different story from one that is quickly discarded.
- What happens when we're finished with it? Can it be repaired, reused, resold or recycled? Or does it become waste?
The EEA places particular emphasis on durability, repairability, reuse and recycling as part of a more circular textile system — and suggests that extending the useful life of products should be prioritised.
In other words, sustainability isn't simply about what something is made from.
It's about the whole life of the product.
The materials already in our wardrobes
Many of the materials we wear every day have both advantages and environmental challenges. Here's a snapshot of some of the most common.
| Material | Why we use it | The sustainability picture |
|---|---|---|
| Polyester | Strong, versatile, affordable and quick-drying | The world's most widely produced fibre. Most polyester is fossil-based, and synthetic textiles can contribute to microplastic pollution. Recycled polyester can reduce demand for virgin resources, but textile-to-textile recycling remains limited. |
| Cotton | Natural, breathable, comfortable and biodegradable | Natural doesn't automatically mean low-impact. Cotton production can involve significant land, water, fertiliser and pesticide use. Organic and certified approaches can address some of these concerns. |
| Acrylic | Lightweight, warm and inexpensive; often used as a wool alternative | A synthetic, fossil-based fibre with a higher climate impact than many natural fibres and challenges around recycling. |
| Nylon | Strong, lightweight and durable | Usually fossil-based and energy intensive to produce. Its durability can be a benefit, but its production has a significant environmental footprint. |
| Elastane | Adds stretch, comfort and shape retention | Usually blended with other fibres, which can make garments more difficult to recycle. |
| Viscose | Soft, lightweight and made from plant cellulose | Plant-based doesn't automatically mean low-impact. Traditional viscose production involved significant chemicals, although production methods have improved and responsibly sourced cellulose can reduce some impacts. |
| Lyocell | Soft, versatile and cellulose-based | A newer generation of cellulosic fibre. Production can recover and reuse much of the solvent, while responsibly sourced wood is important. |
| Leather | Durable, versatile and potentially extremely long-lasting | Livestock production has significant land-use impacts, while tanning can involve water and chemicals. Its durability is an important part of the wider picture. |
| Wool | Warm, renewable, breathable and durable | Animal-based fibres can have significant land-use impacts. Farming methods and sourcing make a difference to the overall picture. |
The figures behind this table also illustrate why the conversation is complicated. According to Textile Exchange's 2025 Materials Market Report, global fibre production reached around 132 million tonnes in 2024, with polyester accounting for 59% of global fibre production. Of that polyester, 88% was fossil-based.
The European Environment Agency also highlights that natural and synthetic fibres have different environmental profiles. For example, cotton can have significant impacts related to land and water use, while synthetic fibres such as nylon and acrylic are associated with fossil fuel use and energy-intensive production.
It's rarely as simple as good or bad
And this is where things get interesting.
Polyester is fossil-fuel based, but recycled polyester can make use of existing resources. Cotton is natural, but conventional production can have significant environmental impacts. Leather has obvious environmental concerns, but a well-made leather product that lasts for many years is a very different proposition from something that needs replacing regularly.
Even plant-based fibres aren't automatically sustainable.
The European Commission's Joint Research Centre explains that bio-based textiles can come from sources including wood, crops, algae, fungi, agricultural waste and even end-of-life textiles. But it also points out that natural fibres can have impacts associated with water, land, fertilisers and pesticides, while the production of semi-synthetic fibres such as viscose and lyocell involves its own processes and challenges.
So perhaps there isn't a single winner.
The material is only part of the story.
How it is produced, where its raw materials come from, how much water and energy are used, how long the finished product lasts and what happens when we're finished with it all matter.
So where does that leave us?
Perhaps the answer isn't to find one perfect material.
Instead, the future of sustainable fashion is likely to be about using materials in better ways — reducing our reliance on virgin resources, making greater use of recycled and renewable materials, improving production processes, designing products to last and making them easier to repair, reuse and recycle.
There are already interesting developments happening. The European Commission's Joint Research Centre identifies agricultural waste, fungi and end-of-life textiles as potential sources for future bio-based fibres, while the wider move towards circular design is looking at how products can be made for longer use, repair, reuse and recycling.
And as shoppers, we don't need to become textile scientists before buying a T-shirt.
We can't always know exactly how a fibre was produced, how much water was used or what will happen to it twenty years from now.
But we can become a little more curious.
We can pay attention to what brands tell us about their materials, look for credible certifications where they exist, consider quality and longevity, and be wary of broad environmental claims that aren't explained or supported.
Because sustainable fashion isn't about finding perfection.
It's about making better choices with the information we have.
And perhaps that's where the most exciting part begins.
The exciting thing about sustainable materials isn't that we have found one perfect replacement for everything. It's that we're beginning to rethink what a material can be in the first place.
From fungi and agricultural waste to recycled fibres and materials designed for disassembly, the future could look very different from the one we're used to.
And for us as consumers, that's something worth getting excited about — and asking questions about.