What your clothes are actually made of, and why it matters more than you think

Conventional cotton is one of the most chemically intensive crops on earth. It covers 2.5% of the world's agricultural land but accounts for 16% of all insecticides sold globally. Organic cotton eliminates synthetic pesticides and fertilisers entirely, which means healthier soil, safer working conditions for farmers, and far less chemical runoff into local water supplies.

The honest caveat: organic cotton still uses significant water to grow, and its yields per acre are lower than conventional cotton, meaning more land is needed to produce the same amount of fabric. It's genuinely better, just not a silver bullet. The most sustainable way to wear cotton is in recycled form, made from post-consumer and post-industrial waste, which uses dramatically less water and energy than growing new fibre from scratch.

Hemp is arguably the most environmentally impressive textile fibre that exists at commercial scale. It grows fast, reaching full height in 3 to 4 months, requires minimal water, naturally resists pests without pesticides, and actively improves soil health through a process called phytoremediation, which removes toxins and replenishes nutrients. It absorbs more CO₂ from the atmosphere than most trees per hectare. It is genuinely carbon-negative.

The fabric itself is durable and breathable, naturally antibacterial, UV-resistant, and it softens with every wash without degrading. The initial feel can be coarser than cotton, which puts some shoppers off, but well-processed hemp is soft, versatile, and will outlast almost any other fabric you own. Patagonia has been a notable champion of hemp, partnering with producers to bring domestic cultivation back to the US.

Linen comes from the flax plant, which requires no irrigation, no fertilisers, and no pesticides to grow well, particularly in European climates. France, Belgium, and the Netherlands produce the gold standard of linen. The entire flax plant is usable with minimal waste: the seeds go into food production, the oil into paints and varnishes, and the fibres into fabric. It is one of the most zero-waste crops in agriculture.

As a fabric, linen is breathable, moisture-wicking, naturally anti-bacterial, and only gets softer and more beautiful with washing and age. Its one limitation is that it wrinkles easily, which most linen devotees will tell you is part of its charm rather than a flaw.

TENCEL is a brand name owned by Austrian company Lenzing for their lyocell and modal fibres made from sustainably sourced wood pulp, primarily beech trees and eucalyptus. What makes it exceptional is the production process: a closed-loop system that recycles over 99% of the water and non-toxic solvents used. This means virtually no chemical waste enters the environment, which is almost unheard of in textile manufacturing.

The fabric itself feels silky, drapes beautifully, is naturally moisture-wicking and temperature-regulating, and is significantly softer than cotton at equivalent weights. It uses roughly 50% less water and emits less carbon than conventional rayon or cotton during production. It is certified biodegradable and compostable. If you're looking for a performance fabric that doesn't sacrifice sustainability, TENCEL is the current benchmark.

Bamboo as a plant is genuinely remarkable. It grows faster than almost any other plant on earth, requires no pesticides, minimal water, and absorbs enormous amounts of CO₂. So far, so good. The problem is that turning bamboo into soft, wearable fabric requires processing, and there are two very different ways to do it.

The most common method, used to produce what most brands sell as "bamboo fabric," is the viscose or rayon process. This involves dissolving bamboo pulp in harsh chemical solvents, many of which are toxic and environmentally damaging when not properly managed. The resulting fabric retains almost none of the original plant's sustainability credentials. The eco-friendly bamboo plant has been transformed into something chemically similar to conventional viscose.

The better option is bamboo lyocell, produced using the same closed-loop process as TENCEL, where solvents are recovered and reused. This genuinely carries the sustainability of the source plant through to the finished fabric. Look specifically for bamboo lyocell or bamboo linen (mechanically processed). If a label just says "bamboo" without specifying the process, assume it's viscose.

Recycled polyester, often called rPET, is made from post-consumer plastic bottles and old polyester garments, keeping plastic out of landfill and oceans while reducing the need for virgin petroleum. It uses up to 59% less energy and cuts carbon emissions by up to 32% compared to making new polyester from scratch. By 2023, 13% of all polyester globally came from recycled sources, up from 8% in 2008.

The significant ongoing problem is microplastics. Every time synthetic fabrics are washed, they shed tiny plastic fibres that pass through washing machine filters, into wastewater, and eventually into oceans and food chains. Recycled polyester sheds microplastics at the same rate as virgin polyester. Using a washing bag like a Guppyfriend or fitting a microplastic filter to your washing machine reduces this, but doesn't eliminate it. For performance and activewear where natural fibres genuinely don't function as well, rPET is the best available option. For everyday clothing, natural fibres are preferable.

Wool is renewable, biodegradable, naturally temperature-regulating, moisture-wicking, fire-resistant, and extraordinarily durable. A quality wool jumper can last decades with proper care. From a pure materials standpoint, these are exceptional credentials. The complications lie in how and where it's produced.

Industrial wool production can involve poor animal welfare practices including mulesing, a painful procedure performed on merino sheep without anaesthesia. Large-scale sheep farming also has significant land use and methane emission implications. The solution is to look for certified wool, particularly the Responsible Wool Standard (RWS), which covers animal welfare and land management, or ZQ Merino, which is one of the most rigorous welfare certifications available. Certified wool is genuinely a good choice. Uncertified wool from unknown sources is a gamble.