While some materials are great at wicking away moisture and neutralizing odour, others seem to trap smells and make them worse over time. Whether you’re trying to avoid gym clothes that turn into stink bombs or everyday wear that needs constant washing, here’s a rundown of the smelliest fabric—and why they’re so notorious.
1. Polyester
Polyester is hands-down one of the worst fabric offenders when it comes to odour retention. While it’s a favourite for activewear thanks to its moisture-wicking properties, the downside is that it doesn’t breathe well. Sweat gets trapped between your skin and the fabric, and the synthetic fibres actually encourage the growth of odour-causing bacteria.
Even after washing, the smell can linger. That’s because the structure of polyester fibres is hydrophobic (repels water), which makes it harder for detergent to fully penetrate and clean out the bacteria and oils that cause smells.
2. Nylon
Nylon, like polyester, is a synthetic fabric with moisture-wicking properties, often used in athletic wear and underwear. But it shares a similar issue: it’s not great at letting your skin breathe, which creates a warm, damp environment—perfect for bacteria.
While nylon doesn’t trap smells quite as stubbornly as polyester, it still ranks high on the odour scale. If you work up a sweat, you’ll likely notice nylon clothes holding onto that odour longer than natural fibres.
3. Acrylic
Acrylic is a synthetic material often used in sweaters and knitwear as a cheaper alternative to wool. Unfortunately, it’s another fabric that doesn’t breathe well.
Acrylic tends to trap body heat and moisture, which creates a breeding ground for odor-causing bacteria. It’s also prone to holding on to smoke, perfume, and environmental smells.
4. Rayon (and Other Semi-Synthetics)
Rayon, viscose, and modal are all semi-synthetic fabrics made from natural sources (like wood pulp) but processed heavily with chemicals. While they often feel soft and luxurious, they can absorb sweat and smells like a sponge—and not let go.
They don’t dry quickly, and when damp, they tend to get musty. If you’ve ever noticed a mildewy smell in your clothes after a humid day, rayon might be the culprit.
5. Cheap Blends
Low-quality fabric blends (especially those with high percentages of polyester or acrylic) often smell worse than pure fabrics. These are commonly found in fast fashion where cost trumps quality. They may be labeled as “breathable,” but don’t be fooled—many trap sweat and smells more than they let air in.