The science behind wool’s odour resistance supports a ‘wear more, wash less’ approach, with research proving that the wool fibre naturally stays fresher for longer.
Why is wool naturally odour resistant? Wool textiles are naturally odour resistant and need less frequent washing, due to the wool fibre’s unique properties. Wool fibres can absorb large quantities of water vapour – twice as much as cotton and 30 times as much as polyester – to keep the skin drier and prevent the build-up of sweat, bacteria and unpleasant smells.
How Does Wool Naturally Resist Body Odour?
Why doesn’t wool retain body odour? The wool fibre absorbs moisture and locks away odours, preventing the build-up of sweat and bacteria that cause unpleasant smells. Made from a physical and chemical structure that helps to manage both moisture and odour, the wool fibre naturally absorbs sweat and holds odour molecules that keeps wool clothes fresher for longer between washes.
How it works
Wool is a hygroscopic fibre, meaning it readily absorbs moisture – up to 35% of its own weight – which keeps the skin surface drier and discourages bacterial growth.
Wool absorbs and locks away odour during wear. The high sulphur proteins in the matrix region found deep within the fibre can capture odour-causing molecules generated by sweat.
The odour molecules are held by the fibre until they are washed, minimising unwelcome smells and allowing wool garments to stay fresh for longer with fewer washes.
Does Wool Retain Less Odour Than Other Fabrics?
Wool fabrics retain less odour after wear compared to other natural or synthetic fibres, like cotton and polyester. Research shows that polyester fabrics retain higher levels of odour after wear, compared with wool fibres. A New Zealand study with 13 trained olfactory assessors found that wool fabrics retained 66% less body odour intensity than polyester and 28% less than cotton.
Research on Wool’s Odour Resistance
A recent study funded by Australian Wool Innovation and led by AgResearch in New Zealand in partnership with Consumption Research Norway (SIFO), investigated the odour retention and washing frequency of different fibre types. Using human volunteers, the study assessed how many days base-layer T-shirts, mid-layer hooded sweaters and socks made from Merino wool, cotton and polyester could be worn before laundering was required based on odour levels.
The results showed that polyester garments required washing after fewer days of wear when compared to wool and cotton. The study also evaluated the energy consumption associated with laundering these fibres. Merino wool proved to have the lowest energy consumption, with polyester using the most energy, followed by cotton. Merino wool used 76% less energy than polyester for mid-layer garments, 68% less for base-layer garments and 37% less for socks, making it a more energy-efficient option.
“The fact that wool clothes need less frequent washing not only reduces energy consumption, it also preserves the as-new look of the garment, enabling consumers to continue wearing it for longer.”
- Angus Ireland, Australian Wool Innovation Program Manager for Fibre Advocacy and Eco Credentials.
Wearing Wool is Proven to Reduce Body Odour
The odour sorption and emission characteristics of fabrics affect their functional performance, particularly for sportswear.
A study conducted by the Institute for Frontier Materials at Deakin University systematically evaluated the impact of wool in polyester/wool blends on body odour retention properties. It was found that wool had the highest odour sorption capacity among all the test fabrics.
Under high levels of body odour, where sorption plays a more important role, 100% wool showed higher sorption capacity than all the polyester/wool blends.