Daily wear and repeated washing gradually affect the condition of underwear, making it less supportive and potentially less comfortable over time.
According to Health Digest, citing Good Housekeeping, fabric slowly loses its elasticity while the fibres weaken through regular use and laundering.
As a result, underwear may no longer fit properly, increasing the likelihood of skin irritation. Health Digest also reports that health experts say worn fibres can become harder to clean thoroughly, even after washing.
Material and wear
How long underwear lasts also depends on how frequently it is worn.
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According to Health Digest, citing The Independent, underwear used every day or during exercise typically wears out faster than pairs that are only used occasionally.
Health Digest, citing London Gynaecology, reports that cotton underwear may be worth replacing after roughly 50 washes. Other signs of wear include holes, fading, pilling and a poor fit.
The outlet also cites Yahoo! Shopping, which notes that cotton is often a practical choice for everyday wear because it is generally more breathable than many synthetic fabrics.
When to replace it
Experts also suggest that bacteria, moisture and dead skin cells can remain trapped in older textile fibres, despite regular washing.
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For that reason, the general recommendation is to replace underwear every six to twelve months. Underwear worn frequently or used for sports may need to be replaced even sooner.
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