Value Village ／ Clothing
This answer is a draft. It stays unpublished until legal review and source verification are complete.
"Never wash your jeans" is advice that has circulated for years in denim-enthusiast communities abroad. In Japan the starting point is different: every garment sold here carries a standardised care label, and a law (the Household Goods Quality Labelling Act) requires it. This article explains what those labels tell you about denim, and where the popular advice goes wrong.
| Item | Guide | Basis |
|---|---|---|
| Wash-water temperature | At or below the number on the label (usually 30–40°C / 86–104°F) | Wash-tub symbol, JIS L0001 |
| Wash inside out | Reduces friction on the outer surface | A common way of limiting friction-related fading |
| Drying | Line-dry in the shade (symbol: a square with a vertical line inside and a diagonal stroke in the top-left corner) | Drying symbols, JIS L0001 |
| How often | When sweat or skin oils have built up | Hygiene; fibres left unwashed for long periods tend to degrade |
[Verify] Check the number of symbols and the dates on the Consumer Affairs Agency's "Care labelling" page, and the labelling obligation on its "Household Goods Quality Labelling Act" page.
Sweat and skin oils weaken fibres. Not washing can itself damage the fabric. There are ways to wash less often, but "never" is not something we recommend on hygiene grounds.
This idea spread overseas, but we could find no official evidence that bacteria die at household-freezer temperatures (around −18°C). The smell is only masked for a while.
The main causes of fading are the nature of the dye, friction and heat. In a machine, turning the jeans inside out, using a laundry net, cold water and a gentle cycle gets you close to hand-washing conditions. If the label shows a machine-wash symbol, a machine is fine.
If wet denim lies against other garments, colour can transfer at any wash, not only the first. Be especially careful with white clothing, synthetic-leather sofas and bags.
High heat damages the fibres. That is all the more true if the label shows "do not tumble dry" (a circle inside a square, crossed out). We do not recommend the dryer as a way of adjusting size.
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https://www.caa.go.jp/policies/policy/representation/household_goods/guide/wash_02.html
https://www.caa.go.jp/policies/policy/representation/household_goods/guide/fiber/
https://www.gov-online.go.jp/useful/article/201611/1.html
⚠️ Editorial note: the source URLs above were identified by search. Our working environment cannot reach go.jp domains, so the contents have not been checked against the text. Verify every source before publication and record who checked it and when.
What we share here are ideas and everyday practices passed down among people living in Japan, together with general information drawn from public sources. They are not official recommendations, and they are not professional instruction. Practices vary between households and regions.
This is general information. Results vary from person to person and depend on your own conditions and surroundings.
Please decide for yourself, using your own judgement, whether any of this suits your situation. We cannot accept responsibility for any damage, loss or injury arising from following this article.
Follow the care label and the maker's instructions for any garment, shoe or bag. For expensive or sentimental items, ask a specialist cleaner or repairer.
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