Value Village ／ Food & living
This answer is a draft. It stays unpublished until legal review and source verification are complete.
Japanese kitchen knives are famous, and sharpening them is often assumed to be a job for experts. What it actually needs is regularity and a consistent angle. And sharpening is not only about performance: Japanese safety bodies regard it as a safety matter too.
NITE (the National Institute of Technology and Evaluation, Japan's product-safety body) was notified of 49 accidents involving children and kitchen goods over the ten years from FY2010 to FY2019: 4 deaths, 8 serious injuries and 21 minor injuries. The Consumer Affairs Agency has also published accident reports from medical institutions under the heading "Beware of injuries from knives and other blades in the kitchen".
A sharp blade cuts where you aim it, with little force. A blunt blade needs extra force, and when that force slips, it becomes an injury.
[Verify] The accident figures are based on NITE material dated 21 July 2020. Confirm against the original before publication.
Sharpness fades gradually. Touching up little and often is less work than restoring a badly dulled edge.
Keeping the same angle is generally described as the basic rule. If the angle wobbles, the edge becomes rounded.
The right method differs by steel and blade shape. Check the product label and the maker's instructions. Whetstones (砥石, toishi) are sold at home centres and 100-yen shops in Japan.
Some products are not dishwasher-safe. Check the label.
Shops offering a sharpening service (研ぎ, togi) exist all over Japan, including many knife shops and department stores. Handing it over is a valid option.
Keep blades out of children's reach. Some of the accidents counted above could be reduced by this one step alone.
Always follow the instructions for the tools you use, and handle blades with care.
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https://www.nite.go.jp/data/000112900.pdf
https://www.caa.go.jp/policies/policy/consumer_safety/child/project_001/mail/20221208/
https://www.cfa.go.jp/policies/child-safety-actions/handbook/content-6
⚠️ 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.
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