Value Village ／ Health
This answer is a draft. It stays unpublished until legal review and source verification are complete.
Herbal teas are widely drunk in Japan as "caffeine-free and gentle on the body". But in Japan a herb falls into one of three legal categories: food, medicine, or a food with function claims / FOSHU (Japanese categories for notified or approved health claims). The category sets a line on what health claims can be made. This article sorts that out, including the cautions for pregnancy and for people taking medication.
| Category | Examples | What can be said |
|---|---|---|
| Food (herbal tea) | Chamomile, rooibos, peppermint, rosehip | No health claims allowed. Only mood-setting phrases such as "for your relaxing moment" |
| Medicine (crude drugs, 生薬) | Dokudami tea (products approved as a crude drug), senna, kanzō (liquorice root) | The approved indication. Senna is a medicinal ingredient and cannot be used in food (the stem is an exception allowed in food) |
| Foods with Function Claims / FOSHU | Only products that have been notified or approved | The function within the scope of the notification |
FOSHU (トクホ) is Japan's approved "Food for Specified Health Uses" scheme; Foods with Function Claims (機能性表示食品) are notified to the Consumer Affairs Agency by the maker.
| Herb | Caution |
|---|---|
| St John's wort | Weakens the effect of many medicines (the pill, antidepressants, immunosuppressants, anti-HIV drugs, etc.). The Ministry of Health, Labour and Welfare (MHLW) issued a warning in 2000 |
| Liquorice (甘草, kanzō) | In large amounts or over a long period, raised blood pressure and low potassium. Caution for people with high blood pressure or on medication |
| Chamomile | People with an allergy to the daisy family (ragweed, etc.) may react. Some sources say avoid large amounts in pregnancy |
| Hibiscus, rosehip | Strongly acidic, with reports of irritation to teeth and stomach and effects on blood pressure |
| Mint | Can make gastro-oesophageal reflux worse |
| Pregnancy in general | Much guidance says avoid, or take only small amounts of, raspberry leaf, jasmine, sage, lemongrass and others. Check with your obstetrician |
[Verify] Check the St John's wort caution against the MHLW notice (May 2000) and each herb's cautions against the National Institute of Health and Nutrition database.
St John's wort weakens the effect of many medicines, and liquorice affects blood pressure. If you take medication, are pregnant or have a chronic condition, check with a doctor or pharmacist.
Only the caffeine is missing. The herb's own compounds act on the body, which is exactly why interactions exist.
Herbal teas sold as food cannot carry health claims (Health Promotion Act; Act against Unjustifiable Premiums and Misleading Representations). Stating flatly that it "relaxes" or "helps you sleep" is a problem.
Some herbs should be avoided. Even if a product says "OK during pregnancy", check with your obstetrician. Rooibos and barley tea (麦茶, mugicha) are generally described as unproblematic, but keep quantities sensible.
The stronger and longer you drink it, the more likely both the effects and the interactions. Around 1–3 cups a day; stop if you notice a change in how you feel.
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https://www.mhlw.go.jp/www1/houdou/1205/h0510-1_15.html
https://hfnet.nibiohn.go.jp/
https://www.caa.go.jp/policies/policy/food_labeling/health_promotion/
⚠️ 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.
This article is not meant to diagnose or manage any specific medical condition. If you are worried about your health, see a doctor rather than relying on your own judgement.
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