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Plain warm water (sayu)
A listing is not a recommendation.
Origin: Japan and China · Tradition: East Asian food-based yojo · Food & herbs
What it is
The custom of drinking warm water with nothing added. It is described as waking the stomach and intestines in the morning, and warming the body from the inside.
A short introduction (not a treatment instruction)
- Drink a comfortable amount, slowly, of water that has been boiled and then slightly cooled.
- Do not gulp boiling water.
- If you have a condition with a fluid limit, follow that advice.
Symptoms or aims often mentioned with this practice
- Constipation or digestion
- Feeling cold easily
- Tiredness
Research notes (this is not a promise of effect)
D: Traditional use only. This review did not find enough clinical research on the practice itself
The sources were not confirmed in this review.
As part of adequate fluid intake it can be reasonable, but high-quality research showing that plain warm water is better than room-temperature water or other drinks was not found.
Safety notes
Burns (mouth and oesophagus). In heart failure or kidney disease, take care with the volume of fluid.
If you are unsure, or if you have a health condition, are pregnant, or take medicine, consult a qualified professional.
Situations in which this is better avoided
- A condition with a fluid limit (a physician’s advice comes first)