Home — World self-care & traditional therapies — Heat & water

Foot bath (ashi-yu)

A listing is not a recommendation.

Origin: Japan · Tradition: Japanese folk care and onsen culture · Heat & water

What it is

A simple heat practice in which the feet, from the ankles down, are placed in warm water. It is often easier at home than a full bath, and has been used for cold feet, tiredness, and winding down before sleep.

A short introduction (not a treatment instruction)

Pour comfortably warm water (around 40°C as a rough guide) into a basin or a foot-bath vessel. The water should not feel scalding.
Keep the feet covered above the ankle for 10 to 20 minutes. Add warm water if it cools.
When the aim is sleep, it is often done about an hour before bed.
Dry the feet afterwards and put on socks so they do not cool quickly.

Symptoms or aims often mentioned with this practice

Cold or puffy feet
Feeling cold easily
Sleeplessness
Tiredness
Stress or unease

Research notes (this is not a promise of effect)

B: Randomised trials or systematic reviews exist, but reports are modest, the group studied is limited, or study quality is limited

Several systematic reviews and meta-analyses from 2024–2025 have reported improvements in older adults’ subjective sleep quality after a warm foot bath before bed. Evidence on objective sleep measures is still weak. This does not show a treatment effect on cardiovascular disease.

Sources

Safety notes

Water that is too hot can burn. This is especially risky for people with reduced sensation. Avoid long periods at high temperature.

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

Reduced sensation in the feet, for example from diabetic neuropathy (burn risk)
Severe vascular disease, untreated skin infection, or an open wound
Sudden swelling, or marked swelling on one side only (seek medical care first)