# Heatstroke prevention and management in Japan > Live situation record from CLSTR: https://clstr.news/situations/heatstroke-prevention-and-management-in-japan > Updated: 2026-08-19T22:10:00.000Z. Sources: 2. Developments: 2. Medical experts in Japan are discussing heat acclimatization and the risks associated with common cooling methods during extreme heat. Dr. Yusuke Kato of the Japan Sauna Society suggests using saunas to help the body adapt to heat through gradual exposure. However, research indicates significant public unawareness regarding certain cooling tools. A survey of 1,110 adults in Japan revealed that 66.1% of respondents did not realize that using handheld fans in temperatures above 35°C can increase heatstroke risk by blowing hot air and accelerating dehydration. The survey also identified a trend of ‘heatstroke prevention poverty,’ where individuals attempt to save on electricity costs by purchasing cooling goods, only to find the total expenditure higher than using air conditioning. There are also concerns that elderly populations may be avoiding air conditioning to save money, which increases their vulnerability to heat-related illnesses. ## Timeline ### 2026-08-19: Heatstroke prevention: Sauna acclimatization and handheld fan risks Experts suggest sauna use for heat acclimatization, while warnings emerge regarding the risks of handheld fans in extreme heat and the financial pitfalls of avoiding air conditioning. 2 sources. https://clstr.news/cluster/heatstroke-prevention-sauna-acclimatization-and-handheld-fan-risks ### 2026-08-09: Health advisory warns against sudden cooling after sun exposure Medical experts warn that sudden exposure to strong fans or air conditioning after being in the sun can cause circulatory issues and facial nerve paralysis, especially in vulnerable populations. 5 sources. https://clstr.news/cluster/health-advisory-warns-against-sudden-cooling-after-sun-exposure --- Cite as: Heatstroke prevention and management in Japan. CLSTR, https://clstr.news/situations/heatstroke-prevention-and-management-in-japan