Japan Health Ministry Recommends At Least 6 Hours of Sleep for Adults; Also Advises Lessening Caffeine Intake

The Yomiuri Shimbun

11:35 JST, January 14, 2024

Adults should sleep at least six hours per day, with lack of sleep causing different health risks for each age group, according to the latest edition of sleep guidelines compiled by the Health, Labor and Welfare Ministry.

The 2023 edition of “Sleep Guidelines for Health Promotion” — revised for the first time since 2014 — presents various recommended lengths of sleep by age group.

The guidelines advise adults to sleep six hours or more a day. Using their days off to try and make up for lack of sleep during the weekday can incur the risk of damaging their health, it also said. As well, the report recommended nine to 12 hours of sleep for elementary school students, and eight to 10 hours of sleep for junior and senior high school students. On the other hand, the elderly are cautioned to not spend more than eight hours in bed sleeping or taking naps for long hours as that increases the risk of death.

Sleep deprivation among children has been reported to lead to obesity, depression and poor academic performance, the report pointed out, and provided recommended amounts of sleep by age group in detail. For example, 11-14 hours for children age 1 to 2, and 10-13 hours for children age 3 to 5. The report also noted that children should not make it a habit to stay up late at night or sleep late in the morning.

Aerobic exercise, such as walking, and taking a bath one to two hours before going to bed will help people fall asleep better, according to the guidelines. Keeping the bedroom as dark as possible will also help people sleep well.

In addition, the report stated that daily caffeine consumption should be less than 400 milligrams, roughly equivalent to four cups of coffee, and people should refrain from eating just before going to bed.

Japanese people sleep an average of seven hours and 22 minutes a night, the shortest among 33 countries surveyed by the Organization for Economic Cooperation and Development in 2021. Since sleep deprivation increases the risk of cerebral and cardiovascular diseases and depression, the health ministry decided to provide a standard for sleep improvement.