News

A recent study has found that Korean women tend to sleep less and experience poorer sleep quality at an earlier age compared to women in the United States and Europe. In particular, for middle-aged women, the key change in sleep patterns is not simply getting less sleep, but having difficulty maintaining sleep throughout the night.

A joint research team from Samsung Electronics and institutions in the United States and Canada analyzed sleep data collected from Galaxy Watch devices worn by 192,500 women aged 20 to 65 living in the U.S., Korea, Germany, France, and the U.K. The dataset included approximately 3.8 million nights of sleep records. The researchers focused on “Wake After Sleep Onset” (WASO), a key indicator of sleep quality that measures how long a person stays awake after initially falling asleep.

The results showed that WASO increased significantly around menopause. Compared to women aged 20–24, women aged 50–54 stayed awake an average of 5.4 minutes longer (15.3%), those aged 55–59 by 8.8 minutes (24.9%), and those aged 60–64 by 11.2 minutes (31.7%).

In contrast, total sleep duration decreased only slightly—by about 13 minutes in the early 50s and 17 minutes in the early 60s. The researchers concluded that, for middle-aged women, the more significant issue is not reduced sleep time but the inability to maintain continuous sleep.

Although men also experienced increased nighttime awakenings with age, the rise was more gradual than in women. Notably, women showed the most significant increase between ages 45–49 and 50–54, while men exhibited similar changes only around age 60. The researchers suggest that these differences are likely related to hormonal changes during menopause.

Clear differences were also observed across countries. Korean women slept an average of 27.1 minutes less than American women and had 24.7 minutes less actual sleep. The gap was even larger when compared to women in Germany, France, and the U.K.

Additionally, the decline in sleep quality began earlier in Korean women. While nighttime awakenings in U.S. and European women typically increased around age 50, Korean women began experiencing increases as early as their early 30s. By their mid-30s, their WASO levels were similar to those of Western women, and thereafter followed a comparable upward trend.

The research team suggested that factors such as long working hours, later bedtimes, social stress, and lifestyle patterns common in Asian countries may contribute to these differences.

Experts emphasize that sleep disturbances during menopause should not be dismissed as a natural part of aging. Such issues are associated not only with fatigue and irritability but also with decreased concentration, lower quality of life, reduced work productivity, and an increased risk of cardiovascular and metabolic diseases.

If frequent nighttime awakenings persist for several weeks, consulting a medical professional is recommended. Maintaining regular sleep habits, engaging in consistent exercise, and reducing caffeine and alcohol intake can also help improve sleep quality.

The researchers noted that this large-scale study, based on approximately 3.8 million nights of real-world sleep data, provides objective insights into sleep changes in middle-aged women. They added that wearable devices can be useful tools for tracking long-term sleep patterns and supporting personalized sleep management and medical consultations.

The findings were recently published in the international academic journal Sleep.

Source: 헬스조선 (https://health.chosun.com/site/data/html_dir/2026/08/03/2026080302041.html)