We are constantly reminded that not getting enough sleep is bad for our health, but recent studies suggest that sleeping too much could also pose risks. Research indicates that sleeping more than nine hours a night may be linked to a higher risk of death and various health problems, though experts caution that this does not necessarily mean oversleeping is the cause.
The Sleep Health Foundation recommends adults get seven to nine hours of sleep per night. While some people are naturally short sleepers and function well on less, most individuals experience negative effects from insufficient sleep, including reduced energy, mood disturbances, and increased stress. Long-term sleep deprivation is a major risk factor for cardiovascular disease, metabolic disorders, poor mental health, and even cancer.
A recent review of 79 studies found that people who slept more than nine hours a night had a 34% higher risk of dying during the study period compared to those who slept seven to eight hours. This echoes earlier research from 2018, which reported a 14% increased risk of death for long sleepers. Oversleeping has also been linked to depression, chronic pain, weight gain, and metabolic disorders.
However, experts stress that these findings show a correlation, not causation. People with chronic health conditions often sleep longer, possibly because their bodies need extra rest or due to medication side effects. Poor sleep quality and lifestyle factors like smoking and obesity may also contribute to both oversleeping and poor health. In other words, sleeping too much may be a symptom rather than a cause of health issues.
Individual sleep needs vary by age; teenagers, for example, typically require eight to ten hours. The key takeaway is that while both too little and too much sleep are associated with health risks, the reasons behind these associations are complex and not fully understood.
