Oversleeping 9+ hours may be worse than too little sleep: Study finds
We all know that too little sleep can negatively impact our health, increasing the risk of heart disease, depression, and weakened immunity. But what about getting too much sleep? Emerging research suggests that sleeping more than nine hours a night may be more harmful than previously believed — possibly even riskier than sleeping too little.
Oversleeping has now been linked to a greater risk of early death and chronic conditions such as diabetes and depression. Rather than being a harmless habit, excessive sleep might be a sign of deeper underlying health issues.
Why Sleep Matters as Much as Diet and Exercise
Sleep is a cornerstone of good health — as essential as proper nutrition and regular physical activity. While you sleep, your body performs critical functions: it repairs tissues, builds muscle, regulates hormones, strengthens immunity, consolidates memory, and maintains emotional and cognitive balance.
According to the Sleep Health Foundation, adults should aim for 7 to 9 hours of sleep each night. While some people may function on slightly less, regularly getting under seven hours can lead to fatigue, irritability, poor focus, and reduced productivity.
Long-term sleep deprivation has been tied to severe health issues, including:
Heart attacks
Stroke
Type 2 diabetes
Depression and anxiety
Increased risk of early death
But research now indicates that consistently sleeping more than 9 hours may also carry these risks — and in some cases, more strongly than short sleep durations.
What This Means for You
If you're regularly sleeping more than nine hours and still feel tired, it may be worth consulting a doctor. Oversleeping could be a symptom of sleep disorders, mental health conditions, or chronic illness.
In the end, quality and consistency of sleep matter most. Strive for a healthy sleep routine, just as you would with diet and exercise. Balance is key — because when it comes to sleep, both too little and too much can be harmful.