Sleeping Too Much Can Also Harm Health: The Risks to Watch Out For

Sleep deprivation is usually linked to a range of health problems, from difficulties concentrating to a weakened immune system. But what about sleeping too long? For some people, sleeping more than eight hours may feel like a luxury. However, experts warn that oversleeping can also have negative effects, especially if it occurs regularly and disrupts daily activities.

‘Though someone regularly sleeps more than nine or ten hours and still feels tired during the day, they may be experiencing oversleeping,’ explained Rees, as reported by Real Simple, on Thursday, 5 March 2026.

He added that long sleep duration become problematic only if it interferes with the ability to carry out daily functions and complete activities as usual.

According to the National Sleep Foundation, adults aged 18–64 typically require seven to nine hours of sleep per night. If someone consistently sleeps more than ten hours every day, this condition is often referred to as long sleeping. Oversleeping does not always indicate a serious disorder. In some cases, this occurs only occasionally.

‘Oversleeping can also occur as a side effect of certain medications, or when we are not well or are in a recovery period,’ said Reed. For example, after a very tiring week at work or after illness, the body can repay a sleep debt with longer sleep than usual.

However, if it lasts in the long term, oversleeping could be a sign of an underlying health condition. Reed explains that chronic oversleeping can be a symptom of disorders such as sleep apnoea, delayed sleep phase syndrome, or hypersomnia. According to the National Institutes of Health, hypersomnia is characterised by excessive daytime sleepiness and a need for sleep that is not easily controlled, with long naps that are not refreshing.