We often hear about the real dangers of getting too little sleep but on the other end of the spectrum. Sleeping too much also appears to have some risks. Sleep is a rapidly growing field of research. We are learning more all the time about how rest affects the body and mind. It’s known that sleep is a time when the body repairs and restores itself. Getting too little rest can lead to a whole host of health problems.
So, more sleep must be better right? Not so fast, say some researchers. More evidence is showing that spending an excess amount of time in bed is also linked with health hazards. In some ways, oversleeping itself appears to directly influence certain risk factors. In other cases, it may be a symptom of other medical conditions.
Are You Sleeping Too Much?
First, let’s address what oversleeping means. The gold standard of normal has long been considered eight hours, and it’s a good median benchmark. Recent reviews of current research from the experts at the National Sleep Foundation broaden the spectrum a little. They say that somewhere in the range of seven to nine hours is normal and healthy for most adults between 18 and 64 years of age.
Some say closer to seven hours could be even better, such as Arizona State University professor Shawn Youngstedt, who told the Wall Street Journal, “The lowest mortality and morbidity is with seven hours.” Other researchers have also linked seven hours of rest with things like longevity and better brain health.
The “right” amount of sleep proves somewhat individual. As some people will feel great on seven hours and others may need a little longer. However, in most studies and for most experts, over nine hours is considered an excessive or long amount of sleep for adults.
The Health Impact of Oversleeping
Seeking to find the sleep “sweet spot” for optimal health, researchers have been busy recently looking at how different habits connect with physical and mental well-being. Several trends have emerged linking oversleeping with higher rates of mortality and disease as well as things like depression.
Some of the negative impacts of oversleeping on health are as follows:
Increased Weight Gain
Researchers found links between weight gain and sleep. Short and long sleepers both gained more weight than normal sleepers. Over the six year period (1.98 kg and 1.58 kg), and were more likely to experience a significant weight gain. People sleeping over nine hours were 21% more likely than normal sleepers to become obese.
Higher Heart Disease Risk
Using information from the large National Health and Nutrition Examination Survey (NAHNES), researchers linked both short and long sleep with higher risk of coronary heart disease and stroke. The study found that people sleeping more than eight hours per night were twice as likely to have angina (chest pain caused by reduced blood flow) and 10% more likely to have coronary heart disease.
Higher All-Cause Mortality Risk
In addition to (and perhaps as a result of) all of the other associated health issues like obesity, heart disease and stroke, longer-than-normal sleeping is also linked with higher risk of death in general.
Impaired Glucose Tolerance
Glucose tolerance refers to the body’s ability to process sugars, and impaired glucose tolerance is a associated with insulin resistance and is a risk factor for type 2 diabetes and heart disease.