The Surprising Risks of Sleeping Too Much

In a world where so many of us are struggling to get enough sleep, the issue of sleeping too much might seem like a luxury problem.

It’s actually not. Like insufficient sleep, oversleeping is a sign of disordered sleep. It may be connected to a mental health issue, such as depression. It’s often a signal that a person is experiencing poor sleep quality, and it can be a sign of a clinical sleep disorder, including obstructive sleep apnea or narcolepsy.

Sleeping too much is linked with many of the same health risks as sleeping too little, including heart disease, metabolic problems such as diabetes and obesity, and cognitive issues including difficulty with memory. Similar to people who sleep too little, people who sleep too much have higher overall mortality risks.

We talk a lot about insufficient sleep, and the risks that a lack of sleep poses for physical health, mood, relationships, and performance. But oversleeping isn’t something to ignore.

Hypersomnia is the clinical term for excessive sleeping and excessive sleepiness during the day. Like its counterpart, insomnia, hypersomnia has several core symptoms:

• Sleeping for extended hours at night (typically well beyond the seven- to eight-hour norm).
• Difficulty waking up in the morning (including sleeping through an alarm).
• Trouble rising from bed and starting the day.
• Grogginess on and off or consistently throughout the day.
• Trouble concentrating.

What I’m not talking about here is the once-in-a-blue-moon night of extra sleep you might need after coming up unexpectedly short on sleep. That happens to everyone. If you’re making consistency a priority in your sleep routine, it shouldn’t happen often.

How much sleep is too much?

I've said it before: There is no single right amount of sleep that applies to everyone. Sleep needs are individual. They’re based on a number of factors:

Your individual genetics. Your genes influence both your circadian rhythms and your internal sleep drive, the two primary biological sleep systems

Your age. You may find you need seven hours of sleep in your 20s and eight hours — or six and a half — in your 50s or 60s.

Your activity level. Sleep is time for the body to recover from exertion. The more active you are, the more sleep you may need.

Your health. When coping with health issues, we very often need additional rest. That’s true for short-term illnesses, like colds and flu, as well as long-term or chronic conditions — everything from arthritis to cancer.

Your life circumstances. Stress and periods of change or upheaval can temporarily increase your need for sleep. (At the same time, these forces often make it difficult to sleep.) If stress is chronic, it can create a chronic sleep debt. And it’s not just negative or unwelcome life events that can drive up a need for sleep: Big life changes that are positive can demand more sleep, too!

All of this said, most of us, throughout our adult lifetimes, need somewhere in or near to seven-nine hours of sleep a night routinely. You might be a person who needs six or six and a half. But it’s unlikely that any but a very few of us can function and feel at our best on five hours of nightly sleep or less. This is similarly true at the other end of the range. Some people need nine hours of sleep a night. But if you’re regularly sleeping more than nine hours and still feeling tired and fatigued, that’s an indication that you’re oversleeping — and it’s time to take a look at what might be causing it.

Oversleeping and depression

Particularly among younger adults and teenagers, oversleeping can be a signal of depression. It can be tough to gauge teens’ sleep, because they typically have very different sleep patterns than we adults do. But excessive sleepiness and sleeping in teens and young adults can be a red flag. An estimated 40 percent or more of adults under 30 with depression experience hypersomnia.

Oversleeping is not only an issue among young people with depression. Among older adults, symptoms of insomnia may be more common. But many older adults also experience hypersomnia in connection with depression. Women, in particular, may be more likely to oversleep and feel excessively tired during the day if they are depressed.

It’s also important to remember that among people with depression, sleep difficulties often take shifting, variable forms. People with depression may experience symptoms of both insomnia and hypersomnia. A 2014 study investigated how often insomnia and hypersomnia occur together in adults with depression in the U.S. Scientists found that more than 27 percent have what’s known as “co-occurring” insomnia and hypersomnia. They also found some other striking, shared characteristics. People with depression who demonstrated both insomnia and hypersomnia had:

• More severe depression.
• Higher rates of suicide planning and suicide attempts.
• Higher rates of impulse control disorder.
• Greater likelihood of drug use disorder.

These people were also more likely to be receiving mental health treatment and more likely to be taking antidepressants.

Another study released just this year found that among people who’d received a diagnosis of major depression, slightly less than one-third had both insomnia and hypersomnia. These people were at two to three times greater risk for bipolar disorder, according to the study.

Because of the close, complicated ties between sleep, circadian rhythms, and depression, it makes sense that more severe depression might often go hand in hand with more intense, variable, and wide-ranging sleep problems — including a drive to sleep excessively. The cause and effect in these relationships is usually not clear: We don’t often know whether sleep problems including hypersomnia lead to depression, or are a result of depression — or some of both. What we do know is that these conditions frequently go together.

When oversleeping is a symptom of a sleep disorder

Sleep disorders don’t always make it harder to get enough sleep. They also interfere with sleep quality and sometimes trigger excessive sleepiness and oversleeping. Any sleep disorder or issue that creates sleep deprivation can lead to excessive daytime sleepiness and a tendency to oversleep, in order to compensate for that sleep deficit. But hypersomnia is closely linked to a few sleep disorders in particular:

Narcolepsy. Narcolepsy is a neurologically based sleep disorder where the brain lacks the ability to control sleep-wake cycles. People with narcolepsy experience excessive daytime tiredness and often strong and uncontrollable urges to sleep during the day. They often experience insomnia at night. Because their sleep is so disrupted, and they have difficulty sleeping well at night, people with narcolepsy may not get excessive total amounts of sleep. But their constant excessive sleepiness and drive to sleep during the day are a specific form of hypersomnia.

Restless Leg Syndrome (RLS). People with restless leg syndrome experience tingling, twitching, “creepy-crawly” feelings in the legs. These uncomfortable sensations bring about an often-urgent need to move the legs. The symptoms of RLS are most often felt when a person is lying still for a period of time and are frequently most intense at night. People with RLS commonly experience symptoms of insomnia — the unpleasant nighttime sensations in their legs make it very difficult to fall asleep and stay asleep. As a result, people suffering from RLS often cope with excessive daytime sleepiness and may oversleep, because they’re not getting the high-quality rest they need during their seven- or eight-hour nighttime window.

Obstructive sleep apnea. People with sleep apnea experience compromised breathing while they sleep. During sleep, the airway becomes either partially or completely blocked for a short amount of time. These episodes happen over and over again throughout the night, causing frequent awakenings (which the sleeper may or may not be aware of) and leading to a steep decline in sleep quality. There are serious health conditions associated with sleep apnea, including greater risks for cardiovascular disease, stroke, and diabetes.

Because sleep quality is so negatively affected by sleep apnea, people with OSA are often excessively sleepy during the day. They may also spend extended hours in bed, needing more time to sleep, because their sleep quality is so poor.

Idiopathic hypersomnia. Some people sleep excessively without a clear, identifiable cause. This is a sleep disorder known as idiopathic hypersomnia — idiopathic meaning "without a known cause." People with idiopathic hypersomnia sleep for extended periods of time at night and still feel very tired during the day.

Other causes of oversleeping:

Substance use disorders. Drug use and alcohol use can lead to disrupted circadian sleep-wake rhythms, declines in sleep quality, and can bring on a pattern of oversleeping and excessive daytime tiredness.

Medical conditions. There are a range of health conditions that can cause oversleeping and persistent, intrusive sleepiness during the day.

Neurological disorders, including Alzheimer’s disease, Parkinson’s disease, and multiple sclerosis, as well as brain injuries.

Epilepsy.

Being overweight or obese.

Certain genetic disorders and genetic predispositions can cause hypersomnia. People with a family history of hypersomnia are more likely to experience oversleeping and daytime tiredness.

A number of medications can cause hypersomnia, including:

• Sedatives
• Tranquilizers
• Antidepressants
• Anti-anxiety medications
• Antipsychotics
• Antihistamines
• Anticonvulsants

How to deal with an oversleeping issue

It’s important to talk with your doctor if you’re sleeping excessively or feeling very tired during the day regardless of how much you sleep. If you notice changes to your sleep patterns and sleep needs, including an uptick in your level of tiredness or the amount you’re sleeping, that’s information to share with your physician. When you identify the underlying cause, you and your doctor can work to address both that condition and your oversleeping.

Limit alcohol to improve your sleep quality and sleep patterns. Drinking too much, too frequently, and too close to bedtime can all disrupt circadian sleep-wake rhythms and undermine high-quality sleep, leading to a need to oversleep.

Avoid becoming sleep deprived and accruing a large sleep debt. Our bodies will seek the sleep they need. Going with too little sleep will put you in a situation where you’re periodically oversleeping to compensate. These irregular sleep patterns aren’t healthy for your body or your mind.

Consistency is the most important element of a strong, health-promoting sleep routine. Identify the right amount of sleep you need, and then set up a schedule that enables you to meet that need routinely. It can take a bit of trial and error to get the amount right. Use the broad guidelines I’ve discussed above, and pay close attention to how you think and feel throughout the day.

LinkedIn Image Credit: Zephyr_p/Shutterstock