Is Too Much Sleep Bad for You?

Is too much sleep bad for you?

Check out this answer from Consensus:

Excessive sleep, defined as sleeping more than 10 hours per day, is associated with several health issues, including psychiatric disorders, higher BMI, impaired daily functioning, and poor sleep quality. Additionally, both insufficient and excessive sleep are linked to increased risks of metabolic and cardiovascular diseases, suggesting that maintaining a balanced sleep duration is crucial for overall health.

Sleep is a fundamental aspect of human health, influencing physical, mental, and emotional well-being. While insufficient sleep has been widely studied and linked to various health issues, the effects of excessive sleep are less understood. This synthesis aims to explore whether too much sleep is detrimental to health by analyzing findings from multiple research papers.

Key Insights

• Association with Psychiatric and Physical Health Issues:
  • Long sleepers (over 10 hours/day) are more likely to have psychiatric diseases and a higher body mass index (BMI)5 8.
  • Excessive sleep is linked to impaired daily functioning and distress due to excessive sleepiness8.
• Quality of Sleep and Cognitive Function:
  • Excessive sleep can lead to a deterioration in sleep quality and negatively impact cognitive function and mood7 9.
• Metabolic and Cardiovascular Risks:
  • Both short and long sleep durations are associated with increased risks of obesity, diabetes, and cardiovascular diseases2 5 6.
• General Health and Mortality:
  • A U-shaped relationship exists between sleep duration and morbidity/mortality, with both very short and very long sleep durations posing health risks5.

Is too much sleep bad for you?

Is too much sleep bad for you?

Alexandre Keller has answered Unlikely

An expert from Universidade Federal de São Paulo in Immunology

The scientific article pointed out several limitations of the study including the lack of long-term patterns of lifestyle behaviors and cause-specific mortality data. Also, as discussed by some of the colleagues, hours in the bed does not mean healthy sleep quality. Thus, the article posted in the dailymail is much more an over-interpretation of the scientific data than a critical reading of the scientific article.

Is too much sleep bad for you?

Jeremy Borniger has answered Unlikely

An expert from Stanford University in Sleep Research, Neurobiology

There seems to be a U-shaped relationship between amount of sleep and health, where too little and too much sleep is associated with poor health outcomes. For example.

While most research focuses on short or fragmented sleep, as this can cause inflammatory responses or changes in metabolism, research focusing on the long-sleep association has been sparse. This is due to the relatively nebulous nature of a potential mechanism….why would sleeping too long be associated with increased mortality?

An ultimate explanation is that sleeping too long prevents one from eating or having sex or evading predators…but this doesn’t explain the more day-to-day consequences of too much sleep. Perhaps the long sleep is merely an association with some underlying condition that is not controlled for in all these studies (like low grade inflammation which can promote sleep). Or it may depend on how sleep is measured between studies.

Some studies use polysomnography, but those are rare. Most use questionnaires or actigraphy which cannot actually measure sleep/wake states. A more useful measure might be ‘time in bed’ rather than actual sleep time. For instance, in this paper the association goes away when sleep is measured by sleep logs and actigraphy.

Is too much sleep bad for you?

Mark  Mahowald has answered Unlikely

An expert from University of Minnesota in Neurology, Sleep Research

There are two issues: 1) numerous studies have suggested reduced longevity in both long and short sleepers. This is a statistical correlation which does not establish causation. There are likely many factors involved, and the sleep duration may be an unrelated manifestation of some other variable. 2) sleep duration is determined by the phase of the underlying biological clock and the duration of prior wakefulness. Each individual’s sleep requirement is genetically determined. One cannot sleep unless there is a pressure to sleep (one cannot sleep in the absence of true physiological sleepiness) – therefore it is not possible to “sleep too much” – as the brain wakes up when satiated.

Is too much sleep bad for you?

Melody Ding has answered Likely

An expert from University of Sydney in Epidemiology, Health

I wish there were a choice of “not enough good evidence” because, in my view, the answer lies between “likely” and “unlikely”. Although there has been a “U-shape” association found between sleep duration and health outcomes (e.g., mortality), at this point, we do not have enough good evidence to say that too much sleep “causes” poor health and there is no convincing mechanism for that. The challenge in on-going epidemiological research is sufficiently controlling for confounding–people who sleep too much are different from those who sleep optimal amounts: long sleepers often have chronic conditions (physical or mental) and poorer health; they may also stay in bed longer because of their poor sleep quality. Therefore, there is a lot of alternative explanation for the association we currently observe.

From a behavioural point of view, we only have 24 hours in a day, and if one sleeps too much, it will undoubtedly take time away from other (and possibly constructive behaviours), such as physical activity. In this context, it is important to bear in mind that the original study was not set up to study sleep duration alone. Instead, it aimed at examining combinations of risk behaviours. The high-risk profile involved long sleep duration, physical inactivity and prolonged sitting time.

Is too much sleep bad for you?

James Ware has answered Unlikely

An expert from Eastern Virginia Medical School in Sleep Research

Sleep is homeostatic and adaptive with an expected range for most people of 6-9 hr. Each person has a sleep set point, which the body tries to maintain. Too little sleep results in sleepiness. Too much leads to more time awake at night.

For most adults, the set point is about 7.5 hours. However, one’s immediate sleep needs and therefore sleep time appropriately fluctuates in response to internal and external happenings. For example, after heavy exercise some sleep a bit more possibly due to inflammatory / soporific cytokines.

Fortunately, we can sleep less to complete tasks, e.g., hunting for food or completing a report. Too much sacrificing sleep for other task contributes to a sleep debt along with cognitive and physiological problems. Fluctuations in sleep can be due to the brain and muscles responding to the day’s activities, infection, noisy neighbors or even changes in the microbes of the gut.

Frequent perturbations or a lot of time spent outside of the normal physiological set point interfere with the functions of sleep and our circadian rhythms. Thus, chaotic sleep can impair most body functions including metabolic, cardiovascular, immune, and cognitive activity. It is not possible for a healthy person to “overdose” on sleep. The person will instead lie awake, usually uncomfortably, in bed or get up.

Sleeping too much is a strong warning sign of a problem and deserves discussion with a doctor. It is our canary in the coal mine. This recognition hopefully leads to changes that can forestall death!

Is too much sleep bad for you?

Kath Bernard has answered Likely

An expert from Bournemouth University in Endocrinology, Sleep Research

I agree, sleep has a direct and important impact on well-being. Sleep deprivation is argued to be a cause of psychosis and there is a U shape curve in terms of sleep and risk of type 2 diabetes and cardiovascular disease. Sleep quality is as important as sleep quantity.​ The key factor here I suspect is the combination of risk factors that collectively contribute to negative outcomes. Sleep, in itself, is one risk factor, however the researchers have identified that sedentary behaviour, lack of exercise and other life behaviours contribute to disease state. Addressing modifiable lifestyle behaviours, including sleep, to improve health and well-being is recommended by healthcare professionals and government policy.

Is too much sleep bad for you?

Craig Heller has answered Unlikely

An expert from Stanford University in Biology, Neurology

Sleep is homeostatically regulated, so you may spend too much time in bed, but that will not translate into more sleep than you need. However, sleeping an excessive amount may be an indication of something else that is wrong and is bad for you — eg. depression or an infection or some other illness. There is a condition called hypersomnia which as the name suggests is associated with more sleep than normal. But, the more sleep is not causing the hypersomnia, rather the factors (not known) producing hypersomnia are causing more sleep.

Is too much sleep bad for you?

Paul Shaw has answered Unlikely

An expert from Washington University in St. Louis in Neuroscience, Sleep Research

my answer is “no” despite evidence indicating that long-sleeping humans are at increased risk for all-cause mortality. My view is that long-sleeping humans are actually less efficient at sleeping and thus require more time to accomplish what most of us can do in 8 hours. Since the clock and social pressures prevent us from sleeping more, long-sleepers are likely sleep deprived.

Is too much sleep bad for you?

Vivien Abad has answered Unlikely

An expert from Stanford University in Psychology, Sleep Research

The Australian publication reports associations between mortality and sleep duration that have been known for some time.

Mortality rates are higher for men who sleep < 4 hours/night (2.8 times as likely to die within 6 years as the 7-8 hour sleepers while) and those who slept >10 hours/night were 1.8x as likely to die; in women, the counterparts are 1.5 and 1.8x, respectively. (Wingard & Berkman 1983).

The relationship between duration of sleep and vascular events (stroke, heart disease) is U-shaped similar to the mortality figures above. Long duration of sleep is associated with higher risk of coronary heart disease, stroke, and total cardiovascular disease. (Capuccio et al. 2011). But the mechanisms for these associations are not fully understood.

Longer sleep durations are usually associated with other co-morbid illnesses. Short duration of sleep is also related to adverse health consequences including obesity, impaired glycemic control, increased cardiovascular risk, and activation of low-grade inflammation. Associations of sleep duration and mortality do not mean causality. However, I agree that under current times, many people are sleep-deprived, which also has negative health consequences.

For most adults, we recommend 7-8 hours of sleep. The key message is to get enough sleep to fulfill your health needs. Your ability to remain alert and functional the entire day especially after meals is a good indicator of adequacy of hours of sleep.

Simple test to find out optimal sleep times: If you are sleepy, maintain your wake-up time constant and go to bed earlier by 15 minutes for a week and reassess your daytime function. Keep moving your bedtime back in 15-minute increments weekly and maintaining the same wake-up time until you are alert the entire day. That should be your usual bedtime and wake-up time.

Is too much sleep bad for you?

Vadim Rotenberg has answered Unlikely

An expert from Tel Aviv University in Sleep Research

I suppose that this question does not take into consideration, that an increased requirement in sleep really may be a sign of psychological problems that need REM sleep ( and consequently the increased sleep duration) for the restoration, but it depends on the functional efficiency of REM sleep. If it is high enough, to have an increased sleep is good for me, but if it is functionally inefficient the long sleep is only a sign of psychological problems that can not be satisfied, and in this condition increased sleep duration is only a sign of the unresolved problems what is bad for me. Youcan aply with this question to all specialists in sleep investigations.

Is too much sleep bad for you?

Erika Bagley has answered Unlikely

An expert from Muhlenberg College in Sleep Research

The research presented here suggests that this was an observational study and therefore impossible to derive conclusions about sleep “causing” these outcomes. While I don’t doubt the statistics, the interpretation is complicated. Getting 9+ hrs of sleep consistently might be related to a number of other things such as chronic depression, poor physical health, poor diet, etc. It might also suggest that the quality of sleep is rather bad (people are in bed longer because their sleep is less restful). These related behaviors might be what actually explains the negative health outcomes they found in the study. There are experimental sleep restriction studies that show lack of sleep can cause disruptions in cognition, metabolism, and mood. No such experimental studies of “too much sleep” exist, so conclusions that suggest too much sleep causes these negative health effects are tenuous.

Is too much sleep bad for you?

Jamie Zeitzer has answered Unlikely

An expert from Stanford University in Sleep Research

There are many studies out there that show an association between long sleep and negative outcomes (both specific aspects of health and overall mortality). The relationship between sleep and these outcomes are often U-shaped, such that both short and long sleep are associated with negative outcomes. The problem with interpreting this as “long sleep is bad for you” is that we don’t know why the long sleepers have bad outcomes. It might be that they are sleeping a long time because there is something medically wrong that induces great sleep (sleep is great for fixing things) or might be that getting long sleep is actually doing damage, though there isn’t good data to support that. Many long sleepers, however, are just genetically programmed to need more sleep (there is a bell curve distribution of the amount of sleep that people get). What we really need to know is if someone has always been a long sleeper or if they developed this later in life – this would help us to understand the relationship between extended sleep and medical outcomes.

Is too much sleep bad for you?

Robert Stickgold has answered Extremely Unlikely

An expert from Harvard University in Sleep Research

The article cited in this news report actually says they’re talking about people getting more than 9 hours of sleep, not people getting “to much sleep”. To my knowledge, there is no evidence that it’s even possible to get too much sleep. It seems reasonable that people who are seriously ill might need more sleep than their healthy counterparts. In that sense, getting more than 9 hours of sleep a night might suggest the presence of such an illness. But in such cases, I would think that decreasing the amount they slept would make things worse.

Is too much sleep bad for you?

John Axelsson has answered Unlikely

An expert from Karolinska Institutet in Sleep Research, Cognitive Science, Psychology, Immunology

While epidemiological show a U-shaped curve betgween sleep duration and adverse health outcomes, it is unlikely that sleeping longer, per se, is a risk factor. First, the fact that many phenomena, such as sleep need and sleep duration, are normally distributed may explain that being further away from the normal can explain part of this vulnerability. Being in the extremes of a normal distribution is often a risk factors. This means that those who have a larger sleep need, or being more vulnerable to sleep disturbances are more likely to suffer when sleep is disrupted or shorter than their need due to factors such as eaerly starting times at work.

Second, a long self-rated sleep duration can be driven by a number of diseases or disorders, particularly those related to inflammation, fatigue or if the disorder disturbs the sleep (e.g. pain) so people have to spend longer time in bed to get the same amount of sleep. A note is that people are much better at judging their bed times than their sleep time. Studies measuring subjective aspects of sleep would benefit from focusing on time in bed rather than sleep duration.

A third aspect is that longer sleep is related to other health behaviours such as being married, having a job, being physically active, and this bias is hard to adjust for completely.

Is too much sleep bad for you?

Christian Benedicte has answered Unlikely

An expert from Uppsala University in Neuroscience

Sleep is your friend, not your foe! One explanation for the link between long sleep and poor health involves disrupted sleep patterns. Insomnia and obstructive sleep apnea (OSA) – constituting major sleep disorder categories – are manifested with impaired nocturnal sleep quality, including single or recurrent long-lasting wake episodes after sleep onset, frequent awakenings after sleep onset, light sleep, extended sleep onset, low sleep efficiency (typically defined as time asleep divided by time in bed), and excessive daytime sleepiness. Given that especially deep sleep (also known as slow-wave sleep, SWS or sleep stage N3) has been proposed to be restorative and also to reduce sleep pressure [light and fragmented sleep may not sufficiently reduce sleep pressure generated during daytime wakefulness, and could therefore result in prolonged habitual sleep duration.

Is too much sleep bad for you?

Dale Rae has answered Extremely Unlikely

An expert from University of Cape Town in Sleep Research

It is true that there is a U-shaped relationship between sleep duration and increased mortality (all cause and cardiovascular disease) – but this does not imply cause and effect. In fact, it is important to interpret the association between short sleep and poor health quite differently to that between long sleep and poor health. While there is evidence to suggest that short sleep negatively affects metabolism and increases risk for obesity and cardiometabolic diseases, for example, there is no experimental evidence to show that “too much sleep is bad for you”. Rather, it is more likely that those people who do have longer sleep needs are suffering from some other physical or mental condition, one of the symptoms of which may be longer sleep. Alternatively, long sleepers may have poor quality (non-restorative sleep) sleep, to which they respond by trying to increase sleep duration.

Is too much sleep bad for you?

Jo Caldwell has answered Likely

An expert from Naval Medical Research Unit in Neuropsychology

The optimal amount of sleep seems to be about 7 solid hours. For each hour below that amount, there are additive adverse health consequences, and for each hour above the 7 hours there are additive adverse health consequences. There is debate as to why there would be an association between long sleep and increased disease and mortality. Keep in mind that the known relationship between sleep and health is based on epidemiological studies and not (for the most part) on controlled investigations. Because of this, it’s possible that there is some intervening variable responsible for the link between long sleep and mortality risk such as the likelihood that people who are already ill are sleeping longer because of their illness and are also likely to die prematurely because of the illness. In other words it’s the ILLNESS that is actually causing both things–the long sleep and the premature death–and not the LONG SLEEP that is directly causing either the illness or the premature death. That’s probably the case. Here is a link to one of the best articles I’ve seen on this issue (http://jaha.ahajournals.org/content/6/9/e005947). Check out the graphs and then go to the Discussion section and read what the author has to say about the “U-Shaped” relationship between sleep duration and health. He/she/they do a GREAT job of providing some clear-cut evidence as well as very logical explanations.

Is too much sleep bad for you?

Erik  Wibowo has answered Unlikely

An expert from Dalhousie University in Neurobiology, Oncology

The answer to your question is not simple. People may sleep longer in response to sleep deprivation or because of medical conditions/treatment. But each person usually has their own optimal sleep amount. For example, one may usually sleep less than 7 hrs and feel fine on the next day (though this could also be due to an allostatic response to prolonged partial sleep restriction), while others need more than 8 hrs to feel adequate sleep. Age is also a factor that will influence how much sleep one requires (See: https://www.ncbi.nlm.nih.gov/pubmed/29073412). Suffice it to say, there is a recent review suggesting that long sleep duration (> 9 hrs) may have negative health outcomes. (For more details see: https://www.ncbi.nlm.nih.gov/pubmed/28890167 and https://www.ncbi.nlm.nih.gov/pubmed/26194576). But again, various factors (amount of physical activities, diet, comorbidities, etc) may influence/contribute to the negative health outcomes. One would need to explore why a person sleep excessively before concluding if longer sleep amount is good/bad.

Is too much sleep bad for you?

Daniel Cohen has answered Unlikely

An expert from Sentara Heart Hospital in Neurology, Sleep Research

Excessive sleep times are associated with increased adverse cardiovascular events including mortality. However, this association is likely correlative rather than causative – it is likely that habitual excessive sleep duration is a marker for an unhealthy state. Experiments in healthy volunteers suggest that we can’t physiologically “over-sleep” once we have recovered from a chronic sleep debt. Sleep itself is not likely to be harmful. We should therefore not purposely avoid sleep for any health concerns.

Is too much sleep bad for you?

Karen Matthews has answered Unlikely

An expert from University of Pittsburgh in Psychology, Epidemiology

To my knowledge there is no experimental data indicating too much sleep is bad; there is observational data (epidemiology) that people who sleep 9 hours or so or more are at greater risk for diabetes, heart disease, and obesity. The numbers of people who sleep that long are pretty low in the general population.

Is too much sleep bad for you?

Michelle Olaithe has answered Likely

An expert from University of Western Australia in Psychology, Sleep Research

Yes, you can get too much sleep. Sleep is much the same as any other basic requirement for life. Just as you can eat too much, you can sleep too much. Let’s look at a few ways ‘too much sleep’ has an impact on us.

Too much sleep is negatively associated with quality of life (Groeger et al. (2004) Journal of Sleep Research), can impact your sleep quality, and leave you feeling unrested the next day (Pilcher et al. (1997) Journal of Psychosomatic Research). Further, too much sleep is associated with a higher risk of morbidity and mortality (e.g., Ferrie et al., (2007) Sleep). This list does continue!

With this in mind, these studies are analysed at the group level, so what might be generally ‘too much’ may not be the case for any one individual. A sleep diary (http://bit.ly/2Een1LX) is a great way to figure out what your ‘ideal’ amount of sleep is, and have a read of the Sleep Health Foundation fact sheets (www.sleephealthfoundation.org.au) for some great sleep tips.

Is too much sleep bad for you?

William Killgore has answered Unlikely

An expert from University of Arizona in Sleep Research, Neuroimaging, Neuroscience

There is no convincing experimental evidence showing that increasing sleep time, in and of itself, is harmful. As mentioned by most of the experts who have responded to this question, non-experimental population-based studies have long shown the U-shaped association between sleep and health problems/mortality. Unhealthy people tend to be found at either end of the curve. What we do know is that people who are suffering from various illnesses or disease states often sleep too much or too little. The most likely explanation for the associations with long sleep is that the disease state is what leads to excess sleep, probably not the other way around. But without prospective experimental evidence, it remains a bit of a chicken-and-egg question. Perhaps the important thing to take away from the article is to be aware of your own individual sleep need and consider how far it deviates from the typical 7-hour level. If you find you are needing a lot more than 7-hours to function effectively, or if the amount of sleep you need has increased significantly, it might be something to bring up with your doctor. The increased sleep itself may not be hurting you, but it might be telling you that something else is.

Is too much sleep bad for you?

Ralph Mistlberger has answered Unlikely

An expert from Simon Fraser University in Sleep Research

Concern about getting too much or too little sleep comes, in part, from ‘epidemiological’ studies that have found associations between self-reported sleep duration and various health problems (e.g., cardiovascular disease, metabolic disorder, cancer, all-cause mortality, etc) in large groups of people. For most of these conditions, including mortality, the association is U shaped, with worse outcomes for those who report sleeping 6 hours or less, and also for those who report sleeping 9 hours or more. The cutoffs for these negative associations vary a bit from study to study, but most report 7-8h as the ‘sweet spot’, where health scores are best and mortality is lowest. The results of these studies are often taken to imply that sleeping too much or too little ’causes’ the health problems. However, it is possible that the things that cause you to sleep less than the average person (‘stress’?) or more than the average person (depression, disease?) are what cause the health problems. The amount that you sleep may not be the cause. We need experiments to establish causality. We do have some experimental evidence that short sleep can be bad. Volunteers who are restricted to <6h of sleep per night for as little as a week begin to show changes in metabolism (e.g., insulin sensitivity) that eventually would result in metabolic disorders (e.g., obesity, diabetes) if the sleep restriction was chronic. This establishes a plausible mechanism by which chronically restricted sleep could cause metabolic or other disorders. There is no comparable evidence that sleeping for 9 hours or more per night does anything bad to the body or brain. The ‘right’ amount of sleep for you is the amount that allows you to feel rested for most of the day. Don’t let anybody scare you into restricting your sleep to 7 hours per night, if that makes you chronically sleepy; there is no evidence that sleep itself is unhealthy.