Association of Sleep and Chronic Illness

A recent PatientsLikeMe survey found a strong correlation between chronic illness and poor sleep. Here are the most interesting results:

PatientsLikeMe survey respondents in the U.S. (n=3,284) . . . are almost nine times more likely to [have] insomnia than the general adult population. . . . PatientsLikeMe members with health conditions experience [each] of the four symptoms of insomnia [= trouble falling asleep, trouble staying asleep, early awakening, and waking up not rested] at twice the rate of the general adult population.

This supports my view that bad sleep causes illness. The correlations could have plausibly been the other way (better sleep among survey respondents). People sleep more when sick. Whatever makes sick people sleep more might also make them fall asleep faster and wake up less often.

If I slept poorly, I would move heaven and earth to sleep better. (But would never take sleeping pills.) I sleep well, actually, but I still track my sleep and do various experiments to see if I can improve it. For example, recently I was puzzled why I was sleeping less well in Berkeley than in Beijing. One possibility was that my Beijing bedroom was darker than my Berkeley bedroom, even though my Berkeley bedroom was quite dark (e.g., no light from a street lamp). I made my Berkeley bedroom even darker and found my sleep improved. It really was cause and effect. When I made my Berkeley bedroom lighter, my sleep got worse.

My enormous concern with sleep — nothing matters more for health — seems to put me in a tiny minority. Even sleep researchers don’t say bad sleep causes sickness. However, Robb Wolf agrees with me. He has said, “If someone sleeps poorly it is hard to keep them alive. If someone sleeps well, it is hard to kill them” — a good way of putting it. At the recent Ancestral Health Symposium in Atlanta, I asked him where he got this. He said it was based on his experience, meaning his experience working with other people.

My view is heavily based on my experience of my own health. Exactly when I greatly improved my sleep, I greatly improved my health. I stopped getting obvious colds. The people around me continued to get them. I hadn’t expected this. In the research literature I found plenty of support for the idea that better sleep causes better health. An example is that poorer health during the winter seems to be due to less light, not the cold. I am sure morning sunlight improves sleep. Vitamin D has been associated with dozens of measures of health (more Vitamin D, better health). This too may reflect the underlying causality better sleep –> better health because sunlight increases Vitamin D and improves sleep. That morning Vitamin D improves sleep (Tara Grant’s great discovery) be important here. Epidemiologists should always measure sleep the way they always measure smoking. Now they almost never do.

Thanks to Richard Sprague.

More “Even sleep researchers don’t say that bad sleep causes illness” — that’s wrong. Here’s an example:

Yet there’s strong evidence that lost sleep is a serious matter. The Sleep in America polls and several large studies have linked sleep deficits with poor work performance, driving accidents, relationship problems, and mood problems like anger and depression. A growing list of health risks has been documented in recent studies, too. Heart disease, diabetes, and obesity have all been linked with chronic sleep loss. ”People just don’t realize how important sleep is, and what the health consequences are of not getting a good night’s sleep on a regular basis,” Hunt tells WebMD. “Sleep is just as important for overall health as diet and exercise.”

I should have said sleep researchers don’t connect good sleep with good immune function, which this quote illustrates.

15 Responses to “Association of Sleep and Chronic Illness”

  1. David Says:

    Not that I doubt the importance of sleep, but in this case couldn’t the causation easily go the other way: if you’re chronically ill, that illness interferes with your ability to sleep?

  2. Char Says:

    Here Stephan Guyenet discusses sleep and obesity. He mentions Dan’s Plan (http://www.dansplan.com/blog/index.php) where it’s been discussed also.
    I find this interesting.

  3. Char Says:

    Whoops! Forgot the link to Stephan Guyenet’s blog: http://wholehealthsource.blogspot.com/2013/10/sleep-and-genetic-obesity-risk.html

  4. Michael Says:

    Seth, I think you are correct that bad sleep causes illness. However, that people sleep more when sick, is imo generally true more so for acute than chronic disease. I believe that in chronic disease one may find oneself in a vicious cycle: poor sleep contributes to the chronic condition, the chronic condition in turn (e.g., through pain) contributes to poor sleep. A very tough proposition.

  5. Alex Chernavsky Says:

    “Even sleep researchers don’t say bad sleep causes sickness.”

    About five years ago, I attended a lecture by Cornell psychologist James Maas. He did point out various ill effects of sleep deprivation, although he seemed to focus mainly on people who voluntarily deprive themselves of adequate sleep.

  6. Stu Says:

    Most days I wake up feeling more tired then when I went to bed the night before, however I find that if I take up to a tablespoon of raw honey immediately before bed I almost always wake up feeling totally refreshed. I’ve suffered from low energy, brain fog, fatigue and sore muscles for years and I tried eliminating food groups (dairy, grains, nightshades, etc) but that didn’t fix the problems (although wheat has been problematic) but taking the honey did.
    I usually sleep without any problems that I’m aware of even if I awaken feeling unrefreshed I will still sleep through the night and won’t awaken early or whatever, but the crucial thing is I feel rested when I wake up, if I get that right I can even eat bad food and feel good all day. I’ve tried coconut oil and coconut oil combined with honey but they didn’t work.
    I’ve also noticed caffeine later in the day and chocolate have a huge impact on this. There are a lot of factors that come in to play so the honey thing doesn’t always work, but it can make a big difference. I think the fructose helps replenish liver glycogen which may help me get more deep sleep but I don’t know for certain

  7. Seth Roberts Says:

    That’s fascinating. You write: “I’ve also noticed caffeine later in the day and chocolate have a huge impact on this.” Could you elaborate? Huge impact in what way?

  8. Seth Roberts Says:

    Yes, Maas does say this. This is from a Cornell press release about a book by Maas:

    The book also includes two tests to help the reader determine how well they sleep, the costs of sleep loss and research findings that link poor sleep with colds, flu, unhealthy skin, weight gain, diabetes, heart disease and cancer, as well as stress, anxiety and depression.

  9. Stu Says:

    I’ve noticed a while ago that for some reason if I drank coke with dinner I always felt terrible the next day and didn’t sleep well even though I would avoid sugar most of the time. I thought it was the sugar that gave me hangover like symptoms and unrefreshed sleep, but I had done ‘carb back loading’ with heaps of sugary foods and junk and slept well after, but if I drank coke I didn’t feel refreshed the next day. After a while I realised it might be the caffeine.
    Also I noticed that the honey wasn’t as effective if I had caffeine in the afternoon or evening. Alcohol seems to effect sleep also for me – it helps me sleep but I don’t wake up feeling refreshed. It’s so hard to get everything right. Recently I tried drinking one cup of tea at 10am and no caffeine after, I found that I felt terrible in the middle of the afternoon but that night I had really vivid dreams, two of the dreams that night were flying dreams which was cool. I think eating chocolate after dinner kind of messes things up also, but a glass of milk without chocolate has similar effects to honey. But it gives me acne…
    I’ve even got to the point where I think that flossing before bed and brushing my teeth improves my sleep but that’s just ridiculous! The honey and caffeine thing makes sense but the oral hygiene thing is probably a bit far fetched. I do have a lot of light exposure though in the evening so I haven’t really dealt with that as a factor. I’m also a little worried that the honey might raise my set point so I don’t always do it, plus I think it isn’t as effective if you do it everyday for some reason.

  10. Stu Says:

    Also I forgot to mention: refreshed sleep = low (normal) appetite the next day and fasting is easy, unrefreshed sleep = insatiable (unsatisified appetite) the next day/can’t stop thinking about food!

  11. Vic Says:

    Seth, how important to your sleep are sleep position (back, stomach, size) and mattress firmness?

    Seth: I don’t pay attention to any of that. Sometimes I wonder what effect it would have if I slept on the floor but I haven’t found out.

  12. nansen Says:

    How exactly do you make your Berkeley bedroom even darker? Have you considered wearing a sleep mask, or do you still want the dawn light to get through?

  13. Jeff Winkler Says:

    Confirmatory study and an cheap DIY intervention–

    Michael Mosley (of Eat Fast) participated in a study where the changed sleep from 6.5 to 7.5 hr, and did blood draws for quick feedback. A summary is at http://www.bbc.co.uk/news/magazine-24444634. Think the meat is in the video, but it’s region-blocked :(

    (Seven) volunteers were randomly allocated to two groups. One group was asked to sleep for six-and-a-half hours a night, the other got seven-and-a-half hours. After a week the researchers took blood tests and the volunteers were asked to switch sleep patterns. The group that had been sleeping six-and-a-half hours got an extra hour, the other group slept an hour less.

    the most interesting results came from the blood tests that were run.

    Dr Simon Archer and his team at Surrey University were particularly interested in looking at the genes that were switched on or off in our volunteers by changes in the amount that we had made them sleep.

    “We found that overall there were around 500 genes that were affected,” Archer explained. “Some which were going up, and some which were going down.”

    What they discovered is that when the volunteers cut back from seven-and-a-half to six-and-a-half hours’ sleep a night, genes that are associated with processes like inflammation, immune response and response to stress became more active. The team also saw increases in the activity of genes associated with diabetes and risk of cancer. The reverse happened when the volunteers added an hour of sleep.

    ================
    Improving sleep quality by blocking blue light @night. Seth, what color were the lights in your Berkley bedroom?
    Sanjiv Shah – Sleep and Tinted Goggles – Boston QS – http://vimeo.com/64204620

    Reduced sleep latency, more deep sleep (per Zeo). Works for me, and the glasses are $9. No-brainer.

  14. Seth Roberts Says:

    I made my Berkeley bedroom darker by lowering the blinds. In Beijing I hang big towels over the windows.

    Yes, I have considered wearing a sleep mask. It’s something I plan to try. I don’t worry about dawn light while asleep any more since I wake up before dawn.

  15. Stu Says:

    I was under the impression that sleep cycles followed a 90 minute ultradian rhythm… If that’s the case then 7.5 hours sleep would be ideal as you would awake towards the end of the cycle whereas people sleeping 6.5 hours would be awoken in the middle of the cycle. Perhaps that could be something to consider, maybe 6 hours would be better than 6.5 hours