By Virginia Gurley, MD, MPH
MB (Marc Braman, MD, MPH):
Our topic this session is how to strengthen your immune system with sleep.” Welcome back, Dr. Gurley.
VG (Virginia Gurley, MD, MPH):
Thank you, Dr. Braman.
MB:
This session we are talking about sleep and its connection to how well our immune system works. The immune system is complex and plays an important role in protecting our health from threats ranging from colds to cancer. How does sleep impact the strength of our immune system?
VG:
Well, you summed it up very nicely Dr. Braman. Sleep impacts the full range of how well our immune system works from how likely you are to catch a cold and to the risk for developing serious immune mediated diseases like autoimmune disorders and cancer.
MB:
Ok, so let’s tease this apart a little bit and look at the impact of sleep on immunity. What do we know about sleep and our chances of catching an infection?
VG:
There have been quite a number of studies that suggest short sleep time and poor quality sleep increases one’s risk for catching a variety of infections. One particularly strong recent study compared the chances of developing a cold in people who sleep six or fewer hours per night to people who sleep seven or more hours. After actually putting a cold virus in each of the study subject’s nose, what they found was that people who slept six or fewer hours per night were four times more likely to develop cold symptoms than the people who slept seven or more hours.
MB:
Wow, 4 times greater chance of catching a cold when we sleep six hours or less – that is a huge difference! Of course colds are no fun, but they’re not usually a big threat to our long-term health. What about auto-immune diseases? You mentioned increased risk for these serious disease, what can you tell us about that.
VG:
Autoimmune diseases are a big group of disorders including lupus, rheumatoid arthritis, scleroderma and Sjogren’s syndrome. And, unlike infections, where the immune system doesn’t attack strongly enough to kill off a virus or bacteria, in autoimmune diseases, the immune system over reacts and mistakenly attacks and damages many cells and organs within the body. And what an increasing number of studies are finding is that poor sleep increases the risk for developing autoimmune diseases.
MB:
Interesting. What can you tell us about these studies?
VG:
One study compared people who were newly diagnosed with a sleep disorder, not including obstructive sleep apnea, to people who did not have a sleep disorder to see how many people in each group developed an autoimmune disease. This was a very big study with nearly 85,000 people in each group, and what the researchers found was that people in the sleep disorder group were 50% more likely to develop an autoimmune disorder during the following three years.
MB:
Impressive. So not enough sleep and poor quality sleep can both weaken the immune system, so that we catch colds more easily, and can over-activate the immune system, so that cells and organs are more likely to be attacked and damaged by our own immune system. Sounds like sleep is good lifestyle medicine for restoring healthy immune system function just like it does for other systems. Thank you, Dr. Gurley!
VG:
Thank you, Dr. Braman.
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