“A good laugh and a long sleep are the two best cures for anything.” – Irish Proverb

You don’t need the luck of the Irish to fight off your next cold. Better sleep is proven to boost immunity. Sleep deprivation compromises your body’s ability to defend itself against illnesses and infections. A recent study showed that getting just one hour less sleep a night for a week can compromise immunity by 44%. When sleep deprivation continued for a month, it jumped to 97% (source, p.32).

In another study, researchers compared the immunity of sleep deprived individuals with well rested individuals over two weeks. Participants were given nasal drops that contained the common cold. Those who averaged less than 7 hours a sleep a night were nearly 3 times more likely to get the cold than those who slept for more than 8 hours (source, p. 11).
These studies all serve to further illustrate the importance of a good night’s rest. While we sleep, our bodies are busy creating vital disease-fighting substances. These hormones, proteins and chemicals are responsible for fighting off possible infections. Trying to get by on too little sleep decreases their availability, leaving you susceptible to unfriendly viruses and bacteria (source).
“A lot of studies show our T-cells go down if we are sleep deprived,” says Diwaker Balachandran, director of the Sleep Center at the University of Texas M.D. Anderson Cancer Center in Houston. “And inflammatory cytokines go up… This could potentially lead to greater risk of developing a cold or flu” (source).
Aside from playing a significant role in determining whether or not we come down with a cold, sleep deprivation also influences how our body responds if and when we do become sick. Since we lack the proper resources to defend ourselves against whatever is ailing us, we end up being sick for a longer period of time.

It also helps us fight off much more serious health conditions.
Researchers found that sleep deprived mice developed more aggressive tumours, had faster cancer growth, and were less able to defend against the earliest stages of cancer than their well-rested counterparts (source, p.112). There are many other studies that link sleep deprivation with cancer. In fact, the International Agency for Research on Cancer has now classified overnight shift work as a Group 2A carcinogen (source, p.63).
Part of our body’s response to a lack of sleep is to send our sympathetic nervous system into overdrive. This provokes an inflammation response from the immune system; some cancer cells can then attract inflammatory components into an already existing tumor, feeding it more nutrients and oxygen.
As research into this area continues, more and more studies reveal how our cancer-fighting cells are affected by even a brief period of insufficient sleep.
Examining healthy young men at the University of California, Dr. Michael Irwin found that just one night of four hours of sleep removed roughly 70 % of the cancer-fighting cells flowing throughout the immune system (source).

While adults typically require 7-8 hours a night, it depends entirely on the individual and their respective physiological needs. Some people are simply better able to handle the physical demand of getting by on less sleep, and have a system that allows them to function longer without getting run down. Those with a weaker immune system are more prone to sickness if they’re not getting enough rest (source).
Get to know your individual needs and your immune system will thank you.