Does a stressful sleep cause disease?

Our entire lives we produce cancer cells, yes you read correctly, cancer cells. At the same time, a miraculous finely-tuned group of systems work silently, day and night, to spot and destroy these cells. When things run well, it works like clockwork… in perfect harmony. Disruptions, especially if they go on for longer periods, may be catastrophic. The finely-tuned systems we refer to here are sleep and hormones.

After analysing many studies, Dr. D. Spiegel, from the Stanford University, says that “sleep problems alter the balance of at least two hormones that influence cancer cells.” One of these hormones is cortisol. This hormone is vital in the regulation of the immune system, including the release of “killer cells” that will destroy cancer cells. Cortisol levels typically peak at dawn after hours of sleep, and then they decline during the day. It is for this reason, Dr. Spiegel says, that “night shift workers, who have higher rates of breast cancer than those who sleep normal hours, achieve their cortisol peak in the afternoon and not in the morning like the rest.”

Another important finding is that cortisol or “stress hormone” as many call it, may play a direct and essential role in the development of diseases like cancer. Too much of it is a recipe for misery and we know that people who wake up repeatedly during the night are more likely to have high cortisol levels.

The second hormone affected by sleep is melatonin. The brain produces this hormone before we go to bed and when we sleep. Melatonin is one of the strongest antioxidants that helps prevent damage to cells that can lead to cancer.

In the case of female shift workers, Dr Spiegel says that women who are up all night produce less melatonin. Women, in particular, should not forget that melatonin lowers oestrogen production from the ovaries. Therefore, a lack of sleep leads to too little melatonin, exposing women to higher levels of oestrogen and therefore, a higher risk of developing breast cancer.

Bad sleepers do not produce enough melatonin but produce too much cortisol. This formula is detrimental to your health!

Dr. Spiegel’s advice is very simple: “Do what your grandmother told you to do: eat well, sleep well and work hard and you will help your body to stay healthy”.  (In our days, the last part of Grandma’s advice translates into lots of exercise.) The bottom line says Dr. Spiegel, is that “there is enough scientific information available to understand that cancer can be influenced by the amount of stress to which we are exposed and the quality of sleep we get.”

To end, the scientist at Stanford University does not mention anything about the sleeping partner, but we may conclude that as long as yours keeps your stress levels low, he/she must be the right one. Don’t you think so?

Sources
¹Does Stress Cause Cancer? Spiegel. D. and Septhon S. Brain, Behaviour and Immunity, 2003: 17: 321-328.