It's been said that timing is everything, and that may be particularly true when it comes to the body's ability to fight off disease. If you've read our page on the importance of sleep, you may remember this clock that Traditional Chinese Medicine uses to explain the shifts in body function throughout the day. An Organ is thought to be at its strongest, and to rule over the function of the body during its time period. When someone has a symptom at the same time each day, we consider that there may be an imbalance with that Organ System. For example, someone who wakes up regularly around 2 AM may have an imbalance in the Liver, such as Liver Qi stagnation or Liver Blood deficiency.

In Western scientific thought, a similar cycle of internal timing and regulation is called circadian rhythms, or the circadian clock, which regulates a lot of metabolic activities over a twenty-four hour cycle. In the past two years, scientists have started to understand this body clock and its effects on our health more deeply, finding that:

People who work night shifts have a higher risk of type 2 diabetes and heart disease. Studies have also found that if volunteers have their sleep disrupted repeatedly for three days, they temporarily develop symptoms of diabetes.
There is an increase in heart attacks following the time change with Daylight Savings. "The Monday and Tuesday after moving the clocks ahead one hour in March is associated with a 10 percent increase in the risk of having a heart attack," says UAB Associate Professor Martin Young, Ph.D., in the Division of Cardiovascular Disease. "The opposite is true when falling back in October. This risk decreases by about 10 percent." Also, heart attacks that happen in the morning hours between 6AM and noon tend to be the most serious.
Circadian rhythms play a role in the ability of skin cells to regenerate. Disruption of the body clock can result in premature tissue aging and a greater chance of developing skin tumors.
The extreme 'mood swings' in bipolar disorder have been strongly associated with disruptions in circadian rhythms and sleep disorders.

New research published in the February issue of the journal Immunity shows that the success of our immune defense depends in part on our "body clock." Dr. Erol Fikrig from Yale University School of Medicine, a senior study author, states "It is becoming increasingly evident that disruption of daily rhythms, such as from sleep deprivation, affects the immune response," Indeed, Dr. Fikrig and colleagues found that important immune system proteins that sense bacteria and viruses had cyclical changes that corresponded to certain times of day - their response was lowest in the early morning hours. The authors suggest that their observations may be important as patients who are in sepsis are known to be at increased risk of mortality between 2 and 6 am.

In TCM, the Organ system most important to immunity is the Lung, which is most active between 3-5 AM. The two clocks don't line up exactly, but the concept is the same - our bodies have a certain ebb and flow. Too much light in the nighttime and increased cortisol levels (from stress), among other factors, can throw off your circadian clock and interrupt your body's cycles. Dramatic changes to that cycle, and missing out on sleep in the late night/early morning hours can really effect your health and susceptibility to disease.

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