Stress and our Circadian Rhythms
I was recently telling my friend about my poor sleep patterns and he said my circadian rhythm was off. What is a circadian rhythm and how does it affect the body?
Circadian rhythms have an effect on body temperature, sleep/wakefulness and various hormonal changes according to The University of California-Los Angles, UCLA Sleep Center. All animals and plants have a built-in circadian rhythm, our internal body clock, also known as our circadian clock.
The word circadian comes from the Latin word meaning "about a day" and involves two critical pathways. The first pathway, and the most important, responds to light and has been well characterized. The brain's internal circadian clock is centered in the hypothalamus region of the forebrain, uses Zeitgebers (time-givers) to naturally synchronize itself to within just a few minutes of the Earth's 24-hour rotation cycle.
Humans are diurnal animals and are naturally active during daylight. The second pathway, which is less understood, is how the body responds to food. Although the research data seems to be poorly compiled, there are body functions that have been linked to the circadian rhythm.
According to Dr. Makoto Akashi, of the Yamaguchi University in Japan, dietary manipulation may play a valuable role in adjusting the circadian clock. Researchers found that insulin, a pancreatic hormone, is secreted in response to feeding and may be involved in resetting the circadian clock.
Researchers at the Brigham and Women's University Medical Center in Boston did conclude that periods of irregular sleep resulted in a rise in blood glucose and a drop in metabolic rate. While the brain was originally thought to be the main controller of our circadian clock, the liver and the intestines have their own circadian rhythm like the pancreas. As an example, peak energy level for the stomach occurs between 7 a.m. and 9 a.m.
Hence the reason breakfast is the most important meal of the day.
While it is common knowledge that the stomach secretes digestive acid with each meal, it is still somewhat a mystery as to why the stomach secretes two to three times more acid from 10 p.m. until 2 a.m. Perhaps the brain is the conductor of the symphony and coordinates the action of the stomach and other organs. Our circadian rhythms can be disrupted by jet lag, lack of sleep, shift work, some medications and eating at unusual times.
Abnormal circadian rhythms are linked with problems like insomnia, fatigue, depression and type 2 diabetes.
Now, more studies are linking a disruption in circadian rhythms to weight gain. The secret: SSSHHHH - Get enough sleep!
Thought for the week: One's mind, once stretched by a new idea, never regains its original dimension! Oliver Wendell Holmes
Phylis B. Canion is a doctor of naturopathic medicine and is a certified nutritional consultant; email her at email@example.com. This column is for nutritional information only and is not intended to treat, diagnose or cure.