The Biological Clock and Its Effect on Health

If you notice that you are ill more often in certain seasons, or that you are more tired or hungry at particular times of day,

or that you are more irritable on certain days of the month, you are noticing the work of your body's biological clocks.

The biological clock is located in the front part of the brain and is responsible for many physiological processes in our body.

Taking its rhythm into account can help us live healthier, more satisfying lives. More details follow in this article.

Yoram (not his real name) came for nutritional treatment because of a series of health problems he had experienced for years.

His most difficult complaints were digestive problems (he had been diagnosed with irritable bowel syndrome) and fatigue.

As we worked together, an interesting issue emerged: Yoram was completely unaware of his body's natural biological clock. Consequently, his nighttime meals kept him awake into the small hours because otherwise he suffered severe heartburn. He could not concentrate on tasks he took on in the afternoon, the physical activity he had chosen made falling asleep difficult, and so on.

Yoram's story reminded me of my own experience with the biological clock. Several years ago, I traveled with my family on a Jewish Agency assignment to another country, Russia. We landed in the northern city of St. Petersburg and encountered a phenomenon unique to this region: from late spring to late summer, daylight hours grow very long and occupy much of the day. This is known as the "white nights." In fact, there is almost no darkness. The sun shines during the day, and at night the light resembles early morning here, before sunrise.

What do you think happened to me? That's right, I stopped sleeping! I could barely sleep 3-4 hours a day, and despite being tired, I could not make up the sleep I was missing.

It turns out that my biological clock was working as it should. Apparently, so was my patient Yoram's.

Here is one definition of the biological clock (the circadian clock, meaning approximately a day) that I found online:

A regular internal activity rhythm produced by unknown mechanisms, independent of external time signals. Higher organisms have a series of clocks arranged by importance. For example, although body temperature and activity cycles are generally "set" to 24 hours, the two cycles can vary independently, showing that two clock mechanisms are involved.
Exposure to bright light (phototherapy) can alter the biological clock and help, for example, people suffering from jet lag and seasonal depression (the "Hayadan" website)

It is known, for example, that rates of depression and even suicide in northern countries are higher than the average in the Western world. Shift workers may experience much higher rates of diseases such as diabetes, heart disease, and cancer.

According to Chinese medicine, every meridian (an energy pathway associated with a particular organ) has peak and low periods. For example, the liver meridian, responsible for draining toxins from the body, is most active between 01:00-03:00 at night. The large intestine meridian, responsible for absorbing fluids from the digestive system back into the body, forming stool, and expelling it, is most active between 05:00-07:00 in the morning. The stomach meridian wakes between 09:00-11:00, and so on.

The biological clock operates throughout the day, throughout the year, and throughout our life cycles. For example, the transitional seasons, fall and spring, are known to be troublesome times for worsening inflammatory digestive diseases, stomach ulcers, and similar conditions.

In summer, by contrast, the risk of infectious diarrhea is greater, while winter brings a greater risk of respiratory illness.

There are cycles during our lives that require special attention to our health. For example, uptake of the mineral calcium into bones is most efficient until around age 30. After menstruation stops, women experience a further significant decline in calcium uptake into bones, and the risk of osteoporosis (loss of bone mass) rises. Our fertility cycles, the development of secondary sexual characteristics, and sleeping and waking hours differ at different ages.

Our metabolic rate is also influenced by an internal biological clock. Our body builds fat cells during two periods of life: infancy, in our first year, and adolescence, as a child becomes a sexually mature teenager. From then on, we can mainly fill or empty existing fat cells, rather than build new ones or eliminate old ones.

The same applies to our daily rate of calorie burning. Do you know the saying "Eat breakfast like a king, share lunch with a friend, and give dinner to your enemy"? This is an old folk recommendation for eating in line with our metabolic rhythm. Nighttime eating necessarily becomes more problematic, places a greater burden on digestion, and may also be more "fattening." At night, our body needs rest, not food to digest.

The same applies to physical activity: our metabolic rate is faster in the morning, so morning exercise is recommended. Pay attention to how you fall asleep after an evening exercise class, aerobics, or a brisk walk, and you will realize that you have gone against your biological clock.

To summarize:

1. Trust your body; it knows best
2. The best time for exercise and larger meals is the morning and before noon
3. In the afternoon, arrange a little rest or less vigorous activity (even in the office, you can gently relax your body while seated)
4. Try to eat very little in the evening and at night, finishing your last meal about 2-3 hours before bed
5. If you are hungry at night, choose fruit, yogurt, or a cracker with a cup of caffeine-free herbal tea
6. · Get into the habit of going to bed at reasonable hours (22:00-23:00)

This is general news information and is not a substitute for personal advice from a doctor or dietitian.