Changing Your Clock: New Research Explores How Your Body Keeps Time

Researchers have learned that circadian rhythms -- the 24-hour cycles that keep time for your body -- are involved in sleep, weight gain, mood disorders, and a variety of diseases. They have begun to make remarkable strides in identifying the genes and neural pathways involved in regulating your internal clock.



In one study, it was found that circadian rhythms regulate metabolic processes involved in diet-induced weight gain, while others are exploring the connection between the role of temperature in regulating your daily cycles.



And in one surprising finding, researchers found that a single amino acid change in a protein triggers a chain of genetic events involved in internal timekeeping.



If this single modification is impaired, it could disrupt the cascade and serve as the underpinning of circadian rhythm-related ailments.

Sources:

Science Daily February 11, 2008



Dr. Mercola's Comments:

Everything in nature has a rhythm, and that includes your body. The ebb and flow of the ocean’s tide, the rising and setting of the sun, and the transition from one season to another all happen with comforting regularity. Your body, too, strives to keep its 24-hour cycle, or circadian rhythm, steady and even.



This is why most of us naturally feel like waking when the sun comes up, and sleeping when it’s dark. But your internal clock does much more than just help you nod off in the evening. Your body actually has many internal clocks -- in your brain, lungs, liver, heart and even your skeletal muscles -- and they all work to keep your body running smoothly by controlling temperature and the release of hormones.



Your heart rate, body temperature and hormone production vary with your personal internal clock. This, in turn, influences such things as:



~The easiest time to detect disease in your body

~The times when you’ll be less sensitive to pain

~The times when you’ll be more productive at work



Your circadian rhythm has evolved over many years to align your physiology with your environment. However, it is operating under the assumption that you are behaving as your ancestors have for generations: sleeping at night and waking during the day.



If you push these limits by staying up late at night, depriving yourself of sleep, or even eating at strange hours (such as at 2 a.m.), you are sending conflicting signals to your body. As a result, you body doesn’t know whether it should be producing chemicals to tell you to go to sleep, or gearing up for the beginning of your day.



Is Your Body Clock Making You Fat?



A disrupted body clock can wreak havoc on many areas of your health, including your weight.



For instance, losing sleep has been shown to raise levels of two hormones linked with appetite and eating behavior. More specifically, lack of sleep reduces leptin, a hormone that tells your brain there is no need for more food, and increases ghrelin, a hormone that triggers hunger.



On the other hand, your diet also impacts your internal clock, as what you eat sends your body signals about when to wake up and go to sleep. Your meals, which are typically at relatively consistent times throughout the day, also help to reinforce other time-setting activities.



This is one reason why it’s best not to eat a big meal right before you go to bed; this tells your body to get to work digesting your food during a time when it should be signaling you to go to sleep.



A Disrupted Circadian Rhythm May Cause Cancer



Aside from weight gain, if you throw your internal clock off kilter too much, chronic diseases like cancer can result.



In fact, the World Health Organization recently added overnight shift work to the list of probable carcinogens because it disrupts your biological clock. This disruption may influence cancer progression through shifts in hormones like melatonin, which your brain makes during sleep, and which is known to suppress tumor development.



Melatonin is an antioxidant that helps to suppress harmful free radicals in your body and slows the production of estrogen, which can activate cancer. When your circadian rhythm is disrupted, your body may produce less melatonin and therefore may have less ability to fight cancer.



The Importance of a Dark Night’s Sleep



Getting enough sleep during the night is only one part of the equation to keeping your body’s clock on schedule. You also need to sleep in a pitch-black room, because exposure to light during the night is damaging to your health.



For one thing, exposure to light during the night can reduce your melatonin levels and increase your risk of cancer. Getting exposed to light at varying times during the night also prevents your circadian rhythm from adjusting to a pattern, creating a state of permanent "jet lag."



This also activates your stress response and weakens your immune system, which is why irregular sleep cycles can lead to stress, constipation, stomach ulcers, depression, heart disease, and many other illnesses.



So please be sure to install some blackout drapes or shades in your bedroom, close the door, get rid of any nightlights or clock radio lights, and by all means, if you get up to go to the bathroom during the night, don’t turn the light on.



What Should You do if You’re a Night Owl?



Some of you are probably wondering what to do if you’re a night person, who simply feels best working and staying awake at night, and sleeping during the day.



Well, I would first suggest that you seriously think about whether you truly feel better this way, or if it is more a matter of habit, convenience or other exterior reason why you’ve adjusted your schedule this way.



Keep in mind that people have naturally been sleeping during the nighttime for many years, before the advent of electricity. This has been an important part of Ayurvedic medicine for over 5,000 years.



If you come to the conclusion that you simply must stay up at night, or if you work the night shift and can’t change it, you can somewhat counter the health effects by keeping to a schedule. This way, your body’s clock will eventually adjust to your sleep/wake cycle, and this is less damaging than if you constantly change shifts and expect your body clock to adjust (this is what happens to people who frequently travel long distances, have insomnia, or must change from day shifts to night shifts often).



Ultimately, your body is a phenomenal source of feedback. If it is telling you to stay up during the night, and you feel great afterward, then go for it as it is likely OK for you. The key is to honor the signals your body is giving you no matter what some “expert” tells you. My experience, however, is that it is very rare for most to be honestly and consistently in communication with their body's signals, and that is a powerful reason why so many get sick.



Keeping Your Body Clock Running Smoothly



The following tips can help to keep your circadian rhythm in its natural cycle:



Sleep in total darkness! If there is even the tiniest bit of light in your room it can disrupt your circadian rhythm and your pineal gland's production of the hormones melatonin and serotonin.

This is the “hidden” secret that most people tend to ignore. It was recently brought to my attention by my close friend, and highly knowledgeable chiropractor, Dr. Lloyd Fielder who told me that he never fully appreciated the power of this intervention. He recently installed blackout drapes in his bedroom and was shocked at how much better he felt -- it radically improved the quality of his sleep. Personally, I sleep in a room that is so dark, it’s even pitch black at noon.



Sleep when it’s dark outside and get up when the sun comes up. This is another largely ignored -- yet vitally important -- health principle. You should at least strive to sleep between 10 p.m. and 6 a.m. This means you should be in bed, with the lights out, by 10 p.m. and be up by 6 a.m.

Avoid working the night shift. It’s been linked to significantly lower levels of serotonin, which may cause sleep problems, anger, Depression and anxiety. If you currently work the night shift, I would strongly suggest trying to switch your hours, or at the very least not keeping the night shift for longer than a couple of months at a time (and giving your body a chance to readjust in between).



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