On Monday, the Nobel prize was awarded to three physiologists who first discovered that cells inside organisms change their function based on the time of day. These physiologists spent decades studying how the circadian rhythm operates inside plants, animals and people. We now know that when we see daylight, the hypothalamus in the brain tends messages to the cells and systems in the body to alter the way they function. The clock genes inside our cells change the protein pathways of that cell. That’s why your liver, your digestive track, your brain, your circulatory system are doing different things at night than they do during the day. Coincidentally, a feature in this month’s Scientific American summarizes many of the discoveries that chronobiologists like these have made in recent years and it asks the provocative question, “Is your schedule killing you?”
After several decades of clinical practice with tens of thousands of patients, my answer to that question is: Yes. Although it’s well known that the 15% of American shift workers are more prone to metabolic disorders, depression and heart disease, most Americans function as part-time shift workers by virtue of the schedule we impose on ourselves. We stay up late watching TV or working on laptops. We eat late dinners and snack after dinner. Yet our alarms sound at the same early hour every work day and we drag ourselves out of bed without the adequate rest that our brains and digestive systems need to function properly. Sleeping in on the weekend is no solution. Chronobiologists call this habit “social jet lag” and say that it further confuses the body’s systems. Going to work on Monday morning after a weekend of sleeping and eating late is sort of like going to work after flying from New York to California and back over a weekend.
The circadian rhythm is a real force in our lives and we ignore it at our peril. My patients come to my clinic in Santa Cruz, California because they can’t lose weight. They have no energy and can’t quite get to sleep at night once they put the smartphone away and shut off the TV. They think it’s because they have no willpower to adopt the healthy habits they know they need. In reality, it’s because they are ignoring the clock genes that rule their physiology. Chronobiologists know that the digestion is strongest in the first half of the day and weakest after dusk. I tell my patients to eat their largest meal at noon and eat a very light dinner in the early evening. After that, they should eat nothing because the digestive tract needs at least 10 hours of rest overnight to conduct repairs and produce necessary hormones. By eating a lighter and earlier dinner, and by shutting off electronic stimulation after 8:30 at night, patients find that many of their health problems disappear. Finally, they can fall asleep at a reasonable time and wake up refreshed. Finally, they can lose weight. Their blood work improves dramatically. Other ailments including heartburn, headaches, snoring, and minor aches and pains go away as well. When I add 20 minutes of vigorous exercise first thing in the morning, their moods rebound along with their natural focus at work. I didn’t invent these solutions. They are based on Ayurvedic medical practices that date back 5,000 years. Ancient scholars understood that man is part of nature, and like the natural world he functions by the light of the sun.
Fortunately, western medicine is catching up to these ideas with fascinating descriptions about how daylight interacts with the brain and how the hypothalamus in the brain communicates with clock genes all over the body to change the way the body functions all day and night.
For forty years the research of these Nobel laureates has been the leading edge of chronobiology. They have been telling us that timing is everything in physiology. The old adage “you are what you eat” no longer holds. You are also when you eat, when you sleep and when you exercise. They have been telling us that most if not all living organisms have these clock genes that rule nutritional intake and the rest and repair of cells. Of course, birds and plants have no choice but to take in nutrients by the light of the sun and rest when it’s dark. People are different in that we have choices. Maybe too many choices. We have cupboards full of nonperishable foods and 24-hour connectivity to distract us into the wee hours. My patients have found that by breaking these simple habits, they become thinner, healthier and more energetic.
There is some evidence that their brains benefit as well. In his best-selling book “The End of Alzheimer’s,” Dale Bredesen argues for these same lifestyle changes as a means to stave off or reverse cognitive decline. Getting to sleep on time and giving your digestive tract at least 10 hours of rest every night also reduces inflammation—the other national epidemic—which is a leading trigger for age-related cognitive issues. Good nutrition helps. So does exercise. But the missing piece is setting a healthy daily schedule that supports the body’s powerful circadian rhythm.
Bredesen is telling readers the same things that chronobiologists have been urging for years. And it’s the same thing I tell my patients as well. You can’t fix your health until you fix your daily schedule. Eat earlier in the day and unplug at night and your life will change for the better.