Exposure to bright light synchronizes our brain's central circadian clock, while proper meal timing helps synchronize the timing of different clock genes in the rest of our body.
One of the most important advances in recent years has It has been the discovery of “peripheral clocks”. we have acquaintance for decades on the central clock, the so-called suprachiasmatic nucleus. It is located in the middle of our brain, just above where our optic nerves cross, allowing it to respond to day and night. Now we also know that there are are semi-autonomous clocks in almost all the organs of our body. Our heart works according to a clock, our lungs work according to a clock and so do our kidneys, for example. In fact, up to 80 percent of the genes in our liver are voiced in a circadian rhythm.
Our entire digestive tract is, also. The rate at which our stomach empties, the secretion of digestive enzymes, and the expression of transporters in our intestinal lining to absorb sugar and fat circulate 24 hours a day. So does our body fat's ability to absorb extra calories. The way we know these cycles are driven What happens with local clocks, instead of being controlled by our brain, is that you can take surgical biopsies of fat, put them in a Petri dish, and watch them continue to tick.
All this talk about the clock isn't just biological curiosity. Our health may depend on keeping them all in sync. “Imagine a child playing on a swing.” Imagine yourself pushing, but you get distracted by what's going on around you on the playground and stop paying attention to the moment of the push. Then, you forget to push or you do it too early or too late. What happens? Being out of sync, the rolling becomes erratic, slows down or even stops. That's what happens when we travel across multiple time zones or have to work the night shift.
The “pusher” in this case is the light signals that fall on our eyes. Our circadian rhythm is meant to get a “boost” from bright light each morning at sunrise, but if the sun rises at a different time or we are exposed to bright light in the middle of the night, this can throw off our cycle. synchronize and leave us feeling in a bad mood. That's an example of a mismatch between the external environment and our central clock. Problems can also arise from a misalignment between the central clock of our brain and the clocks of all the other organs in our body. An extreme example of this is a remarkable set of experiments suggestion that even our poop can suffer from jet lag.
As you can see below and at minute 2:31 of my video. How to synchronize your central circadian clock with your peripheral clocksour microbiome seems have your own circadian rhythm.
Although bacteria decline where the sun doesn't shine, there is a daily swing in both bacterial abundance and activity in our colon, as you can see in the graph below and at 2:43 in my video. Interesting, but who cares? We should all do it.
Look at this: if you put people on a plane and fly them to the other side of the world, and then feed their droppings to mice, those mice get fatter than mice fed feces before the flight. The researchers suggest that the fattening flora was a consequence of a “circadian misalignment.” In fact, several lines of evidence now to imply “chronodisruption,” the state in which our central and peripheral clocks are out of sync, as playing a role in conditions such as premature aging and cancer, as well as range to others such as mood disorders and obesity.
Exposure to bright light is the synchronizing button for our central clock. That she drives Do our internal organs clock that are not exposed to daylight? Food intake. That is why the timing of our meals can be so important. Researchers remote all external synchronization cues by keeping study participants under constant dim light and found that they could effectively decouple central from peripheral rhythms simply by changing meal times. They took blood samples every hour and biopsies of the subjects' fat every six hours to demonstrate the resulting metabolic disorder.
Just as morning light can help synchronize our brain's central clock, morning meals It can help synchronize our peripheral clocks in the rest of our body. Skipping breakfast disrupts the normal expression and rhythm of these clock genes, coinciding with adverse metabolic effects. Fortunately, they can be reversed. Carry a group of people who usually do not eat breakfast and have them eat three meals at 8:00 am, 1:00 pm and 6:00 pm, and their cholesterol and triglycerides improve, compared to eating meals five hours later, at 1 :00 pm, 6:00 pm and 11:00 pm. There is There is also a circadian rhythm for cholesterol synthesis in the body, which is also “strongly influenced by food intake.” This is evidenced by the 95 percent drop in cholesterol production in response to a single day of fasting. That's why a change in meal times of just a few hours can result in a 20 point drop in LDL cholesterol, thanks to eating earlier, as you can see below and at 5:00 in my video.
If light exposure and meal timing help keep everything in sync, what happens when our circumstances prevent us from following a normal diurnal cycle? We will find out in The metabolic damage of night shifts and irregular meals. If you're just getting into the series, be sure to check out the related posts below.