What are the unexpected conflicts in good sleep according to the greatest expert in the genetic regulation of sleep

Phyllis Zee is a recognized leader in the field of sleep, particularly in the area of circadian rhythm science and medicine. She is director of the Center for Circadian and Sleep Medicine, Head of Sleep Medicine in the Department of Neurology, and Professor of Neurology at Northwestern University's Feinberg School of Medicine in Chicago, Illinois.

She is the founder of the first circadian medicine clinic in the United States. Department of Education that provides innovative approaches to diagnose and treat people with circadian rhythm disorders of sleep and wake. Her research focuses on the effects of age on sleep and circadian rhythms, the genetic regulation of circadian sleep disorders, and behavioral interventions to improve sleep and performance. His laboratory is currently studying the effects of circadian sleep-based interventions, such as exercise, bright light and fast eating schedules, on cognitive, cardiovascular and metabolic functions and their potential to delay cardiometabolic aging and neurodegeneration.

His most recent study revealed that falling asleep with television or the glow of an intrusive light outside the window can be harmful for good sleep. “Light pollution sneaks in at night in many ways, and research shows that it is not good,” he says in an exclusive telephone interview for Infobae Phyllis Zee, “in particular for our metabolic health.”

- What are the effects after just a bad night's sleep?

-To find out, with our team we designed a small studio with 20 people. They all spent the first night sleeping in a mostly dark room. Then, the second, half of them slept in a moderately well-lit space. With enough light so you can see your way, but not enough to read comfortably. While the subjects were asleep, we ran some tests. We recorded brainwaves, measured heart rate, even drew blood every few hours. Then, after waking up, the participants received a large dose of sugar. We found some clear differences. Those who slept with light had a continuously elevated heart rate compared to their first night in the dark room. And in the morning, they also had more trouble getting their blood sugar level back to normal.

It's what you call a state of insulin resistance, right?

-That's right, which can lead to many other conclusions. What surprised us was that these physiological changes occurred even though real sleep was not really disturbed. In fact, people generally said they slept well. It's almost like the brain and heart knew the lights were on, even though the individual was sleeping.

- What other conclusions did you come to?

-We detected this relatively small amount of light hitting the eyelids was not enough to suppress the hormone melatonin, which is important for sleep, but it seems that it was enough to change the nervous system to a more alert and activated state. It wasn't as dramatic, as strong as being awake. But on the other hand, it's not something you want that to happen when you're trying to get a good night's sleep. It is a very important example of how even exposure to relatively dim light in our home environment can alter our sleep and wake cycle. Scientists have learned a lot in recent decades about the body's light detection system and how inadequate exposure to light at night can be harmful.

-It tends to bring animals to a pro-inflammatory state. It can have profound effects on metabolism and cardiovascular function, among others. But these types of sleep studies can be difficult to perform on humans. Beyond our small study, this allows us to ascertain the suspicion that the negative effects will increase as soon as we can deepen these investigations.

-People think that while they fall asleep it has no physiological effects, but that is not true, according to their conclusions.

- Clearly not. If you are chronically exposed to this kind of thing, you will increase your risk of chronic diseases such as insulin resistance, diabetes, and other cardiometabolic problems. For example, a five-year observational study of more than 40,000 women found that having a light or television on while they slept was associated with an increased risk of gaining more than 4.5 kilograms. Added to this is a high heart rate, increased insulin resistance and an imbalance in the sympathetic and parasympathetic nervous systems.

- What recommendations can you give us to deal with these disorders caused by light during sleep?

- It would be ideal to turn off all lights before going to sleep, close curtains and blinds and wear a sleep mask if possible. If possible, make sure you start dimming your lights at least an hour or two before going to bed to prepare your sleeping environment. In addition, all blue lights such as those on mobile phones should be banned.

-In many countries time zones are adapted to periods of greatest illumination. Have you and your team seen health benefits in this regard?

- Many scientific studies have already shown that seeing the light in the morning is essential for health, and without it we have more cancer, diabetes and obesity. For most of us, moreover, waking up in the dark is difficult for our internal watches and our sleep. Throughout the world, debates have spread and the decisions of specialists have been inclined to put an end to time changes twice a year. Some times are better than others, and setting our watches in a way that makes us sleep less throughout the year would be bad for our health. The consequences of this type of sleep and light disruption are very serious. Shift work can increase the lifelong risk of cancer by 70%. Playing with the clock in smaller amounts is also important: the best numbers say that getting people to wake up an hour earlier could lead to 10-20% more cancer. That is a big disconnect between science and politics that seeks to improve public health. In general, those of us who study cicardian cycles agree that the scientific evidence currently available indicates that the installation of perennial standard time (winter time) is the best and safest option for public health. It will be healthier than daylight saving time in terms of sleep, heart function, weight, cancer risk and alcohol and tobacco use.

- Could you summarize what are the cicardian cycles that are your focus of research?

-We all have an internal clock that produces circadian rhythms, intrinsic rhythms that mark a time of approximately 24 hours. The cycles of light and dark do not drive them; instead, these rhythms are generated at the molecular level. This circadian clock system exists in every cell of the human body and is regulated by a central clock genetic mechanism. There are also more than 10 clock genes that reside in the nucleus of cells and produce proteins that determine whether a person is a “night owl” or a “morning lark”. How quickly these proteins degrade in the cytoplasm determines whether it will be an owl or a lark. So if it's an owl, it's because its genetic clock system is taking a little longer than the 24-hour cycle. If you're a lark, your watch will probably go a little faster. That's why larks get up early, because they finished that circadian cycle, that circadian molecular cycle, a little faster than the rotation of the earth on its axis around the sun.

-Your team developed a blood test capable of identifying accurate times of people's internal clock compared to external time, what were the conclusions?

-The test, called Time Signature, requires only two blood draws. Previously, such accurate measurements required a costly and laborious process of taking samples every hour for almost an entire day. This is a first step in providing what I call a biomarker, a time-based biomarker, for circadian time, and it's not just for sleep. The blood test could advance personalized medicine and help doctors determine the best time of day for a person to take certain medications, such as for blood pressure and others that target the genes of the clock. We can maximize not only the effectiveness, but also reduce the side effects of medications.

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