Шаргородская Анна Витальевна
Врач акушер-гинеколог, эндокринолог, специалист УЗ диагностики

SLEEP AND HORMONES. Part I: Why is it important to sleep well?

Numerous studies over the past decades have shown that sleep plays a key role in maintaining the health and normal functioning of our body.
In children, good sleep is known to promote healthy growth and development. However, the processes of renewal and growth of cells do not stop during a person’s life. At any age, a sufficient amount and quality of sleep is necessary for the normal functioning of the immune system and endocrine organs, the regulation of metabolism and ensuring physical and mental health. When a person gets enough sleep, it is easier for him to concentrate, make decisions, learn new skills and be creative.

In 2017, Jeffrey Hall, Michael Rosbash, Michael Young won the Nobel Prize in Physiology or Medicine for discovering the molecular mechanisms underlying circadian rhythms – the biological “clock” responsible for the body’s response to change day and night. This event served as a new impetus for the study of biorhythms of animals and humans, and even the emergence of a new field of science – chronobiology.

It turned out that the change of day and night is fixed in living organisms at the genetic level, and these “clocks” that perceive external signals – primarily light, work in all cells that have a nucleus. So, the importance of the correct settings of our biological clock for the adequate functioning of the body cannot be underestimated.

Light and its absence are the main, though not the only, regulators of circadian rhythms. Cold blue light from office lamps, computer screens, TVs and smartphones breaks these rhythms. As a result, the body “thinks” that daylight hours are in full swing. Red and green light also negatively affect the course of the internal clock.

If you watch serials at night, have a late and heavy dinner, work the night shift and go to bed at dawn, the coordinated work of genes and circadian rhythms is disrupted. Some metabolic processes start later than usual, and some stop completely.

Chronic neglect of your biological rhythms disrupts the process of falling asleep, causes increased cravings for sweets and fast food (the body tries to compensate for the lack of energy), leads to mood swings during the day and a surge of negative emotions, increases the risk of depression and other neuropsychiatric disorders.

Poor sleep quality or insufficient sleep can disrupt hormonal balance. Almost every hormone in the body is produced in response to our circadian rhythm. Healthy sleep is especially important for the regulation of hormones such as cortisol, estrogens and progesterone, the “hungry trio” – insulin, leptin and ghrelin, thyroid hormones, melatonin and growth hormone.

In Tame Your Hormones, Sarah Gottfried, MD (USA), writes, “Bad sleep, if ignored, will cause you to fall down the hormone ladder.” And this is true no matter how old you are.

“HUNGER HORMONES” (insulin, ghrelin, leptin)

Compared to previous decades, today’s adults and children sleep less. Most serious epidemiological studies point to this factor as significant in the development of obesity and diabetes mellitus (DM).

Sleep restriction leads to a violation of glucose uptake and a decrease in insulin sensitivity (the development of insulin resistance), an increase in cortisol levels in the evening and at night, as well as an increase in the concentration of ghrelin in the stomach wall against a background of a decrease in leptin levels (these hormones are responsible for how the food that we eat is used for energy and storage in our body), which leads to increased feelings of hunger and appetite. These changes contribute to eating disorders, late eating and nocturnal trips to the refrigerator, and as a result, weight gain and the development of DM.

Cortisol is known as the stress hormone produced by the adrenal glands. It helps regulate other hormones in the body. Normally, the release of cortisol in the evening hours (19-20 hours) is minimal, and the peak occurs in the pre-morning hours of awakening. The morning peak of cortisol release activates all other hormones, bringing the body into the “active phase”.

In sleep disorders (insomnia), cortisol levels in the evening and at night are higher than necessary. In the morning, cortisol is also more than required. Chronic lack of sleep leads to constant excitation of the nervous system, is perceived by the body as chronic stress and leads to the depletion of its reserve capacity. The so-called chronic fatigue syndrome develops, which in turn disrupts the immune system, reduces the body’s resistance to infections, and contributes to the development of arterial hypertension and cardiovascular diseases.

Cortisol production disruption can also lead to thyroid suppression and an imbalance between estrogen and progesterone, hormones that play an important role in maintaining the health of the reproductive system.

MELATONIN is a hormone produced by the pineal gland (pineal gland) that helps regulate the body’s circadian rhythms to

Our sleep was calm and deep.

With the onset of twilight, melatonin levels begin to rise, reaching their maximum value from midnight to 4-5 a.m., and then decreasing. If you are surrounded by too bright light in the evening, melatonin will not be produced in the right amount. Melatonin does not induce sleep per se, its effect promotes certain changes in the body that precede falling asleep. For example, body temperature decreases, which reduces the level of activity and alertness.

The functions of melatonin are not limited to the regulation of sleep. It controls over 500 genes in the body, including genes involved in the immune system. It has an antioxidant effect, protecting our cells from damage, is involved in the regulation of the thyroid gland and thymus, and has an anti-stress effect on the body. The hormone reduces cortisol levels and stimulates the production of endorphins.

GH, also known as somatotropin, promotes healthy growth and development and plays a vital role in protein production and synthesis, muscle development, glucose, lipid and protein metabolism, and immune system function.

The peak of its production occurs at the same intervals as that of melatonin. Growth hormone deficiency contributes to the accumulation of fat in the abdomen, reduces recovery opportunities after injury. With insomnia and growth hormone deficiency, you will never be able to lose weight.

The good news is that a broken biological clock can be repaired. How to do it and what to pay attention to read in CONTINUED…