But in fact, sunbathing is very beneficial to people's health. Sunbathing can stay away from diseases more than taking medicine and nutrition.
Research shows that sunbathing can make people feel happy. There is a neurotransmitter called serotonin in the brain, which can bring happiness and pleasure to people. Sunbathing can improve the turnover rate of serotonin in the brain and make people feel happy. Adequate sunshine can also promote the secretion of adrenaline and thyroid hormone, which helps to improve bad mood. Therefore, psychologists often advise patients with depression to go out to bask in the sun, which will help the recovery of depression.
Emotion will affect people's health, often having a happy mood can delay aging, while negative emotions can cause some diseases. The digestive system is a good emotional expression device. Many people will be so angry that they have a stomachache and can't eat, just because anger will excite sympathetic nerves, promote gastric acid secretion and damage gastric mucosa.
In addition to gastrointestinal diseases, being in a bad mood can cause many other systemic diseases. So the good mood brought by sunbathing can avoid many diseases and keep healthy.
Sunbathing can also enhance human immunity and make the body less sick. Regular sun exposure can increase the proliferation of monocytes, promote the transformation of monocytes into macrophages, and enhance the function of immune cells such as macrophages in the body. When viruses and harmful bacteria invade the body, the activities of immune cells can devour and kill these bacteria and viruses, thus preventing immune diseases such as viral colds.
In addition, regular sun exposure can also prevent cardiovascular diseases. Regular sun exposure helps to maintain a high level of vitamin D in the body, which can reduce the occurrence of inflammation in the body, thus playing a role in protecting blood vessels. Most cardiovascular diseases are initially caused by vascular wall injury, and the next step of vascular wall injury is inflammation, which leads to blood circulation problems.
Vitamin D can activate immune cells to play a role, reverse the damage of cardiovascular system, better prevent the hardening and blockage of cardiovascular system, maintain the elasticity of blood vessels and smooth blood flow, and play a role in preventing diseases such as hypertension and coronary heart disease. [ 1]
Cardiovascular disease is the most common chronic disease in middle-aged and elderly people. Regular sun exposure can reduce the risk of heart disease and myocardial infarction. With a healthy body, life expectancy will naturally be extended.
In addition to cardiovascular diseases, osteoporosis is also a problem faced by middle-aged and elderly people. Sunbathing can play a role in preventing osteoporosis.
It is reported that more than 70 million people in China suffer from severe osteoporosis, and one of the causes of osteoporosis is insufficient sunshine.
First of all, we need to know how osteoporosis appears. Human bones are "alive" and will be continuously absorbed and decomposed. With the increase of age, the metabolic capacity of the body decreases, the formation of new bones decreases, and excessive calcium loss leads to the decrease of bone density and the increase of bone brittleness, which eventually leads to osteoporosis. Bone metabolism needs the participation of calcium. When the calcium content in the body is insufficient, it will affect the synthesis of bones. In addition, in order to maintain blood calcium concentration, bones will release some calcium into the blood, thus accelerating the occurrence of osteoporosis.
The main way for people to get calcium is food. After calcium-containing food enters the gastrointestinal tract, calcium ions will enter the blood through ion channels on the intestinal mucosa. Vitamin D can increase the calcium channel of intestinal mucosa, increase calcium absorption, improve blood calcium level, and contribute to the deposition of calcium in bones.
Under the irradiation of sunlight, it is mainly divided into infrared rays and ultraviolet rays. Ultraviolet rays can increase the transformation of active vitamin D in the body, thus achieving the effect of calcium supplementation.
In addition, osteoblasts are mainly divided into osteoblasts and osteoclasts. As the name implies, the main function of osteoblasts is to promote bone formation. Osteoclasts are mainly responsible for the destruction and decomposition of bones. Vitamin D can promote the formation of osteoblasts, increase the hardness of bones and improve osteoporosis.
In addition, menopausal women are more likely to suffer from osteoporosis, because the estrogen level in the body is greatly reduced before and after menopause, which can not effectively inhibit osteoclasts, leading to accelerated bone destruction and dissolution, and accelerating the formation of osteoporosis.
The bone mass of human body continues to decline after reaching its peak at the age of 30. Poor living habits such as lack of outdoor activities and unbalanced diet will promote the formation of osteoporosis.
Some people will think, "Since vitamin D can promote the absorption of calcium, why don't I eat more foods supplemented with vitamin D?" . However, it is not enough to supplement vitamin D to promote calcium absorption. Because only 10% of the active vitamin D in the human body comes from food, most of the others are transformed by sunlight, so food supplement can't replace sun exposure.
More sunshine for infants can also prevent rickets and rickets, more sunshine for teenagers can promote bone development, and more sunshine for the elderly can prevent osteoporosis and reduce the probability of fractures. [2]
Sunbathing can not only improve bone condition, but also promote brain development and exercise brain ability.
Regular exposure to the sun helps to promote the intellectual development of children's brains and delay the intellectual decline of the elderly. This is also inseparable from the role of vitamin D. Ultraviolet rays in sunlight can convert 7- dehydrocholesterol in human skin into vitamin D3, which is an active vitamin.
Vitamin D can promote the growth and development of nerve cells, promote the division of nerve synapses, and make nerves and muscles respond to external stimuli. Studies have shown that vitamin D is related to the synthesis of various brain proteins and plays a role in protecting nerves. If the body lacks vitamin D, it will aggravate the damage of nerve cells and lead to the occurrence of nervous system diseases.
Vitamin D can increase the level of glutamic acid in the brain, which can maintain brain function, provide energy for the brain and protect the nerve center and cerebral cortex. The cerebral cortex can maintain the normal conduction function between nerves, improve people's cognition of things, and support people's functions such as language, sports and mental activities.
Vitamin d can also promote the excitement of hippocampus. Alzheimer's disease usually occurs in the elderly, which is the result of the degeneration of hippocampus. The hippocampus is mainly responsible for the formation and storage of memory. The degeneration of hippocampus will lead to memory loss and cognitive impairment. Studies have shown that the lack of vitamin D will reduce the neuronal network around the hippocampus, make the neurons in the hippocampus lose contact, and eventually lead to the decline of cognitive function.
For growing children, this period is the golden stage of brain development. More sun exposure and vitamin D supplementation can not only prevent rickets, but also promote the development of brain neurons and improve children's intelligence and learning ability. Doing more outdoor activities can also cultivate children's lively and cheerful personality and improve their perception of nature.
For the elderly, the brain nerves will age with age. More sun exposure can slow down the decline of cranial nerves, delay the decline of memory, and play a role in preventing Alzheimer's disease.
In addition, sunlight can stimulate the secretion of dopamine, which can prevent the axial length from becoming longer and reduce the risk of myopia.
Sunbathing is also learned. How can we maximize its benefits?
Sunbathing is also a "technical job" People of different ages have different ways to sunbathe. Only by mastering the skills of sunbathing can we better maintain our health.
In a day, the best time to bask in the sun is before 10 in the morning and after 4 pm. Mild sunshine in these two periods can not only supplement vitamin D, promote metabolism, but also prevent the skin from being sunburned by too strong ultraviolet rays.
It is enough for infants to bask in the sun for about 1.5-30 minutes every day. Teenagers can be appropriately extended to 1-2 hours a day to promote the growth and development of the body. Middle-aged and elderly people can spend 30-60 minutes in the sun every day. Sunbathing time can be shortened in summer. Pay attention to keep warm when sunbathing in autumn and winter, and don't blow air conditioning to avoid catching a cold.
Exposing your back can enhance your immunity. There are many immune cells under the skin of human back. Sunbathing can activate them, help to enhance immunity and help to absorb calcium.
More contact with the top of the head can promote hair growth. Sunlight overhead can help stimulate hair length and help hair grow; It can also promote children's brain development and help babies with closed front fontanel.
Drying your palms helps you sleep. People's palms rarely bask in the sun, so basking in the palms helps to relieve fatigue, improve insomnia and improve sleep quality.
Dry your legs more to prevent cramps. Many people have "old cold legs". More sunshine on your legs can promote blood circulation and help drive away the cold in your legs. More sunshine on the legs can accelerate the absorption of calcium by the bones of the lower limbs, effectively prevent cramps in the legs and eliminate fatigue in the legs.
Studies have shown that glass can block ultraviolet rays in the sun, and sunbathing through glass will affect the effect of ultraviolet rays promoting the formation of vitamin D, which will greatly reduce the effect of sunbathing.
Try not to wear white clothes when you are in the sun, because white clothes will reflect short-wave ultraviolet rays that are very destructive to your face and hurt your skin.
Sunbathing can be said to be the simplest and most economical way to keep fit. Although it is good for your health, it is not enough. Too much sunlight will harm your skin and increase the risk of skin cancer. If you are outdoors for a long time, you can properly apply sunscreen and take sunscreen measures. Remember to drink plenty of water after sunbathing, replenish the evaporated water in the body, and eat more fruits and vegetables to inhibit the production of melanin, which can prevent the skin from turning black to some extent.