Sunbathing is to use the light of the sun to exercise, which can achieve the purpose of enhancing the ability to resist diseases.
Sunlight contains two kinds of light, one is infrared and the other is ultraviolet. Infrared rays, also called thermal rays, have the wavelength of light, which can make people feel warm, dilate blood vessels, promote blood circulation and enhance resistance. Ultraviolet light has short wavelength, high energy and strong chemical stimulation, which can convert 7- dehydrocholesterol in skin into vitamin D, which can promote the absorption and utilization of calcium and phosphorus and prevent rickets. Ultraviolet rays can also activate the whole body function, enhance metabolism and stimulate the hematopoietic function of bone marrow. At the same time, ultraviolet rays can also kill bacteria and viruses and enhance the skin's resistance.
Sunbathing should pay attention to the following points:
1. The content of ultraviolet rays in sunlight is related to geographical conditions and climate. As far as Beijing is concerned, ultraviolet rays began to decrease in late autumn and early winter, and gradually increased in late winter and early spring, with the fastest increase in March and July and maintained at a certain level from August to September. Apply sunscreen before sunbathing in summer. The ultraviolet content in the sun will also change during the day. 10 sunbathing should be avoided in principle from morning to 2 pm.
2. Sunbathing should be naked, wearing a sun hat, sunglasses, lying on your back, prone, etc. And try to increase the contact area between the skin and the sun.
Three. Time should be gradual, the first time should not exceed five minutes, and then increase by one minute every day, up to fifteen minutes.
4. Choose a clean and sheltered place, and be careful not to catch cold.
5. carefully observe the reaction during exercise. If you find excessive sweating, pale face, headache, loss of appetite, skin allergies, etc. You should stop exercising in time and analyze the reasons.
6. Exercise must be regular in order to enhance the adaptability of the body.
Seven. People with severe anemia, hyperactivity disorder, tuberculosis, intestinal dysfunction, infectious diseases, fever and other diseases can't bask in the sun.
But be careful to avoid exposure!
Sunbathing, once regarded by westerners as the latest fashion, has aroused the deep thinking of health care doctors because of the sharp increase of skin cancer. Studies have shown that overexposure is not an enhancer of health, but a chronic killer of human beings. Therefore, health medical experts warn people that sunbathing should be moderate and not excessive.
Five years ago, Maureen Reagan first found a spot on her right thigh. She didn't care too much at that time. It was not until Spot looked like "running water" that she realized it was time to see a doctor. That nasty thing turned out to be a very serious malignant melanoma. So, she had a resection. After a year of painful treatment, Maureen finally got rid of the shadow and became cheerful and optimistic. But this spring, doctors found cancer in her groin, right arm, liver and ribs, and cancer cells had invaded her brain. Despite the most challenging treatment, Maureen died at home last week.
To the surprise of doctors, the incidence of skin cancer is on the rise in the United States. The American Cancer Society estimates that about 565,438+0,400 people will be diagnosed with melanoma, and 7,800 of them will die of this disease.
A large number of direct and indirect evidences prove that melanoma patients almost all have a history of intense sunlight exposure. Maureen belongs to the kind of person who wears sunscreen all over her body and becomes a sunlight reflector when exposed to the sun. When sunbathing and tanning are becoming more and more fashionable, the incidence of melanoma is also increasing rapidly around the world.
Dr. Kathy Fields, a dermatologist in San Francisco, pointed out that people thought that sunscreen applied to their bodies had magical effects and could resist the baking of big fireballs in the sky, but in fact it was far from it. Sunscreens such as sunscreen oil and sunscreen may help prevent skin from tanning, but they may increase the incidence of skin tumors because these sunscreens do not work.