At 6:00- 10 in the morning, the sunlight has strong infrared rays and weak ultraviolet rays, which can promote blood circulation and remove blood stasis. From 4 pm to 5 pm, it can promote the absorption of calcium and phosphorus in the intestine, enhance physical fitness and promote normal calcification of bones. However, the sunshine time is longer in summer, and the heat wave is rolling at 4-5 pm, so the sunshine time can be slightly delayed.
These are only for ordinary people, not including pregnant women, children and the elderly. These special people need more calcium and pay more attention to sunbathing.
1, pregnant women: need to bear the calcium needs of two people. It is enough to bask in the sun for half an hour every day in summer, and not less than 1 hour every day in winter. You can't stay indoors all day, because your body is inconvenient.
2. Children: The need of development makes them need a lot of calcium, and they are most vulnerable to calcium deficiency. So starting from two months, you should go outdoors to bask in the sun every day. 9 ~ 10 in the morning and 4 ~ 5 in the afternoon are suitable time to go out. The time to receive sunlight can be gradually extended from the first ten minutes to one hour. When the weather is not too hot, you can bask in the sun and stay in the shade for a while. Don't be in the sun directly in summer, because scattered ultraviolet rays can also be received in the shade. Old people: it is also the key group of calcium supplementation. You can sunbathe before 9 am and after 4 pm, but you'd better not go out alone to sunbathe. If you fall asleep in the pleasant sunshine, you may catch a cold. Find a few companions and talk while walking. They are easily exposed to ultraviolet radiation.
In winter, due to the seasonal weakening of the ozone layer and the strengthening of ultraviolet rays in the sun, it is easy to bring different degrees of harm to people's health. Therefore, we should also pay attention to the scientific choice of time when sunbathing in winter. According to scientific research, in winter, there are three periods suitable for sunbathing:
The first stage is from 6: 00 am to 9: 00 am, during which the sunshine is mainly warm and soft infrared rays, and the ultraviolet rays are relatively weak. Infrared ray has high temperature, which mainly plays a role in warming the human body, can warm the body, promote blood circulation and metabolism, and enhance human vitality.
The second and third stages are 9 ~ 10 in the morning and 4 ~ 5 in the afternoon respectively. The characteristics of irradiation in these two periods are that there are many components of beam A in ultraviolet rays, which is a good time to store vitamin D, a "sunshine vitamin" in the body; At the same time, it can also promote the absorption of calcium and phosphorus in the intestine, enhance physical fitness and promote normal calcification of bones.