However, we must pay attention to science when sunbathing in winter. Experts point out that in a winter day, there are three most suitable periods for sunbathing. The first stage is from 7: 00 to 9: 00 in the morning. During this period, the infrared rays of sunlight are dominant and the ultraviolet rays are low, which makes people feel warm, comfortable and soft, and can promote blood circulation and remove blood stasis. The second stage is 9: 00 am 9:00- 10/0, and the third stage is 4: 00 pm-5: 00 pm. In these two periods, the A-beam of ultraviolet rays has the upper hand, which can promote the absorption of calcium and phosphorus in the intestine, promote the normal calcification of bones and enhance physical fitness.
What needs to be pointed out here is that no matter what season, it is best not to bask in the sun for a long time from 10 to 4 pm, especially from 12 to 4 pm. Because at this time, the ultraviolet rays in the sun are B-beam and C-beam, which will cause harm to the skin and may also cause other diseases. Sunbathing for more than 40 minutes every day is good for your health.