Sunbathing in winter can promote blood circulation in the organism and improve the metabolism of the body’s organs and systems, and the time of sunbathing in winter should be determined according to age and physical condition. Regular exposure to the sun in winter has many benefits: first, it can help the body obtain vitamin D, preventing osteoporosis and rheumatoid arthritis and other diseases; second, it can enhance the function of the body’s immune system and increase the vitality of phagocytosis; in addition, it can also promote the body’s blood circulation and improve the metabolism of the organs. In the air environment as well as the temperature is appropriate, it is recommended that the physical condition of the elderly and infants and young children, in winter daily sunshine for about 1 hour. For young and middle-aged people with strong metabolisms, as well as adolescents in the growth and development period, the duration of sun exposure in winter can be extended appropriately, for example, about 2 hours of sun exposure per day. In winter, it is best to choose 6-10 hours and 16-17 hours to sunbathe outdoors, because the warm and soft infrared rays in 6-9 hours account for the peak, the human body can play a role in promoting blood circulation and metabolism; and 16-17 hours of sunlight in the ultraviolet A beam component is more, is the best time to reserve vitamin D in the body. However, for people who are sensitive to ultraviolet rays, they should choose sunbathing carefully.