Scientific calcium supplementation cannot only focus on 'calcium supplementation' itself, it requires sufficient calcium intake, reasonable nutrition, and moderate exercise, "said Wu Yanyang, chief physician of Peking University First Hospital, at a press conference held by the National Health Commission today. Wu Yanyang said that the medium wave ultraviolet rays in light can promote the synthesis of vitamin D through the skin, and vitamin D can also promote the absorption and utilization of calcium. So, there is indeed a certain relationship between sun exposure and calcium supplementation. But it should be noted that more sun exposure is not necessarily better, especially in childhood. If one gets too much sun exposure and frequently suffers from sunburn, it can actually increase the risk of developing skin cancer in adulthood. So, scientific sun exposure is the most important thing. Wu Yanyang said that for adults, they can choose to expose the skin on their forearms appropriately when the sun is not so strong, for about 10 to 30 minutes. For children and adolescents, it is recommended to engage in no less than 2 hours of outdoor activities every day, which is very beneficial for their physical and mental health, especially for the prevention and control of myopia. When children engage in outdoor activities, they should avoid getting sunburned. They can wear sun hats, protective clothing, and use sunscreen products to prevent sunburn. Wu Yanyang reminds that sunbathing alone may not fully meet everyone's needs for vitamin D synthesis. For some people with darker skin tones, pigment particles in the skin can block ultraviolet rays from penetrating the skin, thereby affecting the efficiency of vitamin D synthesis. So these people may still be relatively deficient in vitamin D even after exposure to sunlight. There are also some situations, such as for people who stay indoors for a long time, lack outdoor activities, or have a habit of sun protection, as well as those who have been diagnosed with vitamin D deficiency in the hospital, they cannot simply rely on sun exposure to supplement vitamin D, but need to supplement it reasonably under the guidance of a doctor. (New Society)