一个人如果长期不接触阳光,得不到紫外线的照射,就容易患软骨病或佝偻病。这是因为人体的皮肤中,含的一种“T-脱氢胆固醇”的物质,这种物质通过阳光中的紫外线照射后,就变成了维生素D3。而维生素D3,能促进钙、磷在肠道的吸收。钙、磷是骨胳的主要成分。因此,晒太阳可以预防软骨病或佝偻病的发生。患维生素D缺乏症的人,往往是太阳光线照射得少之故。平常,一个人每天从饮食中吸收的维生素D约为2～3微克。人体的皮肤中,有一种胆固醇样 If a person does not long-term exposure to sunlight, UV exposure, it is susceptible to cartilage disease or rickets. This is because the body’s skin contains a “T-dehydrocholesterol” which, when irradiated by sunlight in the sun, becomes vitamin D3. The vitamin D3, can promote the absorption of calcium and phosphorus in the intestine. Calcium, phosphorus is the main component of the skeleton. Therefore, the sun can prevent the occurrence of rickets or rickets. Suffering from vitamin D deficiency, often less exposure to the sun’s rays. Normally, a person daily intake of vitamin D from the diet is about 2 to 3 micrograms. In the body’s skin, there is a cholesterol-like