When there is a deficiency of vitamin D, it can lead to rickets, so parents should pay attention to providing their children with an adequate amount of vitamin D in a timely manner. There are two sources of vitamin D. Which foods can provide vitamin D.
Natural vitamin D comes from animals and plants. For example, the liver of marine fish contains a relatively high amount of vitamin D. After it is extracted, it is made into cod liver oil, which can be used to prevent rickets. Fish roe, egg yolks, and dairy products also contain small amounts of vitamin D3. Ergosterol in plants (fresh vegetables) is converted into ergocalciferol, or vitamin D2, after exposure to ultraviolet light. Additionally, yeast and dried vegetables also contain vitamin D2. All of the above are collectively referred to as exogenous vitamin D, which is absorbed into the body through the digestive tract.
The other source of vitamin D is synthesized by the body itself and is called endogenous vitamin D. It is formed when 7-dehydrocholesterol in the subcutaneous tissue of human skin is directly exposed to ultraviolet rays from sunlight, converting it into cholecalciferol, or endogenous vitamin D3. This is actually the main source of vitamin D for the human body. Therefore, in addition to getting vitamin D from food, children should also engage in outdoor activities and have more exposure to sunlight. Do not stay indoors for long periods, and do not sunbathe through glass, because glass can block the ultraviolet rays in sunlight, rendering it ineffective. At the same time, it is also necessary to supplement with medications, such as cod liver oil, vitamin D preparations, and so on.