维生素D功能很多。。

以前只是认为VD 对骨骼很重要，现发现VD对免疫系统，血管，抗癌都很重要。含VD丰富的食品不多：Some fish, such as salmon, tuna and mackerel, as well as fish liver oils are considered to be the best sources. Some vitamin D is also present in beef liver, cheese and egg yolks.