Here is what Registered Dietician, Whitney English, says about including vitamin D as part of a vegan nutrition plan:
Vitamin D is a fat-soluble vitamin found mainly in fish and eggs.
It’s responsible for regulating calcium absorption and use in our body, and helping to prevent osteoporosis. Vitamin D is also involved in immune function and cell growth, and emerging research shows it may play a role in cancer prevention.
Our body can actually make vitamin D from cholesterol in our skin using sunlight. However, because of the use of sunscreen and the fact that many people don’t get enough daily sunlight, many adults are vitamin D deficient. Health conditions and others factors like age can also affect our ability to produce enough vitamin D.
Since vegans avoid the natural food sources of vitamin D, it’s recommended that they supplement.