Vitamin D is a fat-soluble nutrient. It is one of the 24 micronutrients critical for human survival. The sun is the major natural source, through eliciting vitamin D production in the skin, but vitamin D is also found naturally in oily fish and eggs and is often added to milk and milk alternatives.
What is vitamin D?
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•Last Updated: May 16, 2025
Vitamin D is a fat-soluble nutrient essential for human survival and is one of 24 critical micronutrients. It is primarily produced in the skin through sunlight exposure and can also be found in oily fish, eggs, and fortified milk products.