Wound Care Certified Certification (WCC) Practice Exam

Which vitamin is produced by the skin?

1. Vitamin A

2. Vitamin E

3. Vitamin C

4. Vitamin D

The correct answer is: Vitamin D

Vitamin D is unique in that it is synthesized in the skin through a chemical reaction that occurs when the skin is exposed to ultraviolet (UV) radiation from sunlight. Specifically, UVB rays stimulate the conversion of 7-dehydrocholesterol present in the skin into previtamin D3, which is then converted into vitamin D3 (cholecalciferol). This process is crucial for maintaining healthy levels of vitamin D in the body, which is essential for calcium absorption and bone health, among other functions. While vitamins A, E, and C are important for skin health and overall well-being, they are not produced by the skin. Instead, these vitamins must be obtained through diet or supplements. For example, vitamin A is obtained from foods like carrots and liver, vitamin E from nuts and green leafy vegetables, and vitamin C from citrus fruits. Thus, it is vitamin D’s unique relationship with sunlight and skin that makes it the correct answer to the question.