Medically reviewed by Allison Truong, M.D.

For decades, researchers have studied a link between vitamin B12 deficiency and psoriasis, leaving many people wondering whether they should take a vitamin B12 supplement (also known as cyanocobalamin) to help their condition. The short answer is: You should take the supplement only if you’re actually deficient in vitamin B12. There’s no extra benefit from taking more vitamin B12 than is necessary. Still, we decided to dig a little deeper.

Here, Elizabeth DeRobertis, a New York-based registered dietitian, answers our questions related to vitamin B12. She strongly encourages anyone to consult with their doctor before beginning any vitamin supplementation. Here’s what else she had to say.