First, when we think about the best vitamins for your immune system, we typically think about pills and capsules. But nutrition doesn’t only come in pill form, Sharon Palmer, RDN, a nutritionist from Ojai, CA, tells The Healthy by Reader’s Digest. “These can be via diet—not only supplemental form,” Palmer says.

Simply put, you don’t have to get vitamins in a bottle if you have a healthfully diverse diet. Her personal faves for immune health: Vitamin C, E, D; zinc, probiotics, fiber, and mushrooms. That said, supplements in pill (or liquid) form can support your health and your immune system.

“It’s possible that taking supplements, if your diet does not contain adequate sources of nutrients that have a role in immunity, can help,” Palmer says.

Best vitamins for your immune system

1. Vitamin C

“I see people taking large doses of vitamin C—but the research is mixed on the benefits of this,” Palmer says.

A 2017 study published in Nutrients suggests that Vitamin C is essential for a strong immune system, but according to the National Center for Complementary and Integrative Health, it can’t prevent colds.

“I recommend getting enough of this high antioxidant vitamin through foods to support a healthy immune response,” Palmer adds.

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