› immune-boosting-supplements8 Best Immune-Boosting Supplements That Work, Say Doctors Jan 06, 2021 · "Vitamin C is the queen of all-natural immune boosters," says Carrie Lam, MD, co-founder of the Lam Clinic of Integrative Medicine in Tustin, CA. "It's a powerful antioxidant that's crucial for the health of capillaries, skin, teeth and bones and one of the most commonly recommended adrenal fatigue supplements."