Vitamins and Supplements You Should Never Mix

Magnesium and calcium/multivitamin

Many people like to take magnesium in the evening, as it can promote a sense of calm and supports muscle relaxation. But if you do take magnesium, Erin Stokes, ND, recommends not taking it at the same time as your multivitamin, as it may interfere with the absorption of smaller minerals found in the multivitamin, like iron and zinc. Additionally, she says to refrain from taking calcium, magnesium or zinc together as they will “compete for absorption.”