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It’s easy to pop your multivitamin in the morning or evening and assume your body is absorbing its nutrients. But when you take your vitamins each day and what you take them with matters – quite a lot, actually. So we asked health experts Erin Macdonald and Tiffani Bachus to tell us when, exactly, is the best time to take vitamins.
What you’re taking determines the best time to take the vitamins
The timing of when you take your supplements can significantly affect the way in which your body can absorb and utilize the nutrients. Fat-soluble vitamins (A, D, E and K) and omega-3s are better absorbed when taken with a meal that contains fat. Probiotics are best taken on an empty stomach so that there’s nothing to interfere with the good bacteria from getting to work. Vitamin B12 is also better absorbed on an empty stomach because an acidic environment increases absorption.
B-complex vitamins should be taken early in the day, preferably with your first meal. They help the body produce energy from food and taking them later in the day can interfere with your sleep. Iron and calcium should never be taken together as they compete for receptor sites; take iron during the day with some vitamin C to increase absorption.
Whenever you take them, avoid taking vitamins with coffee or tea
If you drink coffee or tea, the morning might not be the best time to take your vitamins. The tannins and caffeine can interfere with the absorption of many vitamins and minerals, especially iron. Caffeine also increases urination, which can decrease the concentration of water-soluble vitamins (B-complex and C). So, wait an hour after your morning brew to take supplements. Caffeine-free herbal tea, on the other hand, contains fewer tannins than regular tea. This beverage may actually increase the absorption of certain minerals such as iron.
Editor’s Note: This advice reflects the recommendations of our dietitians, but we recommend also speaking with your health-care provider before beginning any supplement regimen. Supplement timing can vary depending on your health goals and certain health conditions.