Get the most nutrition from your supplements

Eating a variety of foods — in as close to their natural form as possible — can give your body all the vitamins and minerals it needs. But sometimes health care providers recommend supplements.

Supplements are common for people who are pregnant or breastfeeding, have food restrictions like a vegan diet, or have certain health conditions like cancer or Crohn's disease.

If you're taking supplements, make sure you're getting the most from them. Follow these tips to help your body absorb more from your vitamin D, calcium and iron supplements.

Take vitamin D with a meal

Vitamin D is essential for muscle movement, bone health and immunity. The body can make vitamin D from sunlight, but windows, clouds and sunscreen impact the process. Food sources of vitamin D include liver, egg yolks, and fortified cereals, milks and juices.

Research suggests that the body appears to absorb about 30% more vitamin D from supplements when they're taken with a meal.

Low on calcium? Check your vitamin D

Calcium is the most abundant mineral in the body and supports bone health. Calcium is found in dairy foods like milk, cheese and yogurt. It's also in soy, sardines, tofu, and fortified cereals, juices and plant-based milks.

With all those sources of calcium, you might be wondering how you could be low. The answer might be a vitamin D deficiency.

The body needs vitamin D to absorb calcium. If your calcium levels are low, ask your health care provider whether you should take vitamin D supplements.

Take iron with vitamin C but not with calcium

Iron is a mineral that supports red blood cells, growth and development. Plant and animal foods contain iron. But the kind of iron found in plants is harder for the body to absorb.

Plant sources of iron include white beans, lentils, spinach, peas and dried fruit. Iron is also found in fortified cereals and breads.

Vitamin C can help your body absorb iron from plants and supplements. Citrus fruits, strawberries, sweet peppers, tomatoes and broccoli are sources of vitamin C.

But beware: Calcium blocks absorption of iron. Avoid taking an iron supplement with a glass of milk.

Talk to your provider

Tell your health care provider and pharmacist about all supplements and medications you take. They will check for possible interactions.

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  2. Calcium. National Institutes of Health. Accessed June 21, 2021.
  3. Vitamin D. Mayo Clinic. Accessed June 21, 2021.
  4. Dawson-Hughes B, et al. Dietary fat increases vitamin D-3 absorption. Journal Academy of Nutrition and Dietetics. 2015; doi:10.1016/j.jand.2014.09.014.
  5. Iron: Fact sheet for consumers. National Institutes of Health. Accessed June 21, 2021.