What Happens When You Take Iron and Calcium Together

Key Takeaways

When taken together, calcium can block iron absorption, making your iron supplement less effective.

Separate your doses by at least two hours to help your body absorb both nutrients properly. Take iron on an empty stomach (or with vitamin C) and calcium with meals.

Be extra cautious about this interaction if you're low in iron or at risk for an iron deficiency, such as if you're pregnant, breastfeeding, or following a vegetarian diet.

Calcium supplements can interfere with the absorption of iron, making it less effective. Taking the two supplements at different times of day can help ensure your body absorbs both nutrients as intended.

Why Calcium and Iron Don't Mix Well

Taking iron supplements with calcium can decrease iron absorption, partly due to the way calcium an