Can i take calcium and iron together
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Can I Take Calcium and Iron Together?
Introduction to Calcium and Iron Supplementation
Calcium and iron are essential minerals that play crucial roles in the human body. Calcium is vital for bone health, while iron is necessary for the production of hemoglobin and overall oxygen transport in the blood. However, the interaction between these two minerals, especially when taken together, has been a topic of extensive research.
Effects of Combined Calcium and Iron Supplementation
Impact on Iron Absorption
Several studies have investigated the impact of calcium on iron absorption. It has been consistently found that calcium can inhibit the absorption of iron when both are ingested simultaneously. This inhibition is more pronounced with nonheme iron (the type of iron found in plant-based foods) compared to heme iron (found in animal products) . For instance, calcium supplements like calcium citrate and calcium phosphate significantly reduced iron absorption by 49% and 62%, respectively, when taken with food.
Long-Term Effects on Iron Status
Despite the short-term inhibitory effects on iron absorption, long-term studies suggest that high calcium intake does not necessarily compromise overall iron status. A study on adolescent girls showed that long-term calcium supplementation did not affect biomarkers of iron status, such as hemoglobin and serum ferritin levels, even when calcium was taken with the main meal. Similarly, another study concluded that combined calcium and iron supplementation was as effective as iron supplementation alone in reducing iron deficiency anemia in Bolivian schoolchildren.
Dietary Considerations and Recommendations
Timing and Meal Composition
The timing of calcium and iron intake can influence their absorption. Taking calcium supplements with meals that are high in iron can inhibit iron absorption more significantly than when taken separately. However, separating the intake of these supplements may not always be practical or necessary. A systematic review concluded that prescribing the separation of prenatal calcium and iron supplements is unlikely to affect the anemia burden significantly .
Role of Ascorbic Acid
Ascorbic acid (vitamin C) can enhance iron absorption and counteract the inhibitory effects of calcium. Adding ascorbic acid to iron-fortified foods has been shown to significantly increase iron absorption, even in the presence of calcium. This suggests that including vitamin C-rich foods in meals can help mitigate the negative impact of calcium on iron absorption.
Conclusion
In summary, while calcium can inhibit iron absorption when taken together, the long-term impact on iron status appears to be minimal. For individuals concerned about iron deficiency, it may be beneficial to consider the timing of supplementation and include vitamin C-rich foods to enhance iron absorption. However, the necessity of separating calcium and iron intake remains debatable, and more research is needed to provide definitive guidelines.
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