Best time to take iron pills
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Optimal Timing for Iron Supplementation: Insights from Recent Research
Morning Dosing for Enhanced Iron Absorption
Research indicates that the best time to take iron supplements is in the morning. This timing is crucial because iron absorption is significantly higher in the morning compared to the afternoon. A study involving iron-depleted women found that fractional iron absorption (FIA) was 37% lower in the afternoon compared to the morning, likely due to higher serum hepcidin levels later in the day. Therefore, taking iron supplements in the morning can maximize their efficacy.
Impact of Dietary Factors on Iron Absorption
Dietary factors play a significant role in iron absorption. Consuming iron supplements with ascorbic acid (vitamin C) can enhance absorption. For instance, a dose of 80 mg of ascorbic acid increased iron absorption by 30%. However, higher doses of ascorbic acid (500 mg) did not further increase absorption. Conversely, consuming iron with coffee or breakfast significantly reduced iron absorption by 54% and 66%, respectively, despite the presence of ascorbic acid in the breakfast. Thus, it is advisable to take iron supplements with an ascorbic acid-rich beverage like orange juice and avoid coffee or meals during supplementation.
Alternate-Day Dosing for Improved Iron Absorption
Recent studies suggest that alternate-day dosing of iron supplements is more effective than consecutive-day dosing. In iron-depleted women, alternate-day dosing resulted in higher cumulative fractional iron absorption (21.8%) compared to consecutive-day dosing (16.3%). This is because daily dosing can increase serum hepcidin levels, which in turn reduces iron absorption from subsequent doses . Therefore, taking iron supplements on alternate days can optimize iron absorption and may be a preferable regimen.
Single Morning Doses vs. Split Doses
The method of dosing also affects iron absorption. Studies have shown that single morning doses are more effective than split doses taken twice daily. In one study, there was no significant difference in fractional or total iron absorption between once-daily and twice-daily dosing regimens, but twice-daily dosing resulted in higher serum hepcidin levels. This suggests that single morning doses are preferable to avoid the hepcidin-mediated reduction in iron absorption.
Conclusion
To maximize the efficacy of iron supplements, it is best to take them in the morning, away from meals or coffee, and with an ascorbic acid-rich beverage. Additionally, alternate-day dosing is more effective than consecutive-day dosing, and single morning doses are preferable to split doses. These strategies can help improve iron absorption and are particularly beneficial for individuals with iron deficiency or iron-deficiency anemia.
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