When is the best time to take an iron supplement
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Optimal Timing for Iron Supplementation: Insights from Recent Research
Morning Iron Supplementation for Enhanced Absorption
Research indicates that the best time to take iron supplements is in the morning. This timing is recommended 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, suggesting that morning doses are more effective. Additionally, taking iron supplements with ascorbic acid (vitamin C) in the morning can further enhance absorption. For instance, 80 mg of ascorbic acid increased FIA by 30%.
Avoiding Meals and Coffee
To maximize iron absorption, it is crucial to take iron supplements away from meals and coffee. Consuming iron with coffee or breakfast can drastically reduce absorption. One study showed that coffee decreased FIA by 54%, and when combined with breakfast, the reduction was even more significant at 66%. Therefore, it is advisable to take iron supplements on an empty stomach or with a vitamin C-rich beverage like orange juice, which can increase absorption by approximately fourfold compared to taking it with breakfast.
Alternate-Day Dosing for Better Absorption
Recent studies suggest that alternate-day dosing of iron supplements may be more effective than daily dosing. This approach helps to avoid the acute increase in serum hepcidin, a hormone that inhibits iron absorption, which persists for 24 hours after an iron dose. By allowing hepcidin levels to subside, alternate-day dosing can enhance iron absorption. Research has shown that iron absorption is higher when supplements are taken on alternate days compared to consecutive days . For instance, cumulative fractional iron absorption was significantly higher in women who took iron on alternate days compared to those who took it daily.
Single Morning Doses vs. Split Doses
Providing iron supplements as a single morning dose rather than split doses throughout the day is also recommended. Split dosing can lead to higher serum hepcidin levels and reduced iron absorption from subsequent doses. Studies have found no significant difference in total iron absorption between once-daily and twice-daily dosing, but twice-daily dosing resulted in higher hepcidin concentrations . Therefore, a single morning dose is preferable to optimize iron absorption and minimize side effects.
Conclusion
In summary, the optimal regimen for taking iron supplements involves consuming them in the morning, away from meals and coffee, and with a vitamin C-rich beverage. Additionally, taking iron supplements on alternate days rather than daily, and as a single morning dose rather than split doses, can further enhance absorption and reduce side effects. These strategies are supported by multiple studies and can help individuals, especially women with iron deficiency or anemia, achieve better outcomes from their iron supplementation.
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