Should You Take Iron at Night or Morning for Optimal Absorption?

January 11, 2026 •

3 min read

According to a 2018 study in the journal Blood, iron absorption was up to 40% higher when supplements were taken in the morning compared to the evening. This key finding, among others, helps answer the question: should you take iron at night or morning for optimal results?

Quick Summary

The ideal time to take iron is the morning on an empty stomach due to lower hepcidin levels and higher stomach acid, both of which enhance absorption. Evening intake is an alternative if morning dosing causes side effects like nausea or heartburn. Consistency is the most important factor for success.

Key Points

Morning is Generally Best: Taking iron in the morning on an empty stomach maximizes absorption due to naturally low hepcidin levels and higher stomach acid.
Pair with Vitamin C: Enhancing iron absorption is possible by taking your supplement with a source of vitamin C, like orange juice.
Avoid Inhibitors: For at least an hour after taking iron, avoid foods and drinks that inhibit absorption, such as coffee, tea, and dairy products.
Nighttime is a Valid Alternative: If morning dosing causes severe side effects like nausea, a nighttime dose with a small snack can improve tolerance.
Consistency Trumps Timing: The most important factor is taking your supplement consistently. A regular routine at a less optimal time is better than an inconsistent optimal one.
Personalize Your Strategy: Consider factors like stomach sensitivity, interactions with other medications, and lifestyle when determining the best time for you.
Consult a Professional: Always talk to a doctor or pharmacist to discuss your specific needs and find a suitable iron formulation and timing.

Morning: The Optimal Choice for Maximum Iron Absorption

Taking iron in the morning is generally recommended for maximizing absorption. This is because several physiological factors are most favorable for iron uptake at this time, particularly when taken about an hour before breakfast on an empty stomach.

Scientific Rationale for Morning Dosing

Morning intake leverages two key biological rhythms:

Hepcidin levels: Hepcidin, a hormone controlling iron absorption, is naturally lowest in the morning. Lower hepcidin allows for better iron uptake, a phenomenon supported by research showing increased absorption during morning hours.
Stomach acid: Iron absorbs better in an acidic environment. Gastric acid is typically higher in the morning after fasting, which helps convert iron into a more easily absorbed form.

Enhancing Morning Iron Absorption

Maximize your morning dose by:

Pairing with vitamin C: Vitamin C significantly boosts iron absorption by converting it to the ferrous form. Consider taking your supplement with orange juice or a vitamin C tablet.
Avoiding inhibitors: Certain substances hinder absorption. For one to two hours after your iron dose, avoid dairy, coffee, tea, and high-fiber foods.

Night: A Viable Alternative for Managing Side Effects

While morning is ideal for absorption, taking iron at night can be beneficial if morning doses cause significant side effects such as nausea or an upset stomach.

Addressing Common Side Effects

Taking iron in the evening can help some individuals sleep through potential discomfort.

With a small snack: To ease stomach sensitivity, taking the supplement with a small, bland snack can be helpful. This is preferable to skipping doses altogether.
Upright position: To reduce the risk of heartburn, remain upright for at least an hour after taking a nighttime dose.

Other Considerations for Nighttime Dosing

Some individuals with iron-deficient restless legs syndrome report improved symptoms with nighttime iron. Be mindful of other supplements; for example, calcium should be taken several hours apart from iron.

Comparison Table: Morning vs. Night Iron Intake


Feature	Morning Intake	Nighttime Intake
Optimal Absorption	Highest due to low hepcidin and high stomach acid.	Lower as hepcidin levels are typically higher.
Side Effect Management	Potential for increased nausea on an empty stomach.	Can help mitigate nausea by sleeping through it.
Convenience & Routine	Easy to integrate before breakfast.	May suit those with irregular morning schedules.
Interactions	Easier to separate from common morning inhibitors.	Requires planning to avoid evening meals, calcium, and medications.
Energy Effects	May boost energy throughout the day.	Energy benefits are not immediate.

Beyond Timing: Consistency is Key

Consistency is the most critical factor for improving iron status. Taking iron regularly, even at a less optimal time, is more effective than inconsistent dosing. If morning side effects cause you to miss doses, switching to evenings or alternate-day dosing might be more beneficial.

The Role of Lifestyle and Formulation

Individual needs vary. Pregnant individuals with morning sickness might find evening doses easier to tolerate. The type of iron also matters; ferrous bisglycinate is often gentler than ferrous sulfate. Always consult a healthcare professional to determine the best approach for you.

Conclusion: Personalizing Your Approach

While morning is generally favored for optimal iron absorption, the best time to take iron depends on individual tolerance and the ability to maintain a consistent schedule. Balancing optimal absorption with minimizing side effects is key. For many, a morning dose with vitamin C is ideal, avoiding inhibiting foods afterward. For others, a consistent evening dose with a small snack may be the most sustainable option. Discussing your needs with a healthcare provider is essential to find a schedule and formulation that supports your health goals. The National Institutes of Health Office of Dietary Supplements website provides additional information.

Frequently Asked Questions

Yes, some studies suggest that alternate-day iron dosing can be more effective and cause fewer gastrointestinal side effects than daily dosing, as it prevents the iron-regulating hormone hepcidin from inhibiting absorption.

Ideally, you should wait at least one hour after taking an iron supplement before eating, especially if taking it on an empty stomach. If you take it with food to avoid stomach upset, wait at least two hours before or after to maximize absorption.

You should avoid taking iron with dairy products (milk, yogurt), coffee, tea, eggs, and high-fiber foods. The calcium in dairy and compounds like tannins in coffee and tea can significantly reduce iron absorption.

Yes, iron supplements can cause gastrointestinal side effects such as nausea, upset stomach, and constipation. If this occurs, try taking the supplement with a small amount of food or switching to a gentler formulation, such as ferrous bisglycinate.

No, calcium interferes with iron absorption. If you take both supplements, you should separate them by several hours. For instance, take iron in the morning and calcium in the evening.

For most people, there is no significant difference in absorption between tablets and liquid iron. However, liquid forms can be faster-acting and might be better for those with absorption issues or difficulty swallowing pills.

If you forget a dose, take it as soon as you remember, unless it is almost time for your next dose. Do not double up on your dose. Consistency over time is more important than a single missed dose.