How long does it take to restore iron levels? (+1 facts)

In this article, we will discuss the timeline in which you may see improvement in your iron levels. We will also discuss certain factors which may improve or decrease iron absorption, hence delaying restoration of iron levels.

How long does it take to restore iron levels?

It often takes 3-6 months to restore your iron levels through iron supplements. However, intravenous (IV) iron may restore your iron levels within one or a few sessions. Giving iron directly into the blood through veins is the quickest way of restoring iron levels (1, 2).

You may begin to see improvement in iron levels within 2-3 weeks of taking oral iron supplements. If you are not able to tolerate oral iron supplements, you may be prescribed IV or intramuscular (IM) iron under critical supervision.

IV iron is only prescribed if you have serious iron deficiency anaemia. If you need to improve your iron levels during pregnancy, your doctor will prescribe iron supplements and diet improvement instead of IV iron.

What does research suggest?

In one of the observational studies, 100 patients with iron deficiency anaemia were given oral and IV iron to restore their iron levels. Based on the analysis, the haemoglobin increased from 6.45 to 8.84 on day 14. A further improvement was seen by day 28 where haemoglobin increased to 9.69 (1).

In the IV iron group, haemoglobin increased from 6.34 to 10.52 and 11.66 within 14 and 28 days, respectively. The ferritin levels were also better in the IV iron group (148.23) at day 14 as compared to the oral iron group (33.8).

However, a decrease in ferritin levels was observed in the IV iron group where the ferritin levels dropped to 115.76 after day 28. The same was not true for the oral group. Out of 100 patients, 18 people reported adverse effects.

The occurrence of side effects, including constipation, heartburn, nausea, and metallic taste was greater in the oral group (12/18). The IV group (6/18) reported hypotension as the major side effect (1).

How do you know your iron levels are improving?

To be sure about your iron levels, you should get a blood test. Additionally, you may know your iron levels are improving if you feel the following (2):

  • Increased energy,
  • Less body weakness,
  • Decreased dizziness, and 
  • Decreased shortness of breath.

What factors affect the restoration of iron levels?

Several factors may increase or decrease the iron absorption in the body to restore iron levels. You should always follow the guidelines provided by your doctor to ensure improvement in your iron levels.

Improved iron levels

  • Taking iron supplements and a balanced diet may improve your iron levels. However, if you are anaemic, dietary intake is not sufficient to restore iron levels.
  • Vitamin C supplements and vitamin C-rich food like oranges and orange juice are reported to improve the absorption of iron (3).
  • Lacto-fermented vegetables like sauerkraut, kimchi, and pickles are known to improve iron absorption.
  • Fruits containing citric acid (found in lemons) and malic acid (found in apples and pears) may improve iron absorption and eventually iron levels in the body.

Slow improvement in iron levels

  • Most of the iron you take from iron supplements or food is absorbed through the upper gastrointestinal tract (GIT). Malabsorption through the GIT may cause less improvement in iron levels (4).
  • Tannins present in tea, coffee, and wine may reduce the absorption of iron from the diet and iron supplements. Therefore, you should avoid such beverages while taking iron.
  • Prolonged and excessive bleeding, for example during miscarriage, may slow down the improvement of iron levels.
  • Certain medications, like proton pump inhibitors and antacids, are known to interfere with the absorption of iron in the body (5).
  • Taking expired iron supplements or those which have changed their colour may not improve the iron levels.
  • Skipping the dose and not following the prescribed dosage regimen also hinder the normalization of iron levels.
  • Taking iron supplements with certain types of food, such as milk, caffeine, and high-fibre content food, may hinder the proper absorption of iron from the pill.

How can you improve iron levels?

You can improve your iron levels by taking iron supplements, oral or IV, and improving your diet. If you are anaemic, it is important to take medication along with diet improvement for better results.


Iron supplements, oral or IV, are often prescribed to patients who are anaemic and have lower levels of iron. A common generic dose of iron (324 mg of ferrous sulphate) is often prescribed to the patient (5).

Drugs such as erythropoietic stimulating agents are prescribed to those patients who are unable to make red blood cells due to bone marrow disease, kidney disease, and iron deficiency anaemia (6).


The natural way of improving your iron levels is to consume iron-rich food. If you have anemia you will still need to take iron supplements along with a balanced diet. Iron-rich food includes red meat, egg yolk, whole grain bread, and green vegetables (such as broccoli).

The cooked liver is one of the most popular organs to improve iron levels. Some other popular iron-rich organs include the kidney, heart, and beef tongue. However, most people do not feel comfortable consuming these organs even if cooked properly.

Seafood, nuts (such as cashew nuts, peanuts, and sunflower seeds), and beans (such as red beans, soybeans, and peas) are rich in iron. You should also consume food which is rich in vitamin C and vitamin B-12 to help improve the absorption of iron in your body.

As a pharmacist, I would advise you to keep a check on your haemoglobin levels by taking regular blood tests, especially if you are pregnant or experience heavy menstrual bleeding. It may decrease the occurrence of anaemia and low iron levels. 

Improving your diet and taking iron supplements as prescribed can improve your iron levels within a few months. However, it is necessary to follow the dosage regimen recommended by your doctor to get the most benefit.

Was this helpful?

Thanks for your feedback!



Das SN, Devi A, Mohanta BB, Choudhury A, Swain A, Thatoi PK. Oral versus intravenous iron therapy in iron deficiency anemia: an observational study. Journal of Family Medicine and Primary Care. 2020 Jul;9(7):3619.


Elwood PC, Wood MM. Effect of oral iron therapy on the symptoms of anaemia. British Journal of Preventive & Social Medicine. 1966 Oct;20(4):172.


Ems T, St Lucia K, Huecker MR. Biochemistry, iron absorption.


Saboor M, Zehra A, Qamar K. Disorders associated with malabsorption of iron: A critical review. Pakistan journal of medical sciences. 2015 Nov;31(6):1549.


Alleyne M, Horne MK, Miller JL. Individualized treatment for iron-deficiency anemia in adults. The American journal of medicine. 2008 Nov 1;121(11):943-8.


Hayat A, Haria D, Salifu MO. Erythropoietin stimulating agents in the management of anemia of chronic kidney disease. Patient preference and adherence. 2008 Feb 2:195-200.