Iron Supplements: Dosage Advice for Who Needs Them - Dr. Axe

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Iron Supplements: Who May Need Them, Plus Dosage Recommendations


Iron supplements - Dr. Axe

Iron deficiencies are very common. In fact, many groups are at an increased risk of deficiency for this important mineral, including infants and children, women who are pregnant, those with heavy menstrual periods, and those following a vegan or vegetarian diet. For this reason, many people choose to take iron supplements.

However, a quick stroll down the supplement aisle reveals that there are a number of different options available. Not only are there several types and forms, but iron supplements are also found in a range of different dosages as well.

This comprehensive guide will cover how to take iron supplements, which forms are available and how to alleviate some of the most common side effects.


Adding iron pills to your routine has been linked to a number of potential benefits. Here are a few of the reasons you may want to consider taking an iron supplement:

  • Corrects nutritional deficiency: For those with low iron levels, taking a supplement can increase levels to prevent iron-deficiency anemia and promote the production of healthy red blood cells. This can prevent symptoms like weakness, fatigue, brittle nails and pale skin.
  • Promotes healthy pregnancy: Iron is important for fetal growth and development, which is why using an iron supplement may be advisable for pregnant women who may be following a pregnancy diet. Low iron levels during pregnancy may increase the risk of low birth weight and premature delivery.
  • Increases energy levels: Iron deficiency anemia is notorious for causing low energy levels and sluggishness. Fortunately, this can be corrected by taking an iron supplement.
  • Enhances immune function: Iron plays a key role in immune health. Providing your body with the iron that it needs can ensure that you’re able to protect against illness and infection.
  • Improves sleep quality: Some studies have found that low iron levels may be tied to decreased sleep quality. If you’re deficiency in iron, taking a supplement could potentially help boost sleep quality.

Iron Supplement Types

There are a variety of different types of iron supplements available, which can be found in liquid, capsule and tablet form. Although capsules are more widely available, some prefer taking liquid iron supplements as they may be easier to tolerate.

Here are some of the main types of iron supplements:

  • Ferric citrate: This type of iron binds to phosphates in foods and is used to lower phosphorus levels in those with chronic kidney disease.
  • Ferric sulfate: Ferric sulfate is a compound of iron and sulfate and is not often found in supplement form.
  • Ferrous sulfate: As one of the most common iron supplements on the market, ferrous sulfate is one of the first lines of defense against anemia.
  • Ferrous gluconate: This form of iron is also a common supplement made from the iron salt of gluconic acid.

Although ferrous gluconate and ferrous sulfate are two of the most widely available iron supplements, your doctor can recommend which form is best for you best on your specific health needs.


Wondering how to take iron supplements for the best absorption or what the ideal iron supplements dosage should be for you? Keep reading for the recommended dosage and the best way to take iron sulfate.

For Anemia

If you suspect that you may have anemia, it’s best to talk to your doctor to get your blood levels tested and determine the best iron supplements and treatment method for you.

Typically, taking iron supplements for anemia is recommended if you’re unable to meet your needs through food sources alone. Although the dosage can vary based on your specific needs, it’s usually advised to take around 150–200 milligrams daily, which can be split into a few smaller doses throughout the day as needed.

Ideally, supplements should be taken on an empty stomach to maximize absorption. However, some may opt to take iron pills with food, which can help reduce the risk of negative side effects.

For Women

Women require a higher amount of iron each day due to blood loss caused by menstruation. Women over age 19 need about 18 milligrams of iron daily, or around 27 milligrams daily during pregnancy. These needs decrease to around eight milligrams daily after 51.

Iron supplements for women are sometimes required, especially for those with dietary restrictions who may not regularly consume iron-rich foods like meat or fish. Iron can also be found in many multivitamins for women that help round out the diet and provide a range of vitamins and minerals. Supplements geared toward women are also available to help meet your daily needs.

For Men

Compared to women, men need a much lower amount of iron each day to help meet their daily requirements. In fact, men over age 19 need just eight milligrams of iron each day, which can be found in food sources like meat, fish, poultry and legumes.

Iron supplements for men are also available to give your intake a quick boost. Multivitamins can also be purchased, which offer iron along with an array of other key micronutrients.

For Kids

Iron is very important for infants and children as it plays a central role in promoting healthy growth and development. Iron needs vary based on age and are as follows:

  • 0-6 months: 0.27 mg
  • 7–12 months: 11 mg
  • 1–3 years: 7 mg
  • 4–8 years: 10 mg
  • 9–13 years: 8 mg
  • 14–18 years: 11 mg for males/15 mg for females

Doctors generally recommend using iron supplements for kids starting between two weeks and four months of age, depending on whether or not they were born premature and if they are consuming formula fortified with iron or other iron-rich foods.

Children should be screened for iron deficiency starting at 9–12 months of age, which can help determine whether or not supplementation is necessary. Taking a multivitamin and including a variety of iron-rich foods in the diet can help protect against deficiency.

Risks and Side Effects

Ideally, you should try to meet your iron needs primarily through food sources. Incorporating a variety of iron-rich foods into your diet not only can help you meet your daily requirements for iron, but it can also boost your intake of other important vitamins and minerals as well.

Meat, poultry, legumes, nuts and seeds are some of the top sources of iron, but it is also found in a range of fruits and vegetables, including leafy greens, tomatoes and mulberries. Consuming foods high in iron alongside foods rich in vitamin C can help effectively optimize the absorption of iron.

In some cases, however, taking a supplement may be necessary. Once you start supplementation, you may be wondering: How soon after taking iron supplements will I feel better? Unfortunately, many people also report feeling worse after taking iron supplements, as they can cause several adverse side effects when consumed on an empty stomach.

Some of the most common side effects of iron supplements include stomach pain, nausea, vomiting, constipation and diarrhea. Other less common side effects include heartburn, urine discoloration and dark stools.

Taking capsules with food is an easy way to help prevent some of the most common iron supplements side effects. However, it’s important to keep in mind that this can also reduce the absorption of iron and may decrease the effectiveness of your supplement.

Final Thoughts

  • Although it’s always better to get iron from food sources, iron supplements may be necessary in some cases.
  • Iron supplements can help correct nutritional deficiencies, promote a healthy pregnancy, increase energy levels, enhance immune function and improve sleep quality.
  • There are several types available in both capsule and liquid form, including ferric sulfate, ferrous sulfate, ferric citrate and ferrous gluconate.
  • The recommended dosage for iron can range for men, women, children and those with anemia.
  • Iron supplements can cause side effects like stomach pain, nausea, vomiting, constipation and diarrhea.
  • Taking your supplement with food can help prevent side effects but may also decrease the effectiveness of your supplement.

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