Although most people get enough iron from their diets, certain conditions, like ulcerative colitis and regular, heavy menstrual bleeding, may increase someone's iron needs and contribute to iron loss. For those people, iron supplements may help prevent iron deficiency.
If you need an iron supplement, there are different types you can take. Some of the most common include ferrous sulfate, ferrous gluconate and ferrous fumarate. If you think you need an iron supplement, always talk to your doctor before picking one up yourself to discuss the correct type and dosage for you.
What Does Iron Do?
Iron is a trace mineral that your body needs to make hemoglobin, a protein that makes up a large percentage of your red blood cells, and myoglobin, a protein in your muscles. According to the UCSF Health, about 70 percent of the iron in your body is stored in hemoglobin and myoglobin combined.
The iron in hemoglobin attaches to oxygen in your blood and brings it from your lungs to the rest of your tissues. The iron in myoglobin stores and releases oxygen to keep your muscles working properly. If you don't have enough iron in your body, your body can't properly make hemoglobin or myoglobin, and all of your tissues can become starved of oxygen.
In addition to keeping your blood healthy, contributing to the proper formation and creation of red blood cells and providing your body with oxygen, iron also supports healthy metabolism and helps your body make certain hormones and connective tissues, like collagen. It's also vital during periods of rapid growth and development, such as during puberty or when a baby is developing during pregnancy.
Recommended Daily Iron Intake
The iron RDA, or recommended dietary allowance, depends on your age and your sex. Regardless of age, adult men need 8 milligrams of iron per day. For women, the numbers are a little different. Women over the age of 50 have the same iron needs as men — 8 milligrams per day — but women of reproductive age with active menstrual cycles typically need more, or at least 18 milligrams daily, due to the regular blood loss.
If your daily iron intake is too low for an extended period of time, it can deplete your iron stores and increase your risk of developing iron deficiency and iron-deficiency anemia. If you develop a deficiency or anemia, you may experience uncomfortable symptoms like:
- Swollen tongue
- Pale skin
- Poor body temperature control
Iron Supplements for Menstruating Women
Most people in the United States get enough iron from their diets, according to the National Institutes of Health Office of Dietary Supplements. However, some groups of people are at a higher risk of iron deficiency due to increased iron needs or a loss of iron.
Women who have abnormally heavy menstrual periods, a condition known as menorrhagia, represent the highest risk group. According to the NIH Office of Dietary Supplements, heavy menstrual bleeding may actually be responsible for anywhere from 33 to 41 percent of iron-deficiency anemia in women of reproductive age and 10 percent of menstruating women are affected by it.
Who Else Needs Iron Supplements?
In addition to women who have heavy menstrual bleeding, other groups of people who are at a higher risk of iron deficiency and may benefit from iron supplements include:
- Pregnant women
- Infants and children
- People with cancer
- People with gastrointestinal disorders, like celiac disease, ulcerative colitis and Crohn's disease
- People who have undergone gastrointestinal surgery
- People with heart failure
- Frequent blood donors
Always make sure to talk to your doctor before taking any iron supplements, especially if you have an underlying medical condition.
Types of Iron Supplements
Several different forms of iron supplements are available. The two main categories of iron supplements are ferrous forms and ferric forms, which can be further broken down into ferrous sulfate, ferrous gluconate, ferrous fumarate, ferric citrate and ferric sulfate.
According to the Society for the Advancement of Blood Management, the ferrous forms of iron are generally the least expensive. The National Institutes of Health Office of Dietary Supplements also points out that your body is able to absorb the ferrous forms of iron better.
When choosing an iron supplement, it's important to look at the amount of elemental iron in each form. Elemental iron is the active part of the supplement that actually gets absorbed. While all types of iron supplements may come in the same standard tablet size, each type contains different amounts of elemental iron. Ferrous fumarate usually contains 33 percent elemental iron by weight, while ferrous sulfate contains 20 percent and ferrous gluconate falls around 12 percent, according to The National Institutes of Health Office of Dietary Supplements.
Forms of Iron Supplements
In addition to the different types of iron supplements available, there are also different forms. Over-the-counter iron supplements are available as:
- Extended-release tablets
- Chewable tablets
Liquid forms or chewable tablets are typically easier for young children and older adults to take, while adults with gastrointestinal disorders may do well with extended-release tablets. The best type and form of iron supplement for you depends on your iron level and your health status. Work with your doctor or another trusted health professional to figure out the right type of nutritional treatment plan.
Increasing Absorption of Iron Supplements
In addition to choosing the most bioavailable types of iron supplements in the right doses, you can maximize the absorption of the iron by combining your iron supplement with a vitamin C-rich source, like orange juice.
On the other hand, you should avoid certain foods and drinks while taking iron supplements. Tea, coffee and milk can reduce the absorption of iron from supplements, so these foods should be avoided for an hour before and after taking a supplement.
According to a November 2017 report in The Lancet, timing may also matter. In the study, one group of iron-deficient women received their iron supplement in two doses, while the other group was given the same amount of iron in one dose. Researchers found that those given the single doses seemed to absorb the iron better.
- Oregon State University: Linus Pauling Institute: "Iron"
- University of California San Francisco: "Hemoglobin and Functions of Iron"
- Society for the Advancement of Blood Management: "A Patient’s Guide to Oral Iron Supplements"
- The National Institutes of Health Office of Dietary Supplements: "Iron"
- The Lancet: "Iron Absorption From Oral Iron Supplements Given on Consecutive Versus Alternate Days and as Single Morning Doses Versus Twice-Daily Split Dosing in Iron-Depleted Women: Two Open-Label, Randomised Controlled Trials"
- Mayo Clinic: "Iron Supplement (Oral Route, Parenteral Route)"
- Oxford University Hospitals: "Taking Iron Supplements: Information for Patients"
- Iron Disorders Institute: "Supplements"
- MedlinePlus: "Iron Supplements"