tired girls in school

Iron Deficiency is a Huge Problem for Girls

40 percent of girls and young women don’t get enough iron, which can impact their overall health

January 24, 2024

A recent study showed nearly 40 percent of girls and young women don’t get enough iron, most likely due to menstruation. Lack of iron, also known as iron-deficiency anemia, can affect sleep, thinking, energy and mood.

To get a better sense of this issue and what can be done about it, we asked pediatric hematology specialist Dominder Kaur, MD, what we need to know.

Why do so many young women lack iron?  

We all have ongoing needs for iron in our bodies. It’s used for making red blood cells, muscle tissue, hair, many enzymes, and other molecules inside the body. When the body loses these cells, like when our skin cells shed or we lose blood, some iron is lost as well.

The body loses iron with every menstrual cycle. At the same time, growing bodies have high iron needs. Often the amount of iron intake in adolescents is not enough to match the amount of iron they lose in their monthly cycles. So young women, especially those who do not have a high meat or green vegetable intake, end up becoming iron deficient.

For people going through pregnancy and childbirth, the body needs even more iron for the developing baby.

How much iron do you need each day?

Daily iron needs depend on a person’s age, gender, and whether they are pregnant or breastfeeding.

If you are not iron deficient, the need is between 8-18 mg of iron daily. In general, people who eat beans, dried fruits, berries, eggs, lean red meat, salmon, iron-fortified breads and cereals, peas, tofu, and dark green leafy vegetables have the iron their body needs.

What happens if you do not have enough iron in your body?

When your body does not have enough iron, it starts to conserve iron wherever it can.

For blood, the body continues making red cells until you can't produce enough hemoglobin, a substance in red blood cells that enables them to carry oxygen. If your blood cells aren’t adequate in number or unable to carry enough oxygen due to low hemoglobin, it can make you tired or short of breath. This is called iron-deficiency anemia.

What’s the difference between iron deficiency and iron-deficiency anemia?

Iron deficiency is the state of being low in body iron stores. A test called ferritin can be a good indicator of your long-term body iron stores. Generally, someone who is iron deficient has ferritin levels lower than 30 μg/L.

Iron-deficiency anemia is the condition that happens when iron deficiency progresses and is the last stage of iron deficiency. Iron deficiency without anemia is a stage that often goes undiagnosed and is a lot more prevalent than iron-deficiency anemia.

Who is at highest risk for iron-deficiency anemia?

  • People who menstruate, especially if menstrual periods are heavy
  • People who are breastfeeding, pregnant, or have recently given birth
  • People who have undergone major surgery or physical trauma
  • People with gastrointestinal diseases like Celiac disease, inflammatory bowel diseases, and peptic ulcer disease
  • People who have undergone bariatric procedures, especially gastric bypass operations
  • Vegetarians, vegans, and people whose diets do not include iron-rich foods (iron from vegetables, even those that are iron-rich, is not absorbed as well as iron from meat, poultry, and fish)
  • Children who drink more than 16 to 24 ounces a day of cow's milk (cow's milk not only contains little iron, but also can decrease absorption of iron and irritate the intestinal lining causing chronic blood loss)

How do you find out if you are iron deficient?

Simple blood tests.

Testing can be as straightforward as blood counts, showing the size and number of your red cells, or comprehensive enough to include multiple studies of body iron stores.

How do you prevent iron deficiency?

Iron comes from food. Having a diet that is balanced and rich in food sources of iron is the best way to prevent it. On average, if one eats 10 to 15 mg of iron, only 1 to 2 mg of it is absorbed into our blood via the intestines. Good sources of iron include:

  • Beef, pork, lamb, liver, and other organ meats
  • Chicken, duck, turkey, (especially dark meat), liver
  • Clams, mussels, and oysters, sardines, anchovies, and other fish
  • Leafy greens of the cabbage family: broccoli, kale, turnip greens, collard greens
  • Lima beans, pinto beans, black-eyed peas, green peas, and other legumes
  • Darker colored fruits and berries: pomegranate, blackberry, strawberry, raspberry, plums, prunes
  • Yeast-leavened whole-wheat bread and rolls
  • Some iron fortified foods to replace what you generally eat (iron fortified pastas or cereals)

What do all patients and parents ask about iron deficiency, and what do you tell them?

"How do we know the iron we eat is actually absorbed?"

Iron is best absorbed in an acidic environment in the stomach. Citrus foods aid its absorption and antacids prevent it. Also, try and consume your iron away from high calcium/dairy or wheat containing foods as the calcium in iron and phytates in wheat can interfere with iron absorption.

How long does it take to correct/treat iron deficiency?

Once iron deficiency has become evident in the form of anemia, it takes three to four months of treatment with iron supplementation.


Dominder Kaur, MD, is an Assistant Professor of Pediatrics at CUIMC