A ’startling’ number of young women and girls are deficient in iron. Experts say their symptoms are often brushed off. Here's why.

Iron deficiency and iron-deficiency anemia are fairly common medical issues that can leave people feeling tired and even short of breath. But new research has found there’s one group that may be at particular risk of developing iron deficiency — young women and girls on their periods.

The study, which was published in JAMA, analyzed data on iron blood levels from more than 3,400 women and girls between the ages of 12 and 21 who participated in the National Health and Nutrition Examination Survey. The researchers discovered that, between 2003 and 2020, almost 40% of women and girls were deficient in iron and 6% actually had iron-deficiency anemia — a condition where the blood doesn't have enough healthy red blood cells, which carry oxygen to the body's tissues.

Having a period was a risk factor for both conditions, although more than 25% of those who hadn't yet gotten their period also had iron deficiency. As a result, the researchers concluded that "current screening guidance may miss many individuals with iron deficiency."

"I see a lot of iron deficiency and iron deficiency anemia in menstruating adolescents but hypothesized that, as a specialist, I was only seeing the tip of the iceberg and that this issue was incredibly prevalent in the general population," lead study author Dr. Amanda Weyand, a pediatric hematologist at the University of Michigan Medical School, tells Yahoo Life. “We know that menstruation, especially heavy menstrual bleeding, which is also quite prevalent in the general population, is a risk factor for iron deficiency. But menstruation is stigmatized within our society, so issues may not be raised by patients or may be dismissed by providers.”

But why might having a period lead to iron deficiency — even anemia — and how concerning is this? Experts break it down.

Why might young women and girls struggle with iron deficiency?

It's easy to assume that the blood loss from menstruation will cause temporary iron deficiency during a woman’s period, but experts say it doesn’t work that way. “Iron deficiency is not something that happens for a week or a month and then resolves,” Deborah Cohen, associate professor in the Department of Clinical and Preventive Nutrition Science at Rutgers University, tells Yahoo Life.

Weyand agrees. “It’s less likely that people are low for just a week or so a month,” she says. “Menstruation does lead to iron deficiency, but this is more of a chronic issue with longer-term iron stores.”

Being low in iron “means that you probably don’t have enough to meet your needs, including having enough to fill your iron storage proteins. Otherwise you would be able to use iron stores when you needed them, like during your period,” Sonya Angelone, a registered dietitian and spokeswoman for the Academy of Nutrition and Dietetics, tells Yahoo Life.

The study didn’t look at why this population may have low iron levels — it merely discovered that this is happening. However, there are some theories.

One is that bleeding on a monthly basis can raise the risk of iron deficiency and even anemia. “During menstruation, a woman loses iron in menstrual blood. That can deplete iron stores,” registered dietitian Jessica Cording, author of The Little Book of Game Changers, tells Yahoo Life. Women and girls who have more heavy periods may be at greater risk of this, she says.

Weyand says she thinks iron deficiency may be“secondary to menstruation” and is an intergenerational issue. “Iron deficiency has been normalized systemically by our reference ranges and dismissal of women’s symptoms,” she says. “Menstruation is stigmatized and we know that although heavy menstrual bleeding is prevalent — affecting anywhere from one in four to one in two over the lifetime — many women do not seek care for this issue and may not even recognize it as abnormal.”

People as a whole are also having less iron in their diet, which may factor in, Weyand says, although she says that “this plays a lesser role.”

Regardless of the reason behind it, “the numbers are pretty startling,” women’s health expert Dr. Jennifer Wider, tells Yahoo Life. “It’s an issue that doctors need to discuss with their patients and suggest ways to manage and prevent effectively,” she adds.

What is the danger in having low iron levels?

There is a range with iron deficiency and, with that, symptoms can vary. “Some people don’t feel their best when their iron is even on the low side,” Angelone says. “Some people can end up feeling absolutely exhausted,” Cording says.

Iron deficiency and iron-deficiency anemia can also cause no symptoms or vague symptoms, such as fatigue, headache and trouble concentrating, “which may be commonly brushed off,” Cohen says. That can lead to people being undiagnosed, she says.

But while iron deficiency can lead to uncomfortable symptoms such as headache and fatigue, Cohen notes that most people who experience it have no signs at all. “‘Harm’ from iron deficiency is not common and really depends on the cause of the iron deficiency,” she says.

If left untreated over a long period of time, however, iron deficiency anemia may lead to heart problems such a a rapid or irregular heartbeat, low birth weight babies during pregnancy and growth problems in children and infants, according to the Mayo Clinic.

How to treat low iron levels

Weyand says women and girls who have periods should be aware of how common iron deficiency is among them. Cording recommends that people be mindful of their iron intake, focusing on consuming iron-rich foods such as fortified breakfast cereals, white beans, lentils, spinach and tofu.

If you suspect that you or a loved one has low iron levels, Cohen says it’s important to get checked by a doctor to be sure (it’s a simple blood test). Your doctor may recommend that you take an iron supplement if your iron deficiency is severe, but Cohen says you shouldn’t go straight to supplementing without seeing a medical provider first. “Self-prescribing iron supplements is not recommended as they have side effects — significant constipation which can be severe especially if a high dose is taken or if taken by a youngster — and, if the iron deficiency anemia is due to a medical condition, the signs and symptoms may go away but the underlying medical condition may not,” she says.

If you have signs of iron deficiency or you’re concerned about your iron intake, talk to your doctor. They can offer personalized next steps.

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