Nearly 1 in 3 Americans may have one of two forms of iron deficiency, even if they don’t have a health condition for which they would be screened for

Could You Be Iron Deficient and Not Know It? New Research Says Yes—Here's How to Find Out

Nearly 1 in 3 Americans may have one of two forms of iron deficiency, even if they don’t have a health condition for which they would be screened for

• A new study found that nearly 1 in 3 Americans may have one of two forms of iron deficiency.
• More than half of the participants with an iron deficiency did not have a medical reason to be regularly screened and likely would not have been screened outside of the study.
• While most people can meet their iron needs through a balanced diet, routine screenings can help to identify an iron deficiency.
  

Nearly one in three adults in the United States may have an iron deficiency, according to a recent study.

For the research, published in JAMA Network Open, scientists from Boston's Brigham and Women’s Hospital analyzed the iron levels of a nationally representative sample of about 8,000 adults. The pool included people who wouldn’t usually be screened for an iron deficiency, like those without heart failure, chronic kidney disease, or anemia—when the body doesn’t have enough red blood cells to carry oxygen to tissues. 

Researchers found that an estimated 14% of adults in the study met the criteria for absolute iron deficiency, which means there isn’t enough iron in the body. Not having enough iron can cause symptoms such as fatigue, shortness of breath, difficulty concentrating, and palpitations. 

The team also discovered that about 15% of adults fulfilled the criteria for functional iron deficiency, which occurs when the iron in the body is stored away but not readily available for use.

“I would really emphasize the importance of distinguishing between absolute and functional iron deficiency,” senior author Leo Buckley, a clinical pharmacy specialist in the Department of Pharmacy at Brigham and Women’s Hospital, told Health. “Half of all iron deficiency cases were functional, but we don’t yet know the consequences of untreated functional iron deficiency in the general population.”

Buckley said that regardless, the findings should pave the way for further research into who should and shouldn’t be screened for an iron deficiency. “We need studies to understand the implications of broader iron deficiency screening recommendations,” he said.

Examining Iron Levels

Previous research examining the prevalence of iron deficiency in the U.S. has focused on high risk groups such as infants, pregnant women, and people of childbearing age, the study noted.

But Buckley said that he and his colleagues had looked at European data suggesting that 15% to 25% of blood donors, who wouldn't necessarily be at high risk for iron deficiency, were indeed iron deficient. “That statistic strongly suggested to us that we would find a similar prevalence of iron deficiency in the U.S.,” he said. 

To test their theory, the scientists gathered data from 8,021 people from the U.S. aged 18 or older who were representative of the general population. The information came from the National Health and Nutritional Examination Survey and included levels of participants’ iron between 2017 and 2020.

In addition to finding that about a third of participants had some form of iron deficiency, they also found that only about 33% of adults with absolute iron deficiency and 14% of adults with functional iron deficiency had a potential medical reason to be screened for the condition. That means most of the participants likely would not have had a routine screening for iron deficiency. 

Furthermore, a minority of people with iron deficiency reported taking iron supplements—22% to 35% of women and 12% to 18% of men. 

“We don’t have apples-to-apples comparisons between our study and prior studies because of differences in how iron deficiency was measured,” Buckley said. “But it seems that absolute iron deficiency has increased slightly in prevalence.”

While Buckley said the team’s data was limited in that it couldn’t assess trends over a long period, the sample did include a diverse group of Americans.

“So, the big picture findings of our study certainly can be applied to the U.S. overall,” he said.

What Causes Iron Deficiency?

People are at higher risk of iron deficiency when they have any blood loss, an increased need for iron, or a decreased ability to absorb iron. 

In general, women who menstruate are at a higher risk than the general population. Pregnant women are also especially at risk for low iron because they need 27 milligrams of dietary iron daily, rather than the 18 milligrams recommended for most other women.

A 2022 study estimated that more than 70% of iron deficiency may go undiagnosed among pregnant women and children, who are also at higher risk.

“Breastfeeding people should be screened regarding their diet and vitamin supplements to confirm they are meeting recommended daily allowances of iron and other nutrients,” Mary Jacobson, MD, a board-certified OB/GYN, told Health.

Other risk factors for iron deficiency include taking certain medications, gastrointestinal conditions, prior abdominal surgery, inflammatory conditions, and restrictive diets.

What to Do If You Think You Have an Iron Deficiency

Many people are only tested for iron deficiency once their blood work shows lower than normal hemoglobin counts. 

However, if someone is experiencing new fatigue or other symptoms of iron deficiency, they should ask their primary care provider to be tested specifically for an iron deficiency.

Katie E. Golden, MD, a board-certified emergency medicine physician specializing in cardiovascular health, told Health that people might want to request a transferrin saturation test, which measures the percentage of transferrin saturated with iron. Transferrin is the main protein in the blood that binds to iron, and low levels may indicate an iron deficiency. 

“If someone is iron deficient, they should be treated with iron supplements,” Golden said. “Their primary care provider can help them figure out the right kind and dose based on their individual circumstances. If someone is not iron deficient, they do not need supplements. But it never hurts to make sure they are getting enough iron from their diet.”

Several types of animal protein, such as red meat and fish, are high in iron. Plant-based foods like legumes, soy, leafy greens, and different kinds of nuts are also iron-rich.

While most people can meet their iron needs through a balanced diet, the study's findings show that many people are likely going undiagnosed.

“The downstream, unintended consequences of routine screening need to be defined before making strong recommendations,” he said. “For people who feel like they have symptoms of iron deficiency, I would start with a conversation with your provider because the symptoms can be non-specific, and you want to make sure that you’re covering all your bases.”

This story originally appeared on: Health News - Author:Lauryn Higgins