What Do New Iron Deficiency Guidelines Mean For You?

In my early twenties, a routine hemoglobin test at a blood drive revealed that my iron levels were too low to donate blood. The nurse urged me to see my doctor, who diagnosed me with iron deficiency anemia—the start  of years spent taking daily iron supplements and getting frequent blood tests. 

Since then, my levels of ferritin (the blood protein that contains iron; ferritin levels are a key measure of the body’s iron reserves), have fluctuated between zero and a modest 34 micrograms per litre, often dipping during times of higher iron demands, such as pregnancy. There is no consensus on a normal range of ferritin, but the World Health Organization advises that healthy adult females should have ferritin levels that fall between 15 and 150 micrograms per litre.

Despite the fluctuations in my ferritin levels, one thing has remained consistent: my symptoms. I can sense when my iron stores drop too low because I become exhausted doing simple activities and my heart beats rapidly or erratically. Even at ferritin levels that fell within the normal range of the WHO guidelines, I still experienced intermittent fatigue, headaches and hair loss. 

My doctor maintained there was nothing else I could do—until in September 2024, when the Ontario Association of Medical Laboratories advised physicians in a memo that as best practice, 30 micrograms per litre should be considered the new baseline for ferritin. 

What is iron deficiency and anemia?

“Iron is a critical component of a lot of different cells and chemical reactions in our body,” says Dr. Michelle Sholzberg, a hematologist and scientist at St. Michael's Hospital in Toronto—including the growth of muscle, cognitive function and energy. It’s also the most common nutritional deficiency in the world.

Iron deficiency occurs when levels of ferritin drop below a threshold that is determined by the individual laboratory or hospital conducting the blood test (and that threshold varies across different labs and hospitals). Iron deficiency will inevitably lead to anemia if iron stores are not replaced, which means the body is unable to produce hemoglobin, an iron-rich protein in red blood cells responsible for carrying oxygen to organs and tissues. Anemia is diagnosed through a complete blood count test, including hemoglobin levels.  

While not all people who have iron deficiency will develop anemia, it’s more likely to happen if the body’s iron demands increase, such as during pregnancy, or excessive blood loss or malabsorption of iron (for example during celiac disease) make it harder for the body to maintain its stores.

Sholzberg notes that iron deficiency is an issue of health equity because it largely affects females, children and individuals who are marginalized or minoritized.

What are the symptoms of iron deficiency?

There is a long list of symptoms associated with iron deficiency, and people can be affected in different ways. Fatigue and a lack of energy are common symptoms. Other symptoms include pale skin, brittle nails and hair loss. Pica, a disorder in which people eat things not usually considered food, is a less common symptom.

Anemia can cause all of the above symptoms, in addition to irritability or anxiety, increased heart rate and shortness of breath or chest pain when exercising. Fainting can also occur.

How is iron deficiency diagnosed?

Because physicians review thousands of patient test results, Sholzberg says that universal upper and lower limits for ferritin make it easier for physicians to see when results are abnormal. The lower limit for females has ranged anywhere from an average of 8 to 20 micrograms per litre of ferritin. Ontario is the first province to provide new guidelines for testing for iron deficiency, although many of Canada’s private and community laboratories have now adopted Ontario's new lower limit.

Sholzberg and other experts had previously voiced concern that standard ferritin thresholds were inappropriately low, and left vulnerable individuals undiagnosed and untreated. “We hope that other provinces and territories will adopt a similar evidence-based intervention and implementation strategy,” says Sholzberg. “Just because [low iron levels among women] is common doesn’t mean it’s normal,”

Dr. Menaka Pai, a hematologist and professor of medicine at McMaster University in Hamilton, Ont., says that the normalization of health issues women face isn’t intentional, but an example of sexism in medicine.

“The place where people start feeling good and where our body is able to do its job with enough iron is actually 30 micrograms per litre of ferritin,” says Pai.

Sholzberg and Pai have been involved in efforts to establish better guidance on the identification of iron deficiency, using the best available scientific literature and consensus between practicing hematologists. 

What are the treatment options?

Most people with iron deficiency or anemia are advised to eat a diet rich in iron—including foods such as red meat, green leafy vegetables and beans—and take an over-the-counter oral iron supplement. However, some people can’t tolerate oral iron because of digestive side effects, such as constipation or diarrhea, or because of conditions that affect absorption. Another treatment option is intravenous iron supplementation, which Pai says is very effective for people who can’t tolerate oral iron. Unfortunately, IV iron is not universally covered by health-care plans and often needs to be paid for out-of-pocket—an obvious barrier for many people. 

Who is primarily affected by iron deficiency?

"In people of reproductive age, the number-one cause [for] is heavy menstrual bleeding,” says Sholzberg.

If physicians don't manage the heavy bleeding, the deficiency will continue. “Discussing vaginal blood loss is incredibly stigmatized and not really properly addressed by many healthcare providers,” she says.

Inadequate nutrition can also lead to iron deficiency. “This issue illustrates broader themes in medicine and how we take care of vulnerable people in our communities,” says Pai. “We know that people who have food insecurity are at risk.”

Rates of iron deficiency vary across countries and populations, but one Canadian study found that nearly 40 percent of non-pregnant females were iron deficient, and the risk increased for those living in low income households. 

In a study of over 60,000 women in Canada and the U.S., researchers found that compared to white and Asian patients, the prevalence of iron deficiency was significantly greater in Hispanic and Black women. Pai says that issues of racism and equity in medicine create the “perfect storm” for iron deficiency.

What do the new guidelines mean for patients?

Sholzberg hopes that the new definition will lead to a cascade of positive change, not just within Canada, but elsewhere in the world. “By taking this step forward, it gives other people permission to create a precedent,” she says.

Both Sholzberg and Pai want to see clinical guidelines be developed, which help practitioners know when to screen people for iron deficiency and how to treat them. “Guideline creation is really important because it gives Canadians and the people who look after them a roadmap to care,” says Pai.

Awareness is also essential, especially for patients who need better information about iron deficiency and heavy menstrual bleeding. Pai emphasizes the importance of helping people—particularly those at risk—recognize that their symptoms may not be normal and feel empowered to discuss them with a healthcare provider.

That’s exactly what I did. Tackling the source of my anemia—heavy menstrual bleeding—has been a game-changer. I recently underwent an endometrial ablation, a procedure that has significantly reduced my bleeding, and at last check, my ferritin level was above the new lower limit. More importantly, I feel better, which is the real measure of success. Improved health and well-being is not just about the numbers.