How redefining 'normal' iron levels could help women's health
CBC
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Nicole Williams often felt tired when she was in high school and university, relying on coffee to chase away fatigue. Then the persistent exhaustion was followed by anxiety that left her unable to concentrate.
"I was getting dysfunctional," Williams, now 43, recalled. "It made it hard to drive, made it hard to get through the day at work and have a kid."
Around 2015, Williams was going from doctor to doctor, trying to figure out the source of her tiredness. Blood test results seemed normal, including those that measure low iron, a common cause of fatigue in women.
Doctors attributed the Toronto woman's symptoms to mental health issues. It took years until a specialist uncovered the real cause: iron deficiency.
Dr. Michelle Sholzberg, a hematologist and scientist at St. Michael's Hospital in Toronto, told Williams her exhaustion and anxiety could "100 per cent" be explained by low iron. But Williams's levels weren't low enough to match what Ontario defined as "low," at that time.
The problem, Sholzberg contends, is that medicine has long been wrong about what a "healthy" level of iron is.
Earlier this month, Ontario updated its limit on ferritin — the protein that stores iron — to 30 micrograms per litre. Previously, the threshold between low and normal varied by lab, from 10 to 15 micrograms per litre.
Sholzberg wants to raise the bar across Canada on what a "normal" level of iron is to 30 micrograms per litre, which she said is based on the best available scientific evidence to avoid symptoms. Doing so could catch and treat the deficiency earlier.
Physicians call iron deficiency a largely hidden problem that often goes undiagnosed. The Canadian Health Measures Survey conservatively estimates it hits seven per cent of women of childbearing age.
"Every single day of my career, I have met patient after patient with unaddressed iron deficiency," Sholzberg said.
Yet once iron deficiency is treated, with oral supplements or, in some cases, IV infusion, patients report feeling better.
"I've had many patients tell me that their life has changed, that they feel like Superwoman, that they can concentrate again, that they can go through a day without feeling exhausted."
Red blood cells require iron to ferry oxygen to the brain and heart. The nutrient also fuels the chemical reactions keeping us alive.