The Common Deficiency Most Women Never Know They Have
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For millions of women, fatigue, brain fog and feeling “off” is often dismissed as stress, depression or aging. New guidance suggests low ferritin could be the overlooked culprit
Lynn Kasiske, a website designer living in Brookfield, Wisconsin, has lived with low iron for most of her life. The 50-year-old mother of two recalls days spent battling fatigue and brain fog. Life isn’t supposed to be this hard, she’d think, observing others accomplish daily tasks with relative ease. Things aren’t supposed to be this exhausting.
Iron is essential for making oxygen-carrying red blood cells, and your body relies on the mineral to breathe, think, and move. But low iron — the most common nutritional deficiency worldwide — is woefully underrecognized and undertreated. That’s largely because the medical guidelines that drive clinical practice haven’t kept up with accumulating evidence demonstrating the adverse effects of deficiency, the benefits of screening, and the effectiveness of newer treatments.
For example, many experts now think that, for most healthy adults, ferritin (the body’s stored iron) needs to be measured at 30 ng/ml or higher to fuel essential tasks. But medical authorities, including the World Health Organization and the U.S. Centers for Disease Control (CDC), haven’t updated decades-old recommendations that set the threshold for deficiency at 15 ng/ml — half the level of iron evidence suggests is the minimum for good health.
Looking back, Kasiske says that she now realizes she was chronically deficient, with ferritin levels frequently falling below the outdated 15 ng/ml mark and occasionally tipping her into anemia. Still, doctors were quick to dismiss iron deficiency as the source of her symptoms, instead blaming an issue with her mental health. “I have been offered depression medication more times than you can shake a stick at,” says Kasiske, who has a history of anxiety, but insists that she never felt depressed. She felt doctors wanted to prescribe anti-depression drugs rather than digging deeper for other possible causes, simply “because I’m a woman and I’m tired.”
Kasiske did try an antidepressant, she says, but stopped after a few months when it did little to assuage her symptoms. While not opposed to taking medication, what she desperately wanted from her doctors was help getting to the bottom of what was making her feel bad.
“I don’t want to treat one symptom of a bigger issue,” she says. “I want to treat the issue itself.”
“It is incredibly common for iron deficiency to go undiagnosed and for women to be dismissed or diagnosed with other things,” says pediatric hematologist Angela Weyand, M.D., clinical associate professor of pediatrics, co-director of the combined hematology-gynecology program, and pediatric clinical director at the hemophilia treatment center at the University of Michigan Medical School. “I hear stories all the time of people receiving treatment for varying other diagnoses for years or not receiving treatment at all for debilitating symptoms, only to find that they were iron-deficient.”
“There are likely millions of women currently affected, but undiagnosed, who are suffering unnecessarily,” she says.
The World’s Most Common — and Overlooked — Deficiency
Unfortunately, Kasiske’s experience is all too common.
Iron deficiency affects more than 2 billion people globally and, in its most severe form, causes anemia, which is one of the leading causes of chronic illness and disability worldwide, according to a comprehensive 2025 review published in the Journal of the American Medical Association co-authored by Michael Auerbach, M.D., a hematologist and clinical professor of medicine at Georgetown University School of Medicine.
Still, until recently, says Dr. Auerbach, iron deficiency never got its due. “It was a bastard stepchild in medicine, and it didn’t deserve to be, because the morbidity is so enormous,” he says, referring to how the condition robs people of healthy, productive years of life. Sadly, iron deficiency has traditionally been overlooked and undertreated because it primarily affects women, he says. “Symptoms [of iron deficiency] are marginalized and normalized all the time.”
Sadly, iron deficiency has traditionally been overlooked and undertreated because it primarily affects women, he says. “Symptoms [of iron deficiency] are marginalized and normalized all the time.”
Experts separate iron deficiency into two categories: absolute deficiency, where the body’s ferritin storehouse is depleted, and functional deficiency, where the body can’t use the iron it has on hand. Deficiencies can be detected through a simple blood test that measures ferritin as well as transferrin saturation (TSAT), which indicates how much of the iron-transport protein transferrin is carrying iron.
Both men and women are subject to functional deficiency, as it stems primarily from chronic inflammatory conditions such as heart failure, obesity, and rheumatoid arthritis that block the release of stored iron. However, women of reproductive age are especially vulnerable to absolute deficiency due to menstrual blood loss and higher needs for the mineral during pregnancy.
As a result, more than half of adult premenopausal women are iron-deficient, according to an analysis of three years’ worth of data from the National Health and Nutritional Examination Survey (NHANES), a long-running federal program that tracks the health of nationally representative samples of Americans. The 2024 study published in the Journal of the American Medical Association found that about one-third of women aged 19 to 49 have an absolute deficiency (ferritin below 30 ng/ml) and another 19% have functional deficiency (TSAT of less than 20%). Meanwhile, only 4% of men in that age group have an absolute deficiency; 13%, a functional deficiency.
After their years of pregnancy and menstruation are behind them, the rate of absolute deficiency for women drops to 10%. However, the incidence of functional deficiency remains about the same — and is higher than in men — possibly because women are more likely to be affected by certain inflammatory conditions.
No Clear Guidelines and Not Enough Data: Why It’s Hard to Get Treatment for Low Iron
Research suggests that, like Lynn Kasiske, most people with low iron don’t get prompt, effective treatment. About six out of 10 people diagnosed with iron deficiency still have low iron levels three years after diagnosis, according to a 2024 analysis of a decade’s worth of health records of 13,084 adults treated at a large health system in Minnesota. (In this case, the researchers defined deficiency as a ferritin level at or below 25 ng/ml.)
And even when a diagnosis is made, the first and sometimes only treatment offered is often iron supplements, which commonly cause gastrointestinal symptoms such as constipation and upset stomach, and are slow to boost iron levels — if they work at all. In the Minnesota study, those who achieved healthy iron levels were far more likely than those who didn’t to have received iron through an intravenous infusion rather than just pills.
Intravenous iron typically works faster and more effectively than oral formulations, but is “drastically underused,” says Dr. Weyand. That reticence may stem from misplaced concerns about the side effects of older formulations that have since been replaced by safer alternatives, she says. “When thinking about safety, it is also important to note that oral iron is not well tolerated by a huge number of patients.”
“When thinking about safety, it is also important to note that oral iron is not well tolerated by a huge number of patients.”
One of the main contributors to the underdiagnosis and undertreatment of such a common condition is a lack of clear, consistent guidelines, says Dr. Weyand. That’s partly because deficiency affects many different organ systems, and it’s not clear which medical specialty should ultimately be responsible, she says. But the lack of solid guidance also reflects the need for better data from high-quality studies to, for example, set thresholds for healthy ferritin levels and prove the benefits of screening.
“We know prevalence is high from a young age,” notes Dr. Weyand, “but there aren’t studies actually looking at screening and outcomes.” She adds that, “there is a lot of misogyny and sexism that contribute to a lack of investment and dedication to the issue.”
How The Body Uses Iron
The body uses iron to make two key proteins: hemoglobin, the component in red blood cells that ferries oxygen from the lungs to every part of the body, and myoglobin, which provides oxygen to the muscles. In addition, the mineral is involved in a myriad of other essential processes, such as powering the chemical reactions that keep cells running, s supporting the health and functioning of vital organs, maintaining a healthy immune system, and producing messenger chemicals in your brain responsible for attention, learning, and mood.
Red blood cells contain about 60% to 70% of the body’s iron; most of the remainder is stored in the liver, spleen, and bone marrow inside a protein called ferritin. When the body’s demand for iron exceeds the supply — due to insufficient dietary intake, poor absorption, or blood loss — it draws on the ferritin storehouse.
However, if those stores are depleted, the body can’t get the iron needed to fuel its blood-cell factory. That can result in anemia — a condition characterized by a shortage of hemoglobin, red blood cells, or both — and eventually microcytosis, where, starved of vital ingredients, the bone marrow churns out red blood cells that are abnormally small. (While iron deficiency is the most common source of anemia, the condition can stem from another underlying cause — for example, in the rare, serious condition aplastic anemia, the bone marrow slows production of all types of blood cells.)
Even when the ferritin storehouse is full, people can still develop a functional deficiency if their body can’t effectively use the iron to make red blood cells. A liver hormone called hepcidin regulates the release of iron. If hepcidin levels are too high — typically due to inflammation — it locks the exit doors on iron-containing cells.
Because iron is involved in so many processes, running low can trigger a host of symptoms, including, among others, fatigue, weakness, shortness of breath, headache, dizziness, cold hands and feet, trouble concentrating, irritability, depression, restless leg syndrome, and pica (a craving for non-food substances such as ice).
Lynn Kasiske says that her doctors weren’t concerned about her iron levels until she was actually anemic. But people can start to feel bad long before then, says blood-disorder specialist Joseph Shatzel, M.D., associate professor of biomedical engineering at Oregon Health & Science University School of Medicine, pointing out that numerous studies show that a deficiency can cause symptoms before becoming severe enough to impact the bone marrow’s ability to make red blood cells.
The human body can’t produce iron, so the primary source of the mineral is food. (See “The Iron-Rich Diet” for the best sources of iron and how to maximize absorption.) However, MedShadow’s experts note that an iron-rich diet can’t compensate for factors such as poor absorption due to a gastrointestinal disorder or depleted stores from heavy periods.
“I’ve just found it very hard to move the needle in terms of iron status purely with diet,” says Dr. Shatzel.
“I’ve just found it very hard to move the needle in terms of iron status purely with diet.”
Dr. Auerbach agrees. “It’s good to have a nutritious diet,” he says, but you can’t eat your way out of a severe deficiency. “Diet won’t fix it.”
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Who’s At Risk of Running Low
While women who menstruate or are pregnant are at the highest risk, iron deficiency can affect all ages and genders. Risk factors include the following:
Blood loss. Iron loss through menstruation is one of the primary causes of iron deficiency. Research suggests that Black and Hispanic women are at higher risk of iron deficiency and anemia, likely reflecting health care disparities. For example, in the Minnesota study discussed earlier, Black patients diagnosed with iron deficiency were 27% less likely than Whites to achieve healthy iron levels within three years.
“Minoritized populations are less likely to be tested or receive treatment despite oftentimes being more likely to be affected,” says Dr. Weyand.
“Minoritized populations are less likely to be tested or receive treatment despite oftentimes being more likely to be affected,” says Dr. Weyand.
In addition, gastrointestinal blood loss can stem from conditions such as ulcers, inflammatory bowel disease, undetected bowel cancers, and long-term use of nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin, ibuprofen (Advil), or naproxen (Aleve). Undetected GI bleeding is one of the primary causes of absolute iron deficiency in men and postmenopausal women.
Endurance athletes can also run low due to factors such as increased demand, iron loss through sweat and urine, blood loss from minor bleeding in the GI tract, and a condition called foot-strike hemolysis, in which the impact of feet repeatedly hitting the ground ruptures red blood cells.
Higher demand. The recommended iron intake during pregnancy is 27 mg daily — 50% more than the 18 mg daily recommended for adult premenopausal women — and it’s hard to meet those requirements through diet alone, which is why prenatal supplements typically contain iron. Even so, more than half of pregnant women are iron-deficient, and another 7% have iron deficiency anemia, according to a recent analysis of 16 years of NHANES data conducted by Dr. Weyand and colleagues at the University of Michigan.
Adolescent girls are especially at risk not only due to menstruation, but also because they may not get enough iron in their diet to meet the demands of growth. Another analysis of NHANES data led by Dr. Weyand found that nearly 40% of females aged 12 to 21 were iron-deficient, and 6% were anemic. About 27% of girls who hadn’t had a period nonetheless had low iron, according to the study published in the Journal of the American Medical Association in 2023. (The authors defined deficiency as a ferritin level below 25 ng/ml; anemia, a hemoglobin below 12 mg/dL.)
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Due to poor diets, fast growth, and additional demands of athletics, adolescent and young adult males can also run low on iron, although that group is understudied because their risk is lower than that of girls. In a 2022 study of 493 people aged 12 to 27 seen at outpatient clinics associated with Boston Children’s Hospital, about 13% of males were iron-deficient, and none were anemic. Using more conservative definitions of deficiency as a ferritin level below 15 ng/ml and anemia as a hemoglobin below 11 mg/dL, researchers found a similar rate of anemia and a slightly lower rate of deficiency among females as in the JAMA study.
Vegans and vegetarians need more iron than meat eaters because people absorb iron better from animal products than from plants. The recommended intake for that group is about 14 mg daily for adult men and women older than 50; and about 32mg for premenopausal women. (See the tips in “The Iron-Rich Diet.”)
Conditions that reduce absorption. Several gastrointestinal conditions can decrease iron absorption, including atrophic gastritis (inflammation of the stomach lining), Celiac disease, bariatric surgery, and long-term use of stomach-acid reducers (proton pump inhibitors) such as omeprazole (Prilosec), esomeprazole (Nexium), and lansoprazole (Prevacid).
Inflammatory conditions. A chronic, low-level activation of the immune system, known as systemic inflammation, disrupts the body’s ability to absorb, transport, and use iron. Inflammatory conditions that lead to deficiencies include certain cancers; chronic kidney disease; heart failure; hypothyroidism; and autoimmune diseases such as lupus and rheumatoid arthritis.
Obesity not only causes inflammation, but is also associated with heavy periods in premenopausal women. Unfortunately, says Dr. Auerbach, physicians can have a knee-jerk response to obesity in women and blame symptoms such as fatigue on weight rather than low iron. To be sure, excess weight can contribute, he says. “But obesity plus iron deficiency? That’s a perfect storm.” And the iron deficiency part, he says, “is easy to fix really fast.”
The Case for Routine Ferritin Testing
The simplest way to detect a deficiency is to check your stored iron level with a blood test for ferritin. If you have symptoms, or a history of anemia, insurance may pay for it. But it’s a fairly inexpensive test, even if it isn’t covered. A full iron panel, including ferritin and other measures of the amount and availability of iron in your blood, costs around $60 at Quest Diagnostics, one of the nation’s largest clinical laboratories.
Due to the staggeringly high incidence of iron deficiency, all the experts MedShadow spoke with say it makes sense for a ferritin test to be part of routine screenings, at least for high-risk groups. The tests and resulting treatment are cost-effective, according to a study published in the American Journal of Hematology in April 2025. Using economic modeling, Yale University School of Medicine researchers showed that over a lifetime, annually screening women aged 18 to 51 and correcting deficiencies would improve their quality of life while adding little to overall health care costs.
The London-based International Federation of Gynecology and Obstetrics (FIGO), the world’s largest alliance of national obstetrics and gynecology societies, does recommend ferritin screening for people who menstruate or are pregnant. However, U.S. medical groups, including the American College of Obstetrics and Gynecology, which is a member of FIGO, and the U.S. Preventative Services Task Force, haven’t recommended routine ferritin testing in healthy people.
In 2022, the CDC’s own scientists published an analysis in the American Journal of Public Health concluding that the agency’s 1998 recommendations for preventing and controlling iron deficiency, based on evidence reviews from the early 1990s, are overdue for an update. However, as of this writing, the CDC website provides the same outdated advice.
As a result, iron deficiency often goes undetected until it’s advanced enough to impair the production of blood cells. Typically, low levels are flagged when a complete blood count (CBC), a blood test that measures hemoglobin and the number and size of red blood cells, detects anemia or microcytosis.
(Unfortunately, that approach overlooks women without anemia who are still low on iron. And that’s a huge swath of the population, according to a Canadian study of more than 600,000 nonpregnant women aged 15 to 54 published in the American Journal of Hematology in 2024. While 13% of those tested over the four-year study period were anemic, nearly 40% had iron deficiency without anemia.)
Iron is not just needed for making red blood cells; it’s also vital to healthy muscles, good sleep, regulating the chemicals that govern mood, and so much more, says Dr. Weyand. But in the absence of routine ferritin tests, low iron is often missed, as complaints such as fatigue or brain fog could be caused by many things, she says. “That the vast majority of people affected are women who tend to be gaslit and dismissed, makes it incredibly challenging.”
But in the absence of routine ferritin tests, low iron is often missed, as complaints such as fatigue or brain fog could be caused by many things, she says. “That the vast majority of people affected are women who tend to be gaslit and dismissed, makes it incredibly challenging.”
Women should absolutely be asking for ferritin tests, says Jamie Lo, M.D., professor of obstetrics and gynecology at the Oregon Health & Science University School of Medicine. Many people don’t realize that effective solutions such as intravenous iron are now available, she says. “It’s the lack of awareness — both from the public and health providers — about how much the benefit would be from treatment.”
But experts are working to change that.
New Guidelines Aimed at Changing Screenings
Dr. Auerbach and Dr. Weyand both helped develop draft recommendations for diagnosing iron deficiency issued by the American Society of Hematologists (ASH) last year. Those proposed guidelines call for screening high-risk groups for ferritin, and defining deficiency as 30 ng/ml or below for most adults. The group raises the ferritin cutoff to 50 ng/ml for those who have symptoms, additional risk factors for iron deficiency such as heavy periods, or who are planning to become pregnant or have surgery.
For people with chronic inflammation, ASH recommends a ferritin level of at least 100 ng/ml as well as a TSAT of 20% or higher. (Because food and drink as well as the time of day can affect iron levels in the blood, you should ideally have a TSAT test in the morning, after fasting for 12 hours.)
In February 2024, an international group of 26 experts, including those quoted in this article, convened at the Oregon Health Sciences University to develop evidence-based guidelines for treating iron deficiency. Those recommendations were published the following year in the medical journal Lancet Hematology.
The practical advice was long overdue, says Dr. Lo, co-lead author of the consensus recommendations. “Our practices were old,” she says. “There was just no unifying guideline for people to go to.”
Updated Advice on Supplements
Iron supplements remain a mainstay of treatment for most people with a deficiency who aren’t pregnant. But there is updated advice on taking them: Research shows no benefit to taking more than a single dose of 60-110 mg of iron daily. Because too much iron is toxic, the human body is designed to absorb only a small amount at a time, says Dr. Shatzel. Larger doses of oral iron not only increase the risk of side effects such as constipation and upset stomach, but also trigger the production of the hormone hepcidin, which slows absorption.
If daily dosing is hard to tolerate, research suggests that taking an iron pill every other day can be equally effective and causes fewer side effects.
The Iron-Rich Diet
People who are not affected by a condition that depletes iron stores or interferes with absorption — and that’s still the majority of Americans — can easily meet their needs for the mineral through diet.
Dietary iron comes in two forms: heme iron from animal sources such as meat, poultry, seafood, and eggs, and non-heme iron from plants such as legumes, leafy greens, nuts, seeds, and dried fruits. Iron-fortified breads, cereals, flour, pasta, and other processed foods are another source of non-heme iron. Heme iron provides the most bang for your buck. The body absorbs about 14% to 18% of iron from mixed diets that include meat and seafood, compared to 5% to 12% from vegetarian diets.
The Recommended Dietary Allowance (RDA) of iron for adult men and postmenopausal women is 8 mg of iron daily; 18 mg for women aged 19 to 50. The RDA is higher for teens aged 14 to 18 and during pregnancy and breastfeeding. Because non-heme iron is less well absorbed, recommended intakes are nearly double for people who don’t consume animal products.
For vegans and vegetarians, fortified grains can help meet daily requirements — 1 ⅓ cups of General Mill’s Multigrain Cheerios cereal, for example, contains 18 mg of iron. (See this factsheet from the U.S. Department of Agriculture for the iron content of common foods.)
Certain compounds in foods inhibit absorption, including the calcium in dairy products and supplements, as well as polyphenols found in tea, coffee, cocoa, and red wine. If you’re concerned about getting enough iron, experts recommend waiting at least an hour or two before or after an iron-rich meal to consume these.
On the other hand, you can boost the absorption of nonheme iron by eating it along with heme iron from animal products or fruits and vegetables that are high in vitamin C, such as citrus fruits and bell peppers.
Finding insufficient evidence to recommend one type of iron over another, the panel of experts behind the recommendations published in Lancet Hematology advises that it’s reasonable to start with an inexpensive over-the-counter iron salt such as ferrous sulfate, gluconate, or fumarate. The group recommends against enteric-coated or slow-release formulations because they are less well absorbed. Likewise, they warn against using topical patches and sprays, because of minimal absorption and unproven safety.
Timing is critical. A recommended approach is to take iron at bedtime when you don’t have to worry about food and drinks blocking absorption. Also, ask your doctor or pharmacist about possible interactions with anything else you take, as some drugs and supplements reduce iron absorption, or vice versa. For example, it’s advised to leave at least two hours between taking iron and any of the following:
calcium supplements
medications for reducing stomach acid
antibiotics
thyroid hormones (separate iron dosage by four to five hours)
bisphosphonate bone drugs
Parkinson’s drugs levodopa and carbidopa (separate iron dosage by as long as possible)
In addition to standalone iron pills, the mineral is found in prenatal supplements as well as formulations marketed for “fatigue,” “energy support,” and “blood-building” (Multivitamins for women older than 50 and for adult men typically contain little or no iron.). Most iron supplements contain more than the RDA, with many providing 65 mg of elemental iron, while multivitamins contain lower amounts, in line with recommended intakes. (See the “Iron-Rich Diet” for RDAs.)
It’s extremely important to resist supplementing with iron unless you’ve discussed it with your doctor. Iron overload can cause a dangerous condition called hemochromatosis, where excess iron builds up in the heart, liver, and pancreas and may eventually lead to organ failure.
And, if you have young children at home, make sure to keep any supplements containing iron locked up and out of reach. Excess iron can be deadly for little ones, and accidental ingestion of iron-containing supplements is one of the most common reasons for poison-control calls in kids younger than six.
It can take weeks or even months of oral iron to see notable changes in your iron stores. Like all the experts MedShadow spoke with for this story, Dr. Shatzel is quick to turn to intravenous iron if supplements aren’t working fast enough or cause too many side effects. “I try and recheck at six to eight weeks,” says Dr. Shatzel, who aims for ferritin levels of 50 ng/ml for most patients. “And if the ferritin is not at goal,” he says, “[I] talk to the patient about IV iron.”
Because anemia can cause severe symptoms, IV iron is typically recommended for patients whose hemoglobin levels don’t respond within two weeks.
The Life-Altering Benefits of Iron Infusions
Lynn Kasiske now knows that all those years of dutifully taking supplements that upset her stomach were largely futile. Among other risk factors for iron deficiency, she has the autoimmune disorder Celiac disease, which causes inflammation and can damage the area of the small intestine involved in iron absorption. She never got her ferritin into the healthy range until last year, when a hematologist prescribed a series of three weekly intravenous infusions of iron.
Over the next six months, her symptoms gradually resolved, she says, and she now feels dramatically better. Body and joint aches disappeared. She’s sleeping better, waking up refreshed, and no longer nauseous in the morning. “My mental clarity has definitely improved and I’m more engaged with the world around me,” she says. “I’m not sure if that is because of the lack of brain fog, or just that I have the mental and physical energy to invest in things now.”
“My mental clarity has definitely improved and I’m more engaged with the world around me,” she says. “I’m not sure if that is because of the lack of brain fog, or just that I have the mental and physical energy to invest in things now.”
Most importantly, says Kasiske, her overall health is better. “Amazingly, my Celiac reactions are not as severe, and I recover faster — which is fantastic.”
Intravenous iron bypasses your gastrointestinal system to go straight into your bloodstream, where it can be used immediately to produce red blood cells. While absorption through the gut is limited, skipping that step allows delivery of higher doses without the GI side effects of oral formulations. Intravenous formulations boost iron and hemoglobin levels more effectively than oral iron and can get people feeling better faster.
The expert recommendations published in Lancet Hematology advise IV iron for people who can’t tolerate or don’t respond enough to oral iron. It’s also the first choice for treating people with a condition that interferes with iron absorption or those who need faster relief from more severe deficiency symptoms.
During pregnancy, iron supplements are safest in the first trimester, but after that, intravenous iron is preferred because it works faster and more effectively to boost iron levels in both mother and baby.
Like other experts MedShadow spoke with, Dr. Lo typically prefers newer IV iron formulations that can be given in a single dose, rather than multiple doses over weeks. In addition to being convenient for patients, she says, single-dose IV iron works well and tends to cause fewer side effects than some older, multidose formulations.
Whether patients who achieve healthy levels will need to repeat infusions depends on the cause of the iron depletion, says Dr. Auerbach. For example, a woman who undergoes treatment to lessen heavy periods may be able to maintain iron stores by taking an iron pill every other day or not need supplemental iron at all.
Research shows that IV iron is generally safe and causes few side effects. The most serious concern is that the treatment will trigger an allergic reaction, but research suggests that this rarely happens, with an estimated occurrence of about 1 in every 200,000 infusions.
The most common adverse effect is a “Fishbane reaction,” a pseudoallergic reaction in which a patient may develop flushing and chest or back pain due to airway tightness and surrounding muscle tightness. It typically resolves by stopping the infusion and then restarting at a slower rate. In nearly 36,000 infusions administered to more than 12,000 patients, about 4% had a minor, temporary reaction according to a 2022 study published in JAMA Open Network. In that analysis of nearly seven years’ worth of data, two patients (0.01%) experienced a true allergic reaction requiring treatment with epinephrine.
Unfortunately, for patients who aren’t pregnant, insurance companies often won’t pay for IV iron until supplements have proven ineffective or intolerable, says Dr. Lo. Her preference for many patients would be to skip supplements and go straight to the intravenous solution, she says, because they can feel better in a couple of weeks.
Dr. Auerbach agrees. There’s a role for oral iron, he says. “But everything that I write, and every time I speak, I make it clear that it is my strong feeling that prudent medical treatment mandates the use of intravenous iron most of the time.”
But that way of thinking will take a huge shift in medical practice, says Dr. Lo.
It’s important to get the word out that iron deficiency without anemia can and should be treated, says Dr. Lo. And newer formulations of IV iron work quickly with very few side effects. “That’s something that also I don’t think all health care providers fully understand,” she says, “because it’s not in their repertoire of treatment options.”
While grateful to be feeling better, Kasiske wishes she had gotten the right treatment 30 or 40 years ago. “I wonder how much different my life could have been with a normal level of energy, with a normal level of ferritin,” she says. “It just feels like going through life on hard mode.”
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<p>Lynn Kasiske, a website designer living in Brookfield, Wisconsin, has lived with low iron for most of her life. The 50-year-old mother of two recalls days spent battling fatigue and brain fog. <em>Life isn’t supposed to be this hard</em>, she’d think, observing others accomplish daily tasks with relative ease. <em>Things aren’t supposed to be this exhausting</em>.<br><br>Iron is essential for making oxygen-carrying red blood cells, and your body relies on the mineral to breathe, think, and move. But low iron — the most common nutritional deficiency worldwide — is woefully underrecognized and undertreated. That’s largely because the medical guidelines that drive clinical practice haven’t kept up with accumulating evidence demonstrating the adverse effects of deficiency, the benefits of screening, and the effectiveness of newer treatments.</p>
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<p>For example, many experts now think that, for most healthy adults, ferritin (the body’s stored iron) needs to be measured at 30 ng/ml or higher to fuel essential tasks. But medical authorities, including the World Health Organization and the U.S. Centers for Disease Control (CDC), haven’t updated decades-old recommendations that set the threshold for deficiency at 15 ng/ml — half the level of iron evidence suggests is the minimum for good health.<br><br>Looking back, Kasiske says that she now realizes she was chronically deficient, with ferritin levels frequently falling below the outdated 15 ng/ml mark and occasionally tipping her into anemia. Still, doctors were quick to dismiss iron deficiency as the source of her symptoms, instead blaming an issue with her mental health. “I have been offered depression medication more times than you can shake a stick at,” says Kasiske, who has a history of anxiety, but insists that she never felt depressed. She felt doctors wanted to prescribe anti-depression drugs rather than digging deeper for other possible causes, simply “because I’m a woman and I’m tired.” </p>
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<p>Kasiske did try an antidepressant, she says, but stopped after a few months when it did little to assuage her symptoms. While not opposed to taking medication, what she desperately wanted from her doctors was help getting to the bottom of what was making her feel bad. </p>
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<p>“I don't want to treat one symptom of a bigger issue,” she says. "I want to treat the issue itself.”</p>
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<p>"It is incredibly common for iron deficiency to go undiagnosed and for women to be dismissed or diagnosed with other things,” says pediatric hematologist <a href="https://ashpublications.org/ashclinicalnews/news/9225/Hashtags-and-Hemostasis-Angela-C-Weyand-MD">Angela Weyand, M.D</a>., clinical associate professor of pediatrics, co-director of the combined hematology-gynecology program, and pediatric clinical director at the hemophilia treatment center at the University of Michigan Medical School. "I hear stories all the time of people receiving treatment for varying other diagnoses for years or not receiving treatment at all for debilitating symptoms, only to find that they were iron-deficient<em>.”</em></p>
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<p>"There are likely millions of women currently affected, but undiagnosed, who are suffering unnecessarily,” she says.</p>
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<h2 class="wp-block-heading">The World's Most Common — and Overlooked — Deficiency</h2>
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<p>Unfortunately, Kasiske’s experience is all too common.</p>
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<p>Iron deficiency affects more than 2 billion people globally and, in its most severe form, causes anemia, which is one of the leading causes of chronic illness and disability worldwide, according to a comprehensive 2025 <a href="https://jamanetwork.com/journals/jama/fullarticle/2832131">review</a> published in the<em> Journal of the American Medical Association</em> co-authored by <a href="https://ccbdmd.com/physician/michael-auerbach-md-facp/">Michael Auerbach, M.D.</a>, a hematologist and clinical professor of medicine at Georgetown University School of Medicine.<br><br>Still, until recently, says Dr. Auerbach, iron deficiency never got its due. “It was a bastard stepchild in medicine, and it didn't deserve to be, because the morbidity is so enormous,” he says, referring to how the condition robs people of healthy, productive years of life. Sadly, iron deficiency has traditionally been overlooked and undertreated because it primarily affects women, he says. “Symptoms [of iron deficiency] are marginalized and normalized all the time.”</p>
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<p>Sadly, iron deficiency has traditionally been overlooked and undertreated because it primarily affects women, he says. “Symptoms [of iron deficiency] are marginalized and normalized all the time.”</p>
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<p>Experts separate iron deficiency into two categories: <em>absolute deficiency</em>, where the body’s ferritin storehouse is depleted, and <em>functional deficiency</em>, where the body can’t use the iron it has on hand. Deficiencies can be detected through a simple blood test that measures ferritin as well as transferrin saturation (TSAT), which indicates how much of the iron-transport protein transferrin is carrying iron. </p>
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<p>Both men and women are subject to functional deficiency, as it stems primarily from chronic inflammatory conditions such as heart failure, obesity, and rheumatoid arthritis that block the release of stored iron. However, women of reproductive age are especially vulnerable to absolute deficiency due to menstrual blood loss and higher needs for the mineral during pregnancy. </p>
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<p>As a result, more than half of adult premenopausal women are iron-deficient, according to an analysis of three years' worth of data from the National Health and Nutritional Examination Survey (NHANES), a long-running federal program that tracks the health of nationally representative samples of Americans. The 2024 <a href="https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2823909">study</a> published in the <em>Journal of the American Medical Association </em>found that about one-third of women aged 19 to 49 have an absolute deficiency (ferritin below 30 <a href="http://ng.ml">ng/ml</a>) and another 19% have functional deficiency (TSAT of less than 20%). Meanwhile, only 4% of men in that age group have an absolute deficiency; 13%, a functional deficiency.</p>
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<p>After their years of pregnancy and menstruation are behind them, the rate of absolute deficiency for women drops to 10%. However, the incidence of functional deficiency remains about the same — and is higher than in men — possibly because women are more likely to be affected by certain inflammatory conditions.</p>
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<h2 class="wp-block-heading">No Clear Guidelines and Not Enough Data: Why It’s Hard to Get Treatment for Low Iron</h2>
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<p>Research suggests that, like Lynn Kasiske, most people with low iron don’t get prompt, effective treatment. About six out of 10 people diagnosed with iron deficiency still have low iron levels three years after diagnosis, according to a 2024 <a href="https://ashpublications.org/bloodadvances/article/8/23/6029/517369/Iron-deficiency-resolution-and-time-to-resolution">analysis</a> of a decade’s worth of health records of 13,084 adults treated at a large health system in Minnesota. (In this case, the researchers defined deficiency as a ferritin level at or below 25 ng/ml.) </p>
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<p>And even when a diagnosis is made, the first and sometimes only treatment offered is often iron supplements, which commonly cause gastrointestinal symptoms such as constipation and upset stomach, and are slow to boost iron levels — if they work at all. In the Minnesota study, those who achieved healthy iron levels were far more likely than those who didn’t to have received iron through an intravenous infusion rather than just pills. </p>
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<p>Intravenous iron typically works faster and more effectively than oral formulations, but is “drastically underused,” says Dr. Weyand. That reticence may stem from misplaced concerns about the side effects of older formulations that have since been replaced by safer alternatives, she says. "When thinking about safety, it is also important to note that oral iron is not well tolerated by a huge number of patients.”</p>
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<p>"When thinking about safety, it is also important to note that oral iron is not well tolerated by a huge number of patients.”</p>
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<p>One of the main contributors to the underdiagnosis and undertreatment of such a common condition is a lack of clear, consistent guidelines, says Dr. Weyand. That’s partly because deficiency affects many different organ systems, and it’s not clear which medical specialty should ultimately be responsible, she says. But the lack of solid guidance also reflects the need for better data from high-quality studies to, for example, set thresholds for healthy ferritin levels and prove the benefits of screening.</p>
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<p>"We know prevalence is high from a young age,” notes Dr. Weyand, "but there aren't studies actually looking at screening and outcomes." She adds that, “there is a lot of misogyny and sexism that contribute to a lack of investment and dedication to the issue.”</p>
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<h2 class="wp-block-heading">How The Body Uses Iron </h2>
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<p>The body uses iron to make two key proteins: <strong>hemoglobin</strong>, the component in red blood cells that ferries oxygen from the lungs to every part of the body, and <strong>myoglobin</strong>, which provides oxygen to the muscles. In addition, the mineral is involved in a myriad of other essential processes, such as powering the chemical reactions that keep cells running, s supporting the health and functioning of vital organs, maintaining a healthy immune system, and producing messenger chemicals in your brain responsible for attention, learning, and mood.</p>
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<p>Red blood cells contain about 60% to 70% of the body’s iron; most of the remainder is stored in the liver, spleen, and bone marrow inside a protein called ferritin. When the body's demand for iron exceeds the supply — due to insufficient dietary intake, poor absorption, or blood loss — it draws on the ferritin storehouse.</p>
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<p>However, if those stores are depleted, the body can’t get the iron needed to fuel its blood-cell factory. That can result in anemia — a condition characterized by a shortage of hemoglobin, red blood cells, or both — and eventually microcytosis, where, starved of vital ingredients, the bone marrow churns out red blood cells that are abnormally small. (While iron deficiency is the most common source of anemia, the condition can stem from another underlying cause — for example, in the rare, serious condition aplastic anemia, the bone marrow slows production of all types of blood cells.)</p>
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<p>Even when the ferritin storehouse is full, people can still develop a functional deficiency if their body can’t effectively use the iron to make red blood cells. A liver hormone called hepcidin regulates the release of iron. If hepcidin levels are too high — typically due to inflammation — it locks the exit doors on iron-containing cells.</p>
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<p>Because iron is involved in so many processes, running low can trigger a host of symptoms, including, among others, fatigue, weakness, shortness of breath, headache, dizziness, cold hands and feet, trouble concentrating, irritability, depression, restless leg syndrome, and pica (a craving for non-food substances such as ice).</p>
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<p>Lynn Kasiske says that her doctors weren’t concerned about her iron levels until she was actually anemic. But people can start to feel bad long before then, says blood-disorder specialist <a href="https://www.ohsu.edu/providers/joseph-shatzel-md-mcr">Joseph Shatzel, M.D.</a>, associate professor of biomedical engineering at Oregon Health & Science University School of Medicine, pointing out that numerous studies show that a deficiency can cause symptoms before becoming severe enough to impact the bone marrow’s ability to make red blood cells. </p>
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<p>The human body can’t produce iron, so the primary source of the mineral is food. (See "The Iron-Rich Diet” for the best sources of iron and how to maximize absorption.) However, MedShadow’s experts note that an iron-rich diet can’t compensate for factors such as poor absorption due to a gastrointestinal disorder or depleted stores from heavy periods.</p>
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<p>“I've just found it very hard to move the needle in terms of iron status purely with diet,” says Dr. Shatzel.</p>
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<p>“I've just found it very hard to move the needle in terms of iron status purely with diet.”</p>
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<p>Dr. Auerbach agrees. “It’s good to have a nutritious diet," he says, but you can’t eat your way out of a severe deficiency. “Diet won’t fix it.”</p>
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<h2 class="wp-block-heading">Who’s At Risk of Running Low</h2>
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<p>While women who menstruate or are pregnant are at the highest risk, iron deficiency can affect all ages and genders. Risk factors include the following:</p>
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<p>Blood loss. Iron loss through menstruation is one of the primary causes of iron deficiency. Research suggests that Black and Hispanic women are at higher risk of <a href="https://www.sciencedirect.com/science/article/pii/S2475299123112431">iron deficiency </a>and <a href="https://www.cdc.gov/nchs/products/databriefs/db519.htm#section_2">anemia, </a>likely reflecting health care disparities. For example, in the Minnesota <a href="https://ashpublications.org/bloodadvances/article/8/23/6029/517369/Iron-deficiency-resolution-and-time-to-resolution">study</a> discussed earlier, Black patients diagnosed with iron deficiency were 27% less likely than Whites to achieve healthy iron levels within three years. </p>
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<p>“Minoritized populations are less likely to be tested or receive treatment despite oftentimes being more likely to be affected,” says Dr. Weyand.</p>
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<p>“Minoritized populations are less likely to be tested or receive treatment despite oftentimes being more likely to be affected,” says Dr. Weyand.</p>
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<p>In addition, gastrointestinal blood loss can stem from conditions such as ulcers, inflammatory bowel disease, undetected bowel cancers, and long-term use of nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin, ibuprofen (Advil), or naproxen (Aleve). Undetected GI bleeding is one of the primary causes of absolute iron deficiency in men and postmenopausal women.<br><br>Endurance athletes can also run low due to factors such as increased demand, iron loss through sweat and urine, blood loss from minor bleeding in the GI tract, and a condition called foot-strike hemolysis, in which the impact of feet repeatedly hitting the ground ruptures red blood cells.</p>
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<p><strong><em>Higher demand.</em></strong> The recommended iron intake during pregnancy is 27 mg daily — 50% more than the 18 mg daily recommended for adult premenopausal women — and it’s hard to meet those requirements through diet alone, which is why prenatal supplements typically contain iron. Even so, more than half of pregnant women are iron-deficient, and another 7% have iron deficiency anemia, according to a recent <a href="https://onlinelibrary.wiley.com/doi/pdf/10.1002/ajh.70207">analysis</a> of 16 years of NHANES data conducted by Dr. Weyand and colleagues at the University of Michigan.</p>
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<p>Adolescent girls are especially at risk not only due to menstruation, but also because they may not get enough iron in their diet to meet the demands of growth. Another analysis of NHANES data led by Dr. Weyand found that nearly 40% of females aged 12 to 21 were iron-deficient, and 6% were anemic. About 27% of girls who hadn’t had a period nonetheless had low iron, according to the <a href="https://jamanetwork.com/journals/jama/fullarticle/2806540">study</a> published in the <em>Journal of the American Medical Association</em> in 2023. (The authors defined deficiency as a ferritin level below 25 ng/ml; anemia, a hemoglobin below 12 mg/dL.)</p>
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<figure class="wp-block-image size-large"><img src="https://medshadow.org/wp-content/uploads/2026/07/shutterstock_560320918-1024x683.jpg" alt="" class="wp-image-31036"/><figcaption class="wp-element-caption">Photo: Shutterstock</figcaption></figure>
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<p>Due to poor diets, fast growth, and additional demands of athletics, adolescent and young adult males can also run low on iron, although that group is understudied because their risk is lower than that of girls. In a 2022 <a href="https://pubmed.ncbi.nlm.nih.gov/34796723/">study</a> of 493 people aged 12 to 27 seen at outpatient clinics associated with Boston Children’s Hospital, about 13% of males were iron-deficient, and none were anemic. Using more conservative definitions of deficiency as a ferritin level below 15 ng/ml and anemia as a hemoglobin below 11 mg/dL, researchers found a similar rate of anemia and a slightly lower rate of deficiency among females as in the JAMA study.</p>
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<p>Vegans and vegetarians need more iron than meat eaters because people absorb iron better from animal products than from plants. The recommended intake for that group is about 14 mg daily for adult men and women older than 50; and about 32mg for premenopausal women. (See the tips in “The Iron-Rich Diet.”)</p>
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<p><strong><em>Conditions that reduce absorption. </em></strong>Several gastrointestinal conditions can decrease iron absorption, including atrophic gastritis (inflammation of the stomach lining), Celiac disease, bariatric surgery, and long-term use of stomach-acid reducers (<a href="https://medshadow.org/conditions-treatments/alzheimers-dementia/the-ppi-debate-are-heartburn-drugs-like-prilosec-and-nexium-linked-to-dementia/">proton pump inhibitors</a>) such as omeprazole (Prilosec), esomeprazole (Nexium), and lansoprazole (Prevacid).</p>
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<p><strong><em>Inflammatory conditions.</em></strong> A chronic, low-level activation of the immune system, known as systemic inflammation, disrupts the body’s ability to absorb, transport, and use iron. Inflammatory conditions that lead to deficiencies include certain cancers; chronic kidney disease; heart failure; hypothyroidism; and autoimmune diseases such as lupus and rheumatoid arthritis. </p>
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<p>Obesity not only causes inflammation, but is also associated with heavy periods in premenopausal women. Unfortunately, says Dr. Auerbach, physicians can have a knee-jerk response to obesity in women and blame symptoms such as fatigue on weight rather than low iron. To be sure, excess weight can contribute, he says. “But obesity plus iron deficiency? That’s a perfect storm.” And the iron deficiency part, he says, “is easy to fix really fast.”</p>
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<h2 class="wp-block-heading">The Case for Routine Ferritin Testing</h2>
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<p>The simplest way to detect a deficiency is to check your stored iron level with a blood test for ferritin. If you have symptoms, or a history of anemia, insurance may pay for it. But it’s a fairly inexpensive test, even if it isn’t covered. A full iron panel, including ferritin and other measures of the amount and availability of iron in your blood, costs around $60 at Quest Diagnostics, one of the nation’s largest clinical laboratories.</p>
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<p>Due to the staggeringly high incidence of iron deficiency, all the experts MedShadow spoke with say it makes sense for a ferritin test to be part of routine screenings, at least for high-risk groups. The tests and resulting treatment are cost-effective, according to a <a href="https://onlinelibrary.wiley.com/doi/10.1002/ajh.27686?__cf_chl_tk=hrKca8KhSZ3mFs4iK_KXc2UedBEFnlJ7QNnIsGvuUfQ-1776375921-1.0.1.1-CAc1sUW79fqdiJCpDb_ptMWCtStBG3DlSs_hZ0w5OE4">study</a> published in the <em>American Journal of Hematology</em> in April 2025. Using economic modeling, Yale University School of Medicine researchers showed that over a lifetime, annually screening women aged 18 to 51 and correcting deficiencies would improve their quality of life while adding little to overall health care costs. </p>
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<p>The London-based International Federation of Gynecology and Obstetrics (FIGO), the world’s largest alliance of national obstetrics and gynecology societies, does recommend ferritin screening for people who menstruate or are pregnant. However, U.S. medical groups, including the American College of Obstetrics and Gynecology, which is a member of FIGO, and the U.S. Preventative Services Task Force, haven’t recommended routine ferritin testing in healthy people.</p>
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<p>In 2022, the CDC’s own scientists published an analysis in the American Journal of Public Health concluding that the agency’s 1998 recommendations for preventing and controlling iron deficiency, based on evidence reviews from the early 1990s, are overdue for an update. However, as of this writing, the CDC website provides the same outdated advice.</p>
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<p>As a result, iron deficiency often goes undetected until it’s advanced enough to impair the production of blood cells. Typically, low levels are flagged when a complete blood count (CBC), a blood test that measures hemoglobin and the number and size of red blood cells, detects anemia or microcytosis.</p>
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<p>(Unfortunately, that approach overlooks women without anemia who are still low on iron. And that’s a huge swath of the population, according to a Canadian <a href="https://onlinelibrary.wiley.com/doi/10.1002/ajh.27352">study</a> of more than 600,000 nonpregnant women aged 15 to 54 published in the<em> American Journal of Hematology</em> in 2024. While 13% of those tested over the four-year study period were anemic, nearly 40% had iron deficiency without anemia.)</p>
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<p>Iron is not just needed for making red blood cells; it’s also vital to healthy muscles, good sleep, regulating the chemicals that govern mood, and so much more, says Dr. Weyand. But in the absence of routine ferritin tests, low iron is often missed, as complaints such as fatigue or brain fog could be caused by many things, she says. "That the vast majority of people affected are women who tend to be gaslit and dismissed, makes it incredibly challenging.”</p>
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<p>But in the absence of routine ferritin tests, low iron is often missed, as complaints such as fatigue or brain fog could be caused by many things, she says. "That the vast majority of people affected are women who tend to be gaslit and dismissed, makes it incredibly challenging.”</p>
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<p>Women should absolutely be asking for ferritin tests, says <a href="https://www.ohsu.edu/providers/jamie-lo-md-mcr">Jamie Lo, M.D.</a>, professor of obstetrics and gynecology at the Oregon Health & Science University School of Medicine. Many people don’t realize that effective solutions such as intravenous iron are now available, she says. “It’s the lack of awareness — both from the public and health providers — about how much the benefit would be from treatment.”</p>
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<p>But experts are working to change that. </p>
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<h3 class="wp-block-heading">New Guidelines Aimed at Changing Screenings</h3>
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<p>Dr. Auerbach and Dr. Weyand both helped develop draft recommendations for diagnosing iron deficiency issued by the American Society of Hematologists (ASH) last year. Those proposed guidelines call for screening high-risk groups for ferritin, and defining deficiency as 30 ng/ml or below for most adults. The group raises the ferritin cutoff to 50 ng/ml for those who have symptoms, additional risk factors for iron deficiency such as heavy periods, or who are planning to become pregnant or have surgery.</p>
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<p>For people with chronic inflammation, ASH recommends a ferritin level of at least 100 ng/ml as well as a TSAT of 20% or higher. (Because food and drink as well as the time of day can affect iron levels in the blood, you should ideally have a TSAT test in the morning, after fasting for 12 hours.) </p>
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<p>In February 2024, an international group of 26 experts, including those quoted in this article, convened at the Oregon Health Sciences University to develop evidence-based guidelines for treating iron deficiency. Those <a href="https://pubmed.ncbi.nlm.nih.gov/40306833/">recommendations</a> were published the following year in the medical journal <em>Lancet Hematology</em>. </p>
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<p>The practical advice was long overdue, says Dr. Lo, co-lead author of the consensus recommendations. “Our practices were old,” she says. “There was just no unifying guideline for people to go to.”</p>
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<h2 class="wp-block-heading">Updated Advice on Supplements </h2>
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<p>Iron supplements remain a mainstay of treatment for most people with a deficiency who aren’t pregnant. But there is updated advice on taking them: Research shows no benefit to taking more than a single dose of 60-110 mg of iron daily. Because too much iron is toxic, the human body is designed to absorb only a small amount at a time, says Dr. Shatzel. Larger doses of oral iron not only increase the risk of side effects such as constipation and upset stomach, but also trigger the production of the hormone hepcidin, which slows absorption.</p>
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<p>If daily dosing is hard to tolerate, research suggests that taking an iron pill every other day can be equally effective and causes fewer side effects.</p>
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<div class="wp-block-myplugin-custom-alignment-block alignright"><h2>The Iron-Rich Diet</h2><p>People who are not affected by a condition that depletes iron stores or interferes with absorption — and that’s still the majority of Americans — can easily meet their needs for the mineral through diet.<br><br>Dietary iron comes in two forms: heme iron from animal sources such as meat, poultry, seafood, and eggs, and non-heme iron from plants such as legumes, leafy greens, nuts, seeds, and dried fruits. Iron-fortified breads, cereals, flour, pasta, and other processed foods are another source of non-heme iron. Heme iron provides the most bang for your buck. The body absorbs about 14% to 18% of iron from mixed diets that include meat and seafood, compared to 5% to 12% from vegetarian diets. <br><br>The <a href="https://ods.od.nih.gov/factsheets/Iron-HealthProfessional/#h3">Recommended </a>Dietary Allowance (RDA) of iron for adult men and postmenopausal women is 8 mg of iron daily; 18 mg for women aged 19 to 50. The RDA is higher for teens aged 14 to 18 and during pregnancy and breastfeeding. Because non-heme iron is less well absorbed, recommended intakes are nearly double for people who don’t consume animal products. <br><br>For vegans and vegetarians, fortified grains can help meet daily requirements — 1 ⅓ cups of General Mill’s Multigrain Cheerios cereal, for example, contains 18 mg of iron. (See this <a href="https://www.dietaryguidelines.gov/sites/default/files/2024-08/Food-Sources-Iron-Standard_508C.pdf">factsheet</a> from the U.S. Department of Agriculture for the iron content of common foods.)<br><br>Certain compounds in foods inhibit absorption, including the calcium in dairy products and supplements, as well as polyphenols found in tea, coffee, cocoa, and red wine. If you’re concerned about getting enough iron, experts recommend waiting at least an hour or two before or after an iron-rich meal to consume these. <br><br>On the other hand, you can boost the absorption of nonheme iron by eating it along with heme iron from animal products or fruits and vegetables that are high in vitamin C, such as citrus fruits and bell peppers.<br></p></div>
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<p>Finding insufficient evidence to recommend one type of iron over another, the panel of experts behind the recommendations published in <em>Lancet Hematology</em> advises that it’s reasonable to start with an inexpensive over-the-counter iron salt such as ferrous sulfate, gluconate, or fumarate. The group recommends against enteric-coated or slow-release formulations because they are less well absorbed. Likewise, they warn against using topical patches and sprays, because of minimal absorption and unproven safety. </p>
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<p>Timing is critical. A recommended approach is to take iron at bedtime when you don’t have to worry about food and drinks blocking absorption. Also, ask your doctor or pharmacist about possible interactions with anything else you take, as some drugs and supplements reduce iron absorption, or vice versa. For example, it’s advised to leave at least two hours between taking iron and any of the following:</p>
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<li>calcium supplements</li>
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<li>medications for reducing stomach acid</li>
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<li>antibiotics</li>
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<li>thyroid hormones (separate iron dosage by four to five hours)</li>
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<li>bisphosphonate bone drugs</li>
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<li>Parkinson’s drugs levodopa and carbidopa (separate iron dosage by as long as possible) </li>
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<p>In addition to standalone iron pills, the mineral is found in prenatal supplements as well as formulations marketed for “fatigue,” “energy support,” and “blood-building” (Multivitamins for women older than 50 and for adult men typically contain little or no iron.). Most iron supplements contain more than the RDA, with many providing 65 mg of elemental iron, while multivitamins contain lower amounts, in line with recommended intakes. (See the “Iron-Rich Diet” for RDAs.) </p>
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<p>It’s extremely important to resist supplementing with iron unless you’ve discussed it with your doctor. Iron overload can cause a dangerous condition called hemochromatosis, where excess iron builds up in the heart, liver, and pancreas and may eventually lead to organ failure.</p>
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<p>And, if you have young children at home, make sure to keep any supplements containing iron locked up and out of reach. Excess iron can be deadly for little ones, and accidental ingestion of iron-containing supplements is one of the most common reasons for poison-control calls in kids younger than six.</p>
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<p>It can take weeks or even months of oral iron to see notable changes in your iron stores. Like all the experts MedShadow spoke with for this story, Dr. Shatzel is quick to turn to intravenous iron if supplements aren’t working fast enough or cause too many side effects. “I try and recheck at six to eight weeks,” says Dr. Shatzel, who aims for ferritin levels of 50 ng/ml for most patients. “And if the ferritin is not at goal,” he says, “[I] talk to the patient about IV iron." </p>
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<p>Because anemia can cause severe symptoms, IV iron is typically recommended for patients whose hemoglobin levels don’t respond within two weeks.</p>
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<h2 class="wp-block-heading">The Life-Altering Benefits of Iron Infusions</h2>
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<p>Lynn Kasiske now knows that all those years of dutifully taking supplements that upset her stomach were largely futile. Among other risk factors for iron deficiency, she has the autoimmune disorder Celiac disease, which causes inflammation and can damage the area of the small intestine involved in iron absorption. She never got her ferritin into the healthy range until last year, when a hematologist prescribed a series of three weekly intravenous infusions of iron. </p>
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<p>Over the next six months, her symptoms gradually resolved, she says, and she now feels dramatically better. Body and joint aches disappeared. She’s sleeping better, waking up refreshed, and no longer nauseous in the morning. “My mental clarity has definitely improved and I’m more engaged with the world around me,” she says. “I’m not sure if that is because of the lack of brain fog, or just that I have the mental and physical energy to invest in things now.” </p>
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<p>“My mental clarity has definitely improved and I’m more engaged with the world around me,” she says. “I’m not sure if that is because of the lack of brain fog, or just that I have the mental and physical energy to invest in things now.” </p>
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<p>Most importantly, says Kasiske, her overall health is better. “Amazingly, my Celiac reactions are not as severe, and I recover faster — which is fantastic.” </p>
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<p>Intravenous iron bypasses your gastrointestinal system to go straight into your bloodstream, where it can be used immediately to produce red blood cells. While absorption through the gut is limited, skipping that step allows delivery of higher doses without the GI side effects of oral formulations. Intravenous formulations boost iron and hemoglobin levels more effectively than oral iron and can get people feeling better faster.</p>
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<p>The expert recommendations published in <em>Lancet Hematology</em> advise IV iron for people who can’t tolerate or don’t respond enough to oral iron. It’s also the first choice for treating people with a condition that interferes with iron absorption or those who need faster relief from more severe deficiency symptoms.</p>
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<p>During pregnancy, iron supplements are safest in the first trimester, but after that, intravenous iron is preferred because it works faster and more effectively to boost iron levels in both mother and baby. </p>
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<p>Like other experts MedShadow spoke with, Dr. Lo typically prefers newer IV iron formulations that can be given in a single dose, rather than multiple doses over weeks. In addition to being convenient for patients, she says, single-dose IV iron works well and tends to cause fewer side effects than some older, multidose formulations. </p>
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<p>Whether patients who achieve healthy levels will need to repeat infusions depends on the cause of the iron depletion, says Dr. Auerbach. For example, a woman who undergoes treatment to lessen heavy periods may be able to maintain iron stores by taking an iron pill every other day or not need supplemental iron at all.</p>
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<p>Research shows that IV iron is generally safe and causes few side effects. The most serious concern is that the treatment will trigger an allergic reaction, but research suggests that this rarely happens, with an estimated occurrence of about 1 in every 200,000 infusions.<br><br>The most common adverse effect is a "Fishbane reaction,” a pseudoallergic reaction in which a patient may develop flushing and chest or back pain due to airway tightness and surrounding muscle tightness. It typically resolves by stopping the infusion and then restarting at a slower rate. In nearly 36,000 infusions administered to more than 12,000 patients, about 4% had a minor, temporary reaction according to a 2022 <a href="https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2790508">study</a> published in <em>JAMA Open Network. </em>In that analysis of nearly seven years’ worth of data, two patients (0.01%) experienced a true allergic reaction requiring treatment with epinephrine.</p>
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<p>Unfortunately, for patients who aren’t pregnant, <a href="https://medshadow.org/drug-updates-recalls/drug-safety/what-is-step-therapy-and-why-it-might-delay-your-medication/">insurance companies often won’t pay</a> for IV iron until supplements have proven ineffective or intolerable, says Dr. Lo. Her preference for many patients would be to skip supplements and go straight to the intravenous solution, she says, because they can feel better in a couple of weeks. </p>
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<p>Dr. Auerbach agrees. There’s a role for oral iron, he says. “But everything that I write, and every time I speak, I make it clear that it is my strong feeling that prudent medical treatment mandates the use of intravenous iron most of the time.”</p>
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<p>But that way of thinking will take a huge shift in medical practice, says Dr. Lo. </p>
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<p>It’s important to get the word out that iron deficiency without anemia can and should be treated, says Dr. Lo. And newer formulations of IV iron work quickly with very few side effects. “That's something that also I don't think all health care providers fully understand,” she says, "because it's not in their repertoire of treatment options.”</p>
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<p>While grateful to be feeling better, Kasiske wishes she had gotten the right treatment 30 or 40 years ago. “I wonder how much different my life could have been with a normal level of energy, with a normal level of ferritin,” she says. "It just feels like going through life on hard mode.”</p>
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