Iron deficiency is more common than any other micronutrient deficiency, according to the American Society of Hematology. Months or years may pass before it is diagnosed, despite the accompanying fatigue, weakness, mental confusion, and other symptoms.
A study conducted in 2024 indicated that about one-third of adults in the United States may suffer from iron deficiency. Research has also shown that regular examinations of children and pregnant women, who are among the groups most vulnerable to this deficiency, may fail to detect more than 70% of cases.
In this context, some people diagnose themselves with iron deficiency, based on dark circles under the eyes and pale skin. Social media influencers call these features the “ferritin face,” after the protein responsible for storing the element in the body.
The difference between iron deficiency and anemia
Anemia occurs when the body does not have enough red blood cells to transport oxygen to various organs and tissues.
Its symptoms may include fatigue, dizziness, shortness of breath, heart palpitations, cold hands and feet, pale skin, brittle nails, and hair loss.
Anemia often results from a deficiency of iron, which is an essential element to support brain and muscle health, and the body also needs it to produce hemoglobin, which is responsible for transporting oxygen in the blood.
In general, iron is stored in a protein called ferritin, which the body uses to produce hemoglobin in new red blood cells.
Low levels are an indication of a decline in iron stores, which may affect the production of red blood cells and lead to anemia.
But iron deficiency may cause the same symptoms even when hemoglobin levels and red blood cell counts are within normal ranges.
It may also lead to restless legs syndrome, or a desire to eat non-food items, such as snow and mud.
The reason for craving these substances is still unclear, but it is believed that the body is trying to compensate for the lack of iron from the surrounding environment.
What do the new guidelines say about iron tests?
The level of iron in the blood is generally affected by the type of food and the timing of eating it.
Therefore, ferritin analysis is one of the most important tests used to evaluate the body's nutrient stores, according to Dr. Jacqueline Powers, chief of hematology at Texas Children's Hospital and lead author of the 2026 guidelines.
The World Health Organization recommends diagnosing iron deficiency in school-age children and adults when the ferritin level falls below 15 nanograms per milliliter.
On the other hand, researchers believe that this number may not include many cases of people suffering from iron deficiency at levels close to the threshold.
New guidelines from the American Society of Hematology set ferritin levels, which require a diagnosis of iron deficiency, at 20 nanograms per milliliter in children, 30 in most adults, and 50 in those with menorrhagia or other risk factors, while the threshold rises to 100 in adults with inflammatory conditions.
“These guidelines emphasize the importance of screening for iron deficiency, whether the patient has anemia or not, as early diagnosis helps reduce future complications and deal with less obvious symptoms,” Powers said.
Who should be tested for iron deficiency?
Symptoms of iron deficiency may range from fatigue and exhaustion, mental confusion and difficulty concentrating, to the desire to chew substances such as ice, according to Dr. Ariela Marshall, an associate professor of medicine at the University of Minnesota.
She added that these symptoms may appear together or separately, or they may not appear at all.
Despite social media posts linking pale skin, hair loss, dry skin, and “ferritin face” as signs of iron deficiency, both Powers and Marshall are skeptical that low levels can be diagnosed by taking a selfie.
In general, women are more susceptible to iron deficiency than men due to blood loss during menstruation, and the risk increases in those who suffer from menorrhagia.
The risk of deficiency also increases in children and pregnant women due to the increased body needs for iron during growth and pregnancy.
Chronic digestive diseases, such as irritable bowel syndrome and celiac disease, may affect the body's ability to absorb iron from food.
Iron deficiency may also result in gastrointestinal bleeding, which is sometimes an early sign of colon cancer.
As for endurance athletes, they need more iron than most people. Its deficiency may lead to a decline in their ability to perform exercises at the usual level.
Powers believes that ferritin testing is a suitable option for those who suffer from constant fatigue, despite following a balanced diet, sleeping well, and adhering to healthy habits.
Oral iron supplements may help relieve symptoms within weeks or months, but it is necessary to consult a doctor to determine the underlying cause of iron deficiency.
