By Vance Voetberg
Iron deficiency affects about 30 percent of the global population, making it the most common nutritional deficiency in the world. It is also one of the most harmful.
Consequences vary from impaired brain development in children and increased dementia risks in adults to hindered cognitive functioning and a crippled immune system across all age groups.
While children and pregnant women regularly get tested for anemia—a condition of not having enough red blood cells—doctors don’t typically screen adults for iron deficiency. Also, the condition can initially be so mild that it goes unnoticed for months or even years.
Many people know iron deficiency leads to anemia.
Iron is needed to make hemoglobin, a protein that gives red blood cells their color and transports oxygen throughout the body.
But its function is more than that.
1. Neurogenerative Diseases
Energy production requires iron.
Inside almost every cell, “powerhouse” mitochondria generate energy for all bodily functions, from squatting 300 pounds to forming thoughts. This cellular energy is called adenosine triphosphate, or ATP.
Iron is a raw material of ATP; lack of it impairs ATP production, which can manifest in the form of neurodegenerative diseases.
Low iron levels can lead to reduced energy production in neurons. This energy deficit can contribute to the dysfunction and eventual death of dopamine-producing neurons, potentially exacerbating the progression of Parkinson’s disease.
One study found that low iron levels were associated with disease severity in Parkinson’s patients, while another showed an association between early-life anemia and the later development of Parkinson’s disease.
“Iron is essential for proper brain development and function,” Dr. Matt Angove, a licensed naturopathic physician, told The Epoch Times.
Anemia is a risk factor for dementia, according to a 2020 study of over 26,000 participants. The research suggests that iron supplementation reduces dementia risk in iron-deficient anemia patients. A 2023 study reaffirmed iron deficiency is associated with greater all-cause dementia risk in women.
“These findings are unsurprising, knowing that iron plays critical roles in neurotransmitter synthesis and maintenance of myelin,” Dr. Angove said.
Myelin sheaths, which are layers of protein and fat, protect brain and spinal cord nerves. Demyelination mainly causes multiple sclerosis. A Journal of Clinical Investigation study found iron can repair demyelinating lesions.
2. Chronic Fatigue
A 2020 study in the European Journal of Clinical Nutrition found associations between fatigue and iron deficiency in 224 hospitalized patients between the ages of 65 and 95. The study also reported that 11 percent of community dwellers and over 50 percent of nursing home residents and inpatients are iron deficient.
Because oxygen relies on iron for transport, iron-deficiency anemia causes fatigue and poor muscle function. Even iron deficiency without anemia can cause extreme fatigue, highlighting iron’s vital roles.
3. Compromised Immune System
As iron is critical for the circulatory and nervous systems, research shows it also maintains a robust immune system.
People with COVID-19 were found to have less iron in their blood and more substances like ferritin, a protein that stores iron, compared to healthy individuals or the normal range. Even two months after getting COVID-19, these patients still showed low iron and high ferritin levels.
“Ferritin is an acute phase reactant. High ferritin is a sign of inflammation,” said Dr. Angove. During an infection, the body “pulls iron out of circulation and hides it in ferritin so viruses can’t utilize it.”
Who’s Most at Risk of Iron Deficiency?
Though anyone may develop iron deficiency without sufficient dietary iron, three groups are disproportionately affected: children, women, and older adults.
In children, rapid growth causes deficiency, which impairs cognitive, motor, socioemotional, and neurophysiological development short- and long-term, according to research. It also has the potential to cause permanent damage to brain development.
Menstruating women are also at high risk since they lose iron monthly due to bleeding. A study of 236 menstruating women found 27 percent were anemic and 60 percent were severely iron deficient.
Iron deficiency is common in active women, Dr. Angove said. He described a 17-year-old volleyball player whose arm went numb mid-game. Physicians suspected autoimmunity, but her ferritin was just 2 ng/mL, far below the optimum of 40 to 300 ng/mL.
“We started her on iron, and a week later, she was playing in the state volleyball tournament,” Dr. Angove added. Her complete blood count was normal, so doctors didn’t suspect deficiency issues. “She could have easily been down the road of specialist after specialist and ended up getting told she has a mental illness if we didn’t check her ferritin and get her iron levels up,” he said. “A patient’s need is often so simplistic that it confounds brilliant physicians.”
Pregnant women are also at a much higher risk. Iron deficiency is common due to increased blood volume, fetal development needs, placenta formation, and maternal tissue growth.
How to Spot Silent Iron Deficiency
From irritability to headaches, signs of the condition can be wide-ranging, Dr. Angove said.
Hence, they are often overlooked.
The most common sign is fatigue, but others may include:
- Pale skin: Skin appears unusually pale or washed out.
- Weakness: The person may exhibit decreased strength and physical stamina.
- Shortness of breath: The person may have difficulty breathing, especially during physical activity.
- Headache: Persistent or frequent headaches are common.
- Dizziness: The person may feel lightheaded or dizzy.
- Cold hands and feet: The person’s hands and feet may feel unusually cold.
- Brittle nails: Nails become fragile and prone to breaking.
- Pica (craving nonfood items): The person may have unusual cravings for substances like ice or dirt.
- Restless legs syndrome: Uncomfortable leg sensations while resting or sleeping are common.
- Irritability: The person may easily become agitated or irritable.
- Poor concentration: It may be difficult for the person to focus.
When checking for iron deficiency, Dr. Angove recommends including tests for the following:
- Serum iron.
- Total iron binding capacity (TIBC).
- Iron saturation.
- Complete blood count (CBC).
How to Optimize Iron Levels
There are two dietary iron types: heme iron in animal products like meat, seafood, and poultry, and non-heme iron in plant foods like beans, greens, and fortified grains.
“While we absorb the heme iron found in animal products more efficiently, we can increase our absorption of non-heme iron by pairing it with a source of vitamin C, such as citrus fruits, strawberries, kiwi, or bell peppers,” registered dietitian Laura Kauffman told The Epoch Times.
Iron supplementation is often recommended for deficiency (ferritin under 25 ng/mL) or pregnancy but can cause gastrointestinal issues like abdominal pain and constipation. To avoid them, Dr. Angove recommends hydrolyzed whole protein chelate iron supplements.
Foods rich in iron are also an option.