Iron Deficiency Anemia: Understanding Root Causes and Treatment Approaches

Do you find yourself exhausted despite getting adequate sleep? Are you constantly cold, even when others are comfortable? Perhaps you've noticed your hair thinning, your nails becoming brittle, or you're struggling with brain fog that makes it difficult to concentrate at work or home.

For many women, these symptoms often coincide with other health challenges like irregular or heavy menstrual periods, digestive issues like bloating and constipation, heightened anxiety, and hormonal imbalances that seem to create a cascade of health problems. You might find yourself craving ice or starch, experiencing restless leg syndrome at night, or feeling short of breath during activities that used to be effortless.

These seemingly unrelated symptoms may actually point to a common underlying issue: iron deficiency anemia. What's particularly frustrating for many patients is that they've been told their blood work is "normal," when in reality, their ferritin levels, the body's iron storage, may be dangerously low, setting the stage for more serious health complications.

Iron deficiency anemia remains one of the most common nutritional deficiencies worldwide, particularly affecting women of reproductive age. Yet its underlying causes are often overlooked in favor of simple supplementation. The reality is that effective treatment requires identifying and addressing the root cause rather than merely replacing iron stores because simply taking an iron pill rarely solves the underlying problem.

Defining Iron Deficiency Anemia vs. Low Ferritin

Iron deficiency anemia is formally diagnosed through a complete blood count (CBC) showing low hemoglobin levels, known as microcytic anemia, characterized by smaller, denser red blood cells. However, many patients present with low serum ferritin before developing frank anemia.

Ferritin serves as the body's iron storage system, functioning much like a savings account for iron reserves. Ferritin levels typically decline before hemoglobin and hematocrit changes become apparent on laboratory studies. While low ferritin without anemia may not meet the clinical definition of iron deficiency anemia, research demonstrates that patients experience similar symptoms including fatigue, hair loss, cold intolerance, and thyroid dysfunction.

Primary Cause: Blood Loss

The most significant cause of iron deficiency anemia is blood loss, which requires thorough investigation before considering other etiologies.

Menstrual Blood Loss

Heavy menstrual bleeding represents a leading cause of iron deficiency in reproductive-age women. The diagnostic workup should include:

  • Uterine fibroids assessment: Transvaginal ultrasound is essential to evaluate for fibroids, which can cause significant menstrual blood loss

  • Thyroid function evaluation: Hypothyroidism is associated with menorrhagia and should be ruled out

  • Medication review: Blood-thinning medications and supplements can exacerbate menstrual bleeding

Gastrointestinal Blood Loss

Occult or obvious gastrointestinal bleeding requires comprehensive evaluation by a gastroenterologist. Potential sources include:

  • Peptic ulcer disease

  • Colorectal polyps

  • Colorectal malignancy

  • Inflammatory bowel disease (Crohn's disease or ulcerative colitis)

Appropriate endoscopic evaluation, including colonoscopy and upper endoscopy, should be performed based on clinical presentation and risk factors.

Functional Causes of Iron Deficiency

When structural abnormalities are excluded, several functional conditions can impair iron absorption or sequester available iron.

Malabsorption Syndromes

Various gastrointestinal conditions can interfere with iron absorption:

  • Celiac disease: Autoimmune enteropathy affecting the small intestine

  • Small intestinal bacterial overgrowth (SIBO): Bacterial dysbiosis affecting nutrient absorption

  • Small intestinal methane overgrowth: Similar to SIBO but involving methane-producing organisms

Infectious Causes

  • Helicobacter pylori: This gastric infection can sequester iron even without causing peptic ulcer disease

  • Parasitic infections: While trendy in functional medicine, the evidence for parasites causing iron deficiency is nuanced

Regarding parasites, it's important to distinguish between different types. Blastocystis hominis, a commensal organism, may be associated with lower iron levels in some individuals, but causation hasn't been definitively established. True helminth infections, such as hookworm, are more clearly associated with iron deficiency and are typically endemic to specific geographic regions.

Nutritional Cofactor Deficiencies

Copper deficiency can impair iron utilization and transport within the body. However, copper supplementation requires careful consideration, as excess copper can be oxidative and may exacerbate ADHD symptoms by depleting dopamine and increasing norepinephrine levels.

Patients often experience initial improvement with copper-rich supplements like beef liver, followed by symptom deterioration over time. If copper deficiency is suspected, the focus should be on:

  • Identifying underlying causes of deficiency

  • Incorporating copper-rich foods

  • Optimizing gastrointestinal health for better absorption

  • Monitoring zinc supplementation, which can antagonize copper absorption

Treatment Considerations

Iron supplementation, while sometimes necessary, should not be the first-line approach without proper evaluation. Indiscriminate iron supplementation can:

  • Exacerbate certain gastrointestinal conditions

  • Feed pathogenic bacteria, particularly proteobacteria implicated in SIBO

  • Worsen parasitic infections if present

  • Promote inflammation through endotoxin production

Supplementation Strategies

When iron supplementation is indicated, consider concurrent administration of galacto-oligosaccharides (GOS), which may help mitigate the feeding of potentially pathogenic bacteria.

However, regardless of supplementation decisions, investigating the underlying cause remains paramount. The goal is to address the root cause so that long-term supplementation becomes unnecessary.

Conclusion

Iron deficiency anemia and low ferritin require a systematic, thorough approach that goes beyond simple iron replacement. By identifying and treating underlying causes, whether blood loss, malabsorption, infections, or nutritional imbalances—we can provide patients with lasting solutions rather than lifelong supplementation.

Effective management involves collaboration between primary care providers, gastroenterologists, gynecologists, and other specialists as needed. Only through this comprehensive approach can we truly address iron deficiency anemia and restore patients to optimal health.

Allie McLane