By: Dr. Colin O’Brien ND, Medical Director, Cyto-Matrix
Every healthcare practitioner should be able to rhyme off the keynote symptoms of iron-deficiency: fatigue, weakness, dizziness and pallor (pale skin) probably come to mind first. This makes sense given that iron is the most commonly deficient nutrient in the world and a concern often seen in private practice. But the implications of suboptimal iron extend much further than low hemoglobin and low energy. Iron is needed for so much more.
Many practitioners, myself included, have likely missed opportunities to successfully treat patients with iron restoration therapies over the years because of more “atypical” signs and symptoms of inadequate iron. Yes, iron is classically needed in hemoglobin formation and, therefore, oxygen delivery and energy levels, but here are some other conditions and physiological functions that may warrant a more thorough exploration of iron levels:
Restless Leg Syndrome (RLS): Iron deficiency has been found to be a common cause of RLS occurring in about 25% of cases! Supplemental iron is certainly most effective in those with documented iron deficiency, however, some patients respond to iron supplementation even without anemia. Iron is thought to be beneficial for RLS through its ability to upregulate dopamine synthesis (it is needed to convert tyrosine into dopamine). If the RLS is refractory to iron therapy, consider deficiencies of magnesium, B12 and vitamin E instead.
Female Infertility: Case reports have found that iron supplementation resulted in pregnancy within 28 weeks in infertile woman with borderline low ferritin levels (14-40 ng/mL). Certainly, this is not to say that iron is the ‘silver bullet’ for female infertility, but it deserves attention amidst all other factors.
Diffuse Hair Loss: General hair loss can be a symptom of iron deficiency, even before anemia sets in. Restoring optimal iron levels has been shown to offset this symptom and iron supplementation can also be useful in cases of brittle, dry and splitting hairs (if you’re having compliance issues with iron supplements in iron-deficient female patients, this may be worth mentioning!)
Poor Immune function: Iron is needed for proper immune function through cytokine production in macrophages and an iron-deficient state may lead to an insufficient immune response. For example, one study in individuals with oral candidiasis found that iron restoration led to lower salivary candida counts and reduced oral lesions.
Thyroid Function: We classically discuss the need for selenium to convert T4 into the more bioactive T3, but iron is another mineral that is necessary to promote this conversion through deiodinase activity (and iron is also needed for thyroid peroxidase action). To make matters worse, low thyroid function can lead to worse iron absorption. In cases of hypothyroidism with concomitant iron deficiency, combination treatment with iron and levothyroxine has been shown to be superior over each therapy alone.
Menorrhagia (heavy menstrual bleeding): Substantial blood loss can obviously lead to iron deficiency. However, few people are aware that an iron deficiency can actually cause a recurring state of heavy menstrual bleeding through weakened uterine muscles that cannot properly clamp down on blood vessels (iron is a cofactor for cytochrome oxidase, an enzyme necessary for muscle contraction). Ultimately, interventional trials confirm that iron supplementation is necessary not only for symptom control but also to reduce the heavy bleeding itself.
Cognition, Mood & Intelligence: It is well-documented that children and adults perform poorer on mental function tests in states of iron deficiency, with areas such as attention, memory and concentration being affected. This is the case even in the absence of outright anemia. Mechanistically, inadequate iron supply leads to a dysregulation of dopamine and serotonin metabolism. Both animal trials and human studies have shown that severe iron deficiency during infancy may have long-standing implications on brain health that persist well into adulthood, regardless of adequate iron intake later on in life.
As clinicians, it is easy to start down a rabbit-hole to find a medical explanation for complex issues. Yet, it’s generally best to follow the principle of ‘Occam’s razor’: the simplest solution is typically the correct solution. If a patient is vegan, has heavy bleeding or any of the conditions listed above, get back to the basics and test their hemoglobin, ferritin and other blood markers. A well-absorbed iron might be the simple answer that you and your patients are looking for.
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