Iron deficiency is the most common nutrient deficiency I see in my practice. In fact, most of my menstruating female patients are iron deficient. It is so common in my female patients that I’m surprised when I don’t see this on a lab report.

Iron is necessary for the production of heme in red blood cells, a protein responsible for delivering oxygen to tissues throughout the body. Iron is critical for mitochondrial function and the production of cellular enery in the form of ATP. The brain is the most energy demanding organ in the body and therefore “feels” the effects of iron deficiency early on. In the brain, iron plays a critical role in the production of the neurotransmitters serotonin, dopamine, and norepinephrine.

With this in mind, it is easy to see why iron deficiency tends to cause psychiatric problems such as depression, brain fog, and fatigue long before it causes anemia. Lab tests for iron are not part of routine annual bloodwork. Surprisingly, these labs are usually not checked until things are really bad, when anemia is apparent on a complete blood count, a relatively late finding of iron deficiency. For this reason, many of my patients are surprised to find out they are iron deficient because they were told they didn’t have anemia.

With treatment, most people notice a boost in their energy levels quickly. Improvement to mood and cognition occur more gradually. The most common cause for iron deficiency is menstrual bleeding in the setting of inadequate dietary intake of bioavailable iron found mostly in animal protein. For treatment, I like to recommend a highly absorbable form of iron that is bound naturally to heme protein. I try to avoid conventional iron supplements that don’t get absorbed well and tend to cause intolerable constipation and abdominal pain.

When a person is iron deficient, supplementation is usually necessary. Dietary changes alone are usually not enough. Once a person reaches target levels, they can try to maintain it with dietary changes. If a person does not respond to oral supplementation or have known gut absorption issues, IV iron infusions may be necessary.

One should not take iron supplements blindly because having too much iron can be problematic too. I routinely check an iron panel and ferritin level on all patients reporting any psychiatric problem. When supplementing, we recheck ferritin levels every few months to monitor progress. Optimizing iron is low hanging fruit that is often overlooked. It’s usually only one peice of the puzzle but one that is absolutely critical in setting up a patient for long term success.