Iron and Brain Function

You’ve heard that iron is a nutrient critical for energy, but did you know it’s not just your heart or other muscles that need iron to be energized? Your brain’s cells, called neurons, demand considerable amounts of iron too. Our brains use iron to power many important tasks, including making new neurons, adding a protective myelin coating to axons (long neurons), developing synapses (spaces where the neurons communicate), and synthesizing neurotransmitters (chemical messengers used for that communication).

The importance of iron for these tasks makes the brain sensitive to changes in iron balance, also called iron homeostasis. Levels need to be in a perfect balance so that our minds and moods are stable. Levels of iron in your brain are maintained by taking iron from your blood. Iron in your blood is allowed to flow through the blood-brain barrier, into the protected inner circle of the brain’s circulation. Scientists hypothesize that endothelial cells (cells that line our blood vessels) regulate entry of iron into the brain by acting as gatekeepers for iron and releasing it when required.

Because the source of iron for the brain through our adult life is our bloodstream, brain iron status is directly affected by the quality of our nutrition and our overall iron levels. Having deficient levels of iron in our bodies, (with or without anemia) is associated with short and long-term impacts on our mental function, mood, and behaviour. Studies have concluded that iron deficiency can lead to defects in cognitive functions and the ability to pay attention, while “higher serum iron concentrations were inversely associated with cognitive impairment”. Clearly iron is essential for the brain.

On blood tests, hemoglobin levels, which are impacted by iron status, are correlated with intellectual performance in young children, teens and adults, and folks that do not have optimal levels of iron and ferritin are more likely to be diagnosed with ADHD. There is some indication that when iron metabolism isn’t right, it can affect the brain’s prefrontal cortex in both structure and function. Additionally, a review of iron studies “suggests that iron status and anemia may be associated with academic performance in some contexts and that iron supplementation during adolescence may improve school performance, attention, and concentration.”

Iron is required in just the right balance across the lifespan. Iron deficiency is prevalent in early childhood, when the brain particularly needs the right amount of iron to support rapid growth and development, however, an elevated risk for iron deficiency can happen in other phases of life too. In adolescents, iron-deficiency anemia is the leading cause of disability-adjusted life years lost, and cognitive and behavioural symptoms have been reported in iron-deficient women of reproductive age, in part due to menstrual blood loss.

During pregnancy, iron requirements increase significantly, and low iron levels may be associated with symptoms of “baby brain” in the mom. Iron is needed by dividing cells in the womb, and a deficiency at this point of development can lead to impaired neurons in the baby. Iron is a cofactor of ribonucleotide reductase, which is responsible for an important step in the synthesis of DNA. That makes iron essential for cell division and forming of the nervous system. Impaired or iron-deficient neurons are not as good at enabling brain communication.

Iron deficiency impacts mental, emotional, and motor function by affecting the brain’s ability to make the enzymes involved in releasing neurotransmitters to pass messages between neurons. We need iron to produce these neurotransmitters, including serotonin (our happy hormone) as well as dopamine (our feel-good hormone). We even need it to make noradrenaline (which is needed for our stress response) and monoamine oxidase (an enzyme that helps break down these neurotransmitters as needed so that we maintain the perfect amount and balance of them).

Having the right balance is key. When your serotonin levels are healthy, for example, you’ll feel happier, focused, and calmer. Too much can leave you feeling nervous or agitated, and too little can leave you feeling sore, forgetful, craving sweets at night, or even depressed. When it is time to make or to degrade serotonin or other neurotransmitters, if the brain falls short of its iron requirements, that can contribute to behavioural issues, mental impairment, anxiety, or depression.

Getting all the nutrients you need through your diet and via supplementation can protect your mental health – both your mood and your cognition. Various tests have shown the importance of including the right balance of minerals like zinc, iron, copper, and selenium, since not doing so can impact cognitive performance. It is easy to see that you want to get enough iron – but in a reasonable and safe dosage like what would be found in a healthy iron-rich diet, in the double, not the triple digits of milligrams daily.

So how much is enough? The bare minimum adult men need to be healthy is 8 mg daily, and most young adult women need 18 mg. If you are deficient, you’ll need to get a bit more. Flora’s Ferritin+ provides 20 mg of iron per capsule, the perfect amount to bump you out of deficiency without risk of overload. Because it is recognized by the ferritin receptors in your endothelial cells, they control intake of the iron into your cells, making it exceptionally safe. Taking iron has never been so comfortable!