Iron and the Brain: A Missing Link in Midlife Brain Fog

Even women with normal blood counts may experience brain fog if iron levels aren’t optimal.

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Iron is present in every cell of the body, including the brain, so it is necessary for many functions related to cognitive health. A study found that having sufficient levels of iron in the blood during perimenopause—the transition from having a monthly menstrual cycle to having no cycle—was associated with better cognitive performance. While the women in the study didn’t have iron deficiency, quite a few had suboptimal levels for their age, which impaired memory and attention.

Animal foods are rich in iron, but some plant foods are also good sources.

Low Iron and Mental Fog

The study, conducted at the University of Oklahoma and published in Nutrients, involved perimenopausal women who were not anemic and had either low or normal iron levels. Participants provided blood samples to measure iron and performed cognitive tests while undergoing an electroencephalogram (EEG) and a magnetic resonance imaging (MRI) scan to estimate iron levels in the brain. Results showed that higher blood iron levels were associated with better cognition and stronger EEG signals.

“Our previous research has shown that being iron-deficient extracts some serious costs in terms of cognitive performance,” said Michael Wenger, a professor of psychology at the University of Oklahoma College of Arts and Sciences and lead author of the study, in a statement.

“If I were to give a woman with iron deficiency a simple task in which she presses a button every time an asterisk appears on a screen, the deficiency would cost her about 150 milliseconds. That doesn’t sound like a lot, but we make simple decisions like that when we choose every word we say in a sentence. Those 150 milliseconds add up.”

This research, together with the current findings, points to the importance of iron in mental functions.

“Low iron could easily be one of the reasons that a woman is experiencing brain fog during the menopausal transition.”

Iron Accumulation in the Brain

The benefit-to-risk ratio of iron depends on where it accumulates in the body. While normal iron levels in the blood are linked to optimal cognition, iron accumulation in the brain is linked to cognitive decline.

The researchers were concerned about the iron accumulation that occurs as people age. In addition to cognitive decline, it is thought that iron buildup in the brain can contribute to neurodegenerative conditions such as Parkinson’s and Alzheimer’s diseases. For this reason, the authors considered whether correcting low iron levels in perimenopause to enhance cognition would have the highly negative side effect of increasing iron accumulation in the brain.

However, MRIs of the brain did not show a relationship between blood iron levels and brain iron levels. This means that women who increase their intake of iron-rich foods during perimenopause have no risk of adding to harmful brain iron buildup.

“This data was surprising, and good news because it appears that having iron levels that are at or above what you should expect for your age does not mean you’re accumulating more iron in your brain,” said Wenger in the statement.

How Iron Affects Cognition

Exactly what is it about the functions of iron that can affect cognition? The Epoch Times put the question to Wenger, who noted that iron is the most abundant metal in the body and in the brain, and it plays the following roles in cognition:

• Iron is critical for forming myelin, a substance that acts like shielding on a cable and helps speed signals along nerve fibers.
• Iron is vital for synthesizing and regulating neurotransmitters—the chemicals that communicate signals between nerve cells—including dopamine and serotonin.
• Iron is necessary for creating new nerve cells and synapses, the points of communication between them.
• Iron is essential for helping nerve cells expend energy, as it supports oxygen transport throughout the body and brain.

Iron Supplements Versus Dietary Iron

The National Institutes of Health (NIH) reports that iron can be harmful if people get too much from a dietary supplement. High doses can cause symptoms such as nausea, vomiting, diarrhea, constipation, and abdominal pain, especially when taken on an empty stomach. Excess iron can also cause more serious effects, such as inflammation of the stomach lining and ulcers. Extremely high doses can result in organ failure, convulsions, and death.

There is little likelihood of having an overdose of iron if it is obtained through food rather than supplements, the NIH reported.

“Nutritionists always say to increase iron intake with food rather than with supplements due to the somewhat nasty effects iron supplements can have on the gut,” said Wenger in an email to The Epoch Times. “If a woman has suboptimal iron levels, and she makes some simple changes in her diet, she could be back at more optimal levels within three months.”

How to Boost Iron Intake

Food sources of iron include:

• Iron-fortified breakfast cereals and breads
• Lean meat, poultry, and seafood
• Kidney beans, spinach, white beans, peas, and lentils
• Nuts and some dried fruits, such as raisins

“Based on current guidelines, women in perimenopause need about 18 milligrams of iron per day,” said Vandana Sheth, a registered dietitian nutritionist, in an interview with The Epoch Times. “Being intentional with iron intake can help.”

She provided the following examples of how women can boost their iron intake.

For those who include poultry or seafood in the diet:

• A 3-ounce serving of roasted chicken thigh provides about 2.1 milligrams of heme iron, a highly absorbable form. Pair it with a side of sautéed spinach for a further boost of overall iron intake.
• A 3-ounce serving of baked salmon provides about 0.7 milligrams of iron, along with healthy omega-3 fatty acids that support brain health.
• A 3-ounce portion of cooked oysters offers around 5 to 8 milligrams of iron.

Since the iron from plant sources is not as bioavailable as that from meat, it’s a good idea to eat these foods with a source of vitamin C to enhance absorption.

For vegetarians:

• A bowl of iron-fortified cereal is a rich plant source, as many varieties provide between 8 to 18 milligrams of iron per serving. Pair it with a small glass of orange juice to boost absorption.
• A hearty chickpea and quinoa salad combined with tomatoes, bell peppers, or a squeeze of lemon provides 5 to 6 milligrams of iron and a vitamin C boost.
• A tofu stir-fry made with half a block of firm tofu offers about 3 to 4 milligrams of iron. Include vitamin C-rich vegetables such as bell peppers and broccoli.