Iron levels linked to reduced brain fog during menopause

Iron levels linked to reduced brain fog during menopause | Image Credit: © Єгор Городок - © Єгор Городок - stock.adobe.com.

There is a link between iron levels and experiencing brain fog during the menopause transition, according to a recent study published in Nutrients.¹

According to the data, cognitive performance is improved among women with adequate iron levels during the menopausal transition. Additionally, unsafe iron levels in the brain, which have been linked to Alzheimer’s and other neurodegenerative disease risks, are not equivalent to sufficient iron in the blood.

“When a woman makes the menopausal transition, she’s no longer losing blood on a monthly basis, which means she’s no longer losing iron,” said Michael Wenger, PhD, lead author and professor of psychology at the OU College of Arts and Sciences.

Measuring characteristics and iron biomarkers

Initial data was collected through an online survey and included age, self-reported body mass index, English proficiency, iron supplementation use, menopausal symptoms, and depression.² Afterward, trained phlebotomists collected blood samples to determine blood iron levels and menopausal status.

Relevant measurements included hemoglobin (Hb), serum ferritin (sFt), mean corpuscular volume (MCV), red blood cell count (RBC), C-reactive protein, white blood cell count, hematocrit (HCT), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), and red blood cell distribution width (RDW).

Magnetic resonance imaging was also performed to measure iron concentrations in the brain. Regions of the brain assessed included the caudate nucleus, globus pallidus, substantia nigra, ventrolateral prefrontal cortex, putamen, and anterior cingulate.

Cognitive function was determined through 4 tests. These included a face/name associative memory task, probabilistic selection task, rule-based category learning task, and visuospatial working memory task. Electroencephalographic (EEG) measures were collected concurrently.

Participant characteristics and sFt levels

Participants were aged a mean 53.96 years, with 92.6% self-reporting as Caucasian. Measurements indicated participants were above the research criteria for iron deficiency, with a mean sFt of 61.90 ng/mL.

Additionally, the mean sFt percentile of 40.31 indicated that patients had iron levels below what was expected for their race and ethnicity. The overall study population was not anemic, with a mean Hb of 13.66.

Link between iron parameters and cognition

The sFt percentile had the most significant link with behavioral variables, with higher values of sFt percentile indicating increased levels of performance. This included increased accuracy, discriminability, and shorter reaction times. Similar associations were found for raw sFt values, though these weren’t as common as those for sFt percentiles.

Links to performance were also found for variables indicative of oxygen transport capability, including RBC, Hb, MCV, HCT, MCH, MCHC, and RDW. At least 1 significant association with these variables was observed for each task.

EGG measurements and brain health

For EGG values, significant associations with sFt and the sFt percentile were also reported. The sign of the correlation coefficient was consistent with the sign of the component amplitude in all correlations, highlighting higher-amplitude signals in patients with increased sFt.

Slight correlations were also reported between EGG features and biomarkers linked to oxygen transport. However, these associations were not as common as in the behavioral data. Notably, there were no correlations between higher iron status and iron levels in any region of the brain.

Conclusion

Overall, the data highlighted a relationship between systemic iron levels and cognitive performance without any link to brain iron levels. Investigators concluded that better iron status leads to improved brain function during the menopausal transition.

“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 Wegner.¹

References

1. Low iron could cause brain fog during menopause transition, OU study suggests. University of Oklahoma. April 28, 2025. Accessed May 1, 2025. https://www.eurekalert.org/news-releases/1081966.
2. Barnett AL, Wenger MJ, Miles P, et al. Cognitive performance in relation to systemic and brain iron at perimenopause. Nutrients. 2025;17(5):745. doi.org:10.3390/nu17050745