By Krista Maas de Villiers, BSc Dietetics, Founder of Nunona
Mom brain isn't a punchline. It's a structural adaptation. And what you feed it changes everything.
You're mid-sentence and the word is just gone. You've checked the same list three times. Your brain feels like it's running every application at once, nothing loading quite fast enough. If you've been pregnant or postpartum, you know this feeling. You've probably laughed it off as mom brain. But what if the fog isn't a failure? What if it's a sign that your brain is doing something remarkable?
Mom brain is real. But it's not what you think.
For years, "mom brain" sat in the same drawer as "pregnancy glow," a soft, slightly condescending way to describe something women experience but science had not fully explained. Then the research arrived.
A landmark 2017 study published in Nature Neuroscience found that pregnancy produces measurable reductions in gray matter volume in regions associated with social cognition, self-referential processing, and theory of mind.
That sounds alarming. It isn't. The same research showed that these changes were highly targeted: the brain was pruning and reorganizing, not shrinking indiscriminately. The regions that changed are precisely those involved in reading other people's emotional states, detecting social threats, and building secure attachment. The brain was preparing for motherhood. A 2022 follow-up found the changes persisted for at least two years postpartum and were associated with stronger maternal bonding.
This is not cognitive decline. This is cognitive investment.
A brain in adaptation needs serious fuel
Structural reorganization at this scale doesn't happen on fumes. The maternal brain has elevated nutritional requirements, and three nutrients are especially central.
DHA is a structural component of gray matter and a primary building block of fetal brain tissue. A daily intake of 200mg is supported by evidence for fetal brain development and for reducing the risk of postnatal depression.
Iron supports oxygen delivery to brain tissue and is directly tied to cognitive energy. Iron deficiency during the perinatal period is one of the most common contributors to fatigue-related brain fog: the kind that makes concentration feel like physical effort.
B vitamins (particularly B6, B12, folate, and choline) support neurotransmitter synthesis, methylation, and mood regulation. Choline is a precursor to acetylcholine, the neurotransmitter most associated with memory and learning. Choline requirements during lactation are higher than at any other point in a woman's life.
The cognitive labor no one measures
Layer this on top of what researchers have termed cognitive labor: the invisible, ongoing mental work of tracking, planning, anticipating, and managing that falls disproportionately on mothers. Studies suggest women carry an estimated 73% of household cognitive labor, the running list of what needs to happen, when, and for whom.
This isn't a side note. It's an additive load on a brain that is simultaneously remodeling itself, growing or nourishing a human, and recovering from birth. The cognitive cost of motherhood isn't incidental. It's structural. What the body needs in response to that demand is equally structural: consistent, real-food nutrition that supports the brain at a cellular level.
Fueling the adaptation
The fog is real, and so is the science behind it. But adaptation doesn't run itself. The gray matter reorganization, the elevated choline demands, the DHA your body is pulling toward fetal brain tissue and your own neural function: all of it requires resources. When those resources are undersupplied, the adaptation still happens. It just costs more.
This is where nutrition becomes an active input, not a passive one. Mama Bites delivers 200mg DHA, iron, B vitamins, and choline in a real-food format, alongside the protein and healthy fats that support blood sugar regulation and sustained cognitive energy. Not because the maternal brain is broken. Because it is working at a level that deserves to be met with the same intention it is bringing to the work.
The fog isn't a sign that something went wrong. Fueling it well is how you make sure it goes right.
About the Author
Krista Maas de Villiers, BSc Dietetics, is the Founder & CEO of Nunona, a modern nutrition platform supporting maternal and infant health across the first 1,000 days—from preconception through postpartum and baby’s first foods.
Nunona launched with a first-of-its-kind real-food pre+postnatal vitamin designed to improve absorption, reduce nausea, and deliver meaningful outcomes for both moms and babies.
Backed by experts in science, nutrition, and consumer health, Nunona aims to bridge the gap between research and real life—translating complex nutritional science into accessible, effective solutions for modern families.
References
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2. Hoekzema E, van Steenbergen H, Strauss M, et al. Maternity and the maternal brain: persistence of structural changes at 2 years postpartum. Nat Commun. 2022;13(1):2972. doi:10.1038/s41467-022-29769-1
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5. Georgieff MK. Iron deficiency in pregnancy. Am J Obstet Gynecol. 2020;223(4):516-524. doi:10.1016/j.ajog.2020.03.006
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7. Walters KL, Bhatt DL, Bhardwaj A, et al. The invisible load: cognitive labor and its distribution in dual-income households. J Marriage Fam. 2019;81(4):907-923.
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