Is Your Breast Milk Raising or Lowering Your Baby’s IQ?

Systems Thinking and Nutrition

In this article, as in my previous article What If Cognitive Gaps Could Be Closed With Nutrition?, I will continue to explore how systems thinking can deepen our understanding of the layered challenges facing the Black community, and how the significant contributory role that diet—particularly dietary fatty acid consumption—plays in cognitive development, inflammation, and long-term wellbeing.

Why Linoleic Acid and DHA Matter

Linoleic acid (LA) is a long-chain omega-6 polyunsaturated fatty acid found in high concentrations in seed oils such as sunflower, rapeseed (canola), soybean, and corn oil. Growing evidence is implicating a high omega-6 to omega-3 ratio with poor health and cognitive outcomes. This may be especially true for Black individuals who are more likely to carry a genetic variant that makes a high intake of LA more inflammatory for them.

The FADS Gene and Inflammation in Black Women

That genetic variant involves the FADS1 and FADS2 genes, which regulate the conversion of dietary LA into arachidonic acid (AA), a precursor to pro-inflammatory compounds. Studies have shown that people of African ancestry are more efficient at this conversion, which means that when they consume a diet high in LA—as is typical in Western food environments—they produce more AA and thus may experience more inflammation. To make matters worse, LA and DHA (an omega-3 fatty acid critical for brain and nervous system development) compete for the same enzymes. In a high-LA, low-DHA diet, as is often the case with processed, seed-oil-heavy foods, LA effectively “crowds out” DHA. This is especially problematic for Black women, who may end up with high levels of LA and AA and low levels of DHA—the worst possible combination. This imbalance leads to increased inflammation, reduced DHA availability to the brain and breast milk, and potentially serious consequences for maternal and infant health—spanning physical, cognitive, and emotional development.

Breast Milk, Cognitive Development, and Country-Level Impact

There is compelling evidence that a maternal diet high in LA can alter the mother’s plasma lipid composition, which in turn influences both the fatty acid profile of her breast milk and the infant’s plasma lipid profile (Innis, 2014; Furse et al., 2019). This is significant because the lipid composition of breast milk has been shown to predict test scores in mathematics, reading, and science across 28 countries (Lassek and Gaulin, 2014). In that study, LA was negatively associated with all test scores, while DHA was positively associated. The researchers concluded that the DHA content of breast milk was the single best predictor of math performance: the higher the DHA, the higher the test score. The second strongest predictor was LA content—more LA was associated with lower scores. Remarkably, the average fatty acid profile of breast milk in each country was a better predictor of average cognitive performance than the country’s GDP or per-student education spending. This does not mean economic factors are unimportant; rather, the best academic performance was found in children who benefited from both economic well-being and a favorable diet—but among the two, diet had the greater impact.

Breastfeeding Disparities and Their Implications

Additional epidemiological studies support this link. Higher levels of LA in maternal colostrum have been associated with lower motor and cognitive scores in children at ages 2 and 3 (Bernard et al., 2015), and again at ages 5 and 6, higher LA correlated with lower intelligence scores (Bernard et al., 2017).

Breastfeeding itself is a key part of this equation, and disparities exist here too. CDC data shows that breastfeeding initiation rates are lower among Black mothers (73.6%) compared to the national average (84.1%) (CDC, 2021). By six months, only 44.7% of Black infants are still being breastfed, compared to 62% of White infants (SAGE, 2022). These disparities may limit the exposure of Black infants to the cognitive benefits of DHA-rich breast milk and increase exposure to the negative effects of LA-heavy alternatives, particularly if formula or weaning diets are high in seed oils.

DHA Deficiency and Cultural Dietary Patterns

In the U.S., roughly the same proportion of Black (22.6%) and White (18.7%) individuals consume more than two portions of seafood per week, but both lag behind Asians (41.2%)—a group that tends to achieve the highest academic attainment (Terry et al., 2018). However, the type of fish matters. Black Americans tend to consume more lean fish (e.g., cod, haddock) rather than oily fish (e.g., salmon, mackerel, trout), which are richer in DHA. Compounding this, the fish is often fried—typically in seed oils—leading to DHA loss during cooking (Nahab et al., 2010), and a corresponding increase in LA intake.

Obesity, Milk Composition, and Temperament

Obesity is another relevant factor, as it has been shown to alter breast milk lipid composition. Infants of overweight or obese mothers who breastfeed are more likely to have a higher waist-for-length, lower length-for-age, and lower head circumference-for-age compared to those of mothers at a healthy weight (Ellsworth et al., 2020). This is especially relevant because obesity disproportionately affects Black adolescent girls in both the U.S. and the UK. In the U.S., 42% of Black adolescent girls meet or exceed the criteria for being overweight, and alarmingly, 95% of those with obesity in adolescence remain obese into adulthood (Winkler et al., 2017).

The consequences of all this extend beyond physical health. The composition of breast milk can even influence infant temperament. For example, low DHA levels in breast milk are associated with higher negative affectivity—defined as a tendency toward negative emotions like fear, anger, and nervousness (Hahn-Holbrook, Fish, & Glynn, 2019). This is a sobering reminder of how profoundly maternal nutrition can shape not just physical and cognitive development, but personality as well.

InflammaFree: A Simple, Science-Backed Solution

In the struggle for equality, Black leaders have seldom prioritised nutrition as a fundamental enabler in this quest. But recent research suggests this is a critical oversight. Only by rejecting the industrialised, ultra-processed foods that cause widespread metabolic and immune dysfunction—particularly among Black populations—and instead embracing a natural, whole-food diet, can Black communities truly thrive and reach their full potential.

This is precisely why I created InflammaFree—a carefully formulated blend of high-polyphenol extra virgin olive oil and sustainable algal DHA oil. It delivers a balanced 1:1 omega-6 to omega-3 ratio, which is virtually impossible to achieve through typical store-bought oils. By combining DHA and LA in the right ratio, InflammaFree helps prevent LA from crowding out DHA, ensuring both fats can be properly metabolised and delivered where they’re needed most. Unlike fish oil capsules, it’s delicious, easy to incorporate into meals, and ideal for those who favour a plant-based diet. InflammaFree was born out of a personal need to provide something I could confidently give to my own family—knowing it supports cognitive health, maternal wellbeing, and long-term inflammatory balance. Visit InflammaFree.com to learn more.