Folsom, Calif. – October 29, 2026 -- A handful of walnuts, about 12–14 halves, delivers 2.5 grams of plant-based omega-3 ALA, and new research links higher prenatal ALA levels to better attention in early childhood.
The study, published in the European Journal of Epidemiology and funded by the California Walnut Commission, examined how omega-3 fatty acids measured at birth related to children's thinking skills years later. It is described as the first to assess cord plasma ALA proportions against cognitive trajectories in offspring.
Researchers followed 716 mother-child pairs across Spain
Teams from IRB CatSud and ISGlobal analyzed data from the Spanish Childhood and Environment (INMA) project, a population-based birth cohort covering four regions of Spain. They measured ALA, DHA and EPA in umbilical cord plasma. Children were then evaluated at multiple points from about age 5 through 15 on attention, working memory and fluid intelligence, the ability to reason and solve new problems.
Higher ALA levels tracked with better attention and reasoning at ages 5 and 7
Children with higher ALA proportions showed significantly lower overall inattentiveness. Around ages 5 and 7, higher ALA was also associated with better fluid intelligence. Those advantages diminished over time, and the modeled associations reversed by adolescence.
A positive working-memory trajectory with higher ALA was less robust in the primary analysis. It became statistically significant only in additional sensitivity analyses.
DHA's associations extended into adolescence
Higher DHA proportions were associated with lower overall inattentiveness and better overall working memory. Working memory advantages were strongest earlier in childhood, while favorable links with attention and fluid intelligence became clearer as children approached adolescence. EPA was not significantly associated with any of the cognitive outcomes evaluated.
One ounce of walnuts supplies 2.5 grams of ALA
ALA is considered essential because the body cannot produce it and must get it from food. The body can convert some ALA into EPA and DHA, but that conversion is limited. Besides walnuts, ALA sources include flaxseeds, chia seeds and certain plant oils, while DHA and EPA are found primarily in fatty fish and seafood.
Principal investigator Jordi Julvez said the findings highlight the importance of "looking beyond omega-3 fatty acids as a single group." First author Ariadna Pinar said the work reinforces a varied, balanced diet that provides different omega-3 sources.
The authors note that further research is needed to clarify the individual contributions of each omega-3 fatty acid and how prenatal and postnatal dietary patterns influence cognitive development over time.