New research links higher intake of ultraprocessed foods to a measurable reduction in brain volume among children under six, raising concerns about dietary habits during a critical period of development.
Study details and key findings
The investigation, conducted by a team at Children’s Hospital of Los Angeles, followed 144 Latino/Hispanic mother‑child pairs from age two through six. Researchers used magnetic resonance imaging (MRI) to assess subcortical brain regions—specifically the accumbens, amygdala, pallium, putamen and thalamus—when the children reached six years old.
Children whose diets included a ten‑percent higher proportion of ultraprocessed foods showed an almost two‑percent decrease in the volume of those subcortical structures. The study did not find a direct link between this structural change and performance on cognitive tests administered at ages two and six, which measured motor skills, language ability, memory, attention and comprehension.
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“What children eat early in life may shape brain development in ways that we are just beginning to understand,” said Michael Goran, senior author of the study, in an interview with TheDoctor.
Implications for early childhood nutrition
Ultraprocessed foods—such as many fast‑food items, frozen meals, baked goods and lunch meats—typically contain refined sweeteners, flavorings and preservatives, while offering few whole ingredients or essential nutrients. These products often appeal to children because they are high in sugar and sodium, which can create cravings and drive consumption.
In the United States, more than half of the calories consumed by children aged one to five come from these highly engineered foods. Early childhood is a sensitive window for brain growth, and the study suggests that exposure to such diets may alter the physical architecture of regions involved in reward processing, emotion and motivation.
Although the investigators reported no observable effect on the children’s cognitive test scores, Goran noted, “Even without changes in cognitive performance, we are seeing measurable differences in brain structure.” This observation aligns with a recent Canadian study that linked high ultraprocessed food consumption to later emotional and behavioral issues in preschoolers.
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Parents are encouraged to prioritize whole foods—fresh fruits, vegetables and minimally processed items—while limiting ready‑to‑eat meals, frozen dinners and sugary beverages. Substituting diluted fruit juice or water for sodas and sports drinks may also reduce exposure to excessive sugars and additives.
From a broader perspective, the findings highlight how dietary patterns established in early years can have lasting physiological effects. While the study focused on a specific demographic, the underlying mechanisms—altered brain structure without immediate functional decline—could be relevant to other populations as well.
The research appears in The American Journal of Clinical Nutrition.
