Ultra-processed foods - the packaged snacks, sugary drinks, and ready meals that make up roughly half the calories in the average American diet - have been tied to a long list of health problems. A new review turns the question to pregnancy, and finds the association reaches the next generation [1].
The review, led by López-Yerena and colleagues and published July 17 in the journal Nutrients, pooled 84 studies on maternal diet [1]. It found that high intake of ultra-processed food during pregnancy and early childhood was consistently associated with worse outcomes for both mother and child: excessive gestational weight gain, gestational diabetes, and preeclampsia in mothers; higher obesity risk, worse cholesterol profiles, and poorer verbal functioning in children aged four and five [1].
The caveat is the most important line in the paper, and the authors put it there themselves. These are observational studies, which means they show that heavy ultra-processed diets and these outcomes travel together - not that the food causes the outcomes [1]. Diet correlates with income, stress, and access to health care, any of which could drive part of the association. 'Associated with' is not 'causes,' and the review is careful to say so [1].
What the review does establish is the consistency of the signal across a large body of research, which is itself worth knowing [1]. Ultra-processed food is not a fringe part of the diet; it is the majority of it, for many people, including many pregnant women [1]. A finding that heavy consumption tracks with worse pregnancy and early-childhood outcomes across 84 studies is a strong reason to study the link harder - and a weak reason to panic about any single meal [1].
