Researchers ran a randomized trial with 24 families in Austin. Over a 25-day period, the team provided nutritionally balanced meals that were the same except for the main protein: whole-food beef or an ultra-processed plant-based substitute.
Total fat in the meals stayed the same, but the types of fat in breast milk changed. Mothers who ate the plant-based substitute had lower long-chain polyunsaturated fatty acids and higher saturated fats from tropical oils. The study, published in the American Journal of Clinical Nutrition, found these shifts in about six days.
The trial did not test long-term infant health, and the short diet period likely would not cause lasting differences for the infants in this study.
Difficult words
- randomized trial — a study where people are put into groups by chance
- nutritionally balanced — having the right amounts of important nutrients
- ultra-processed — made with many industrial ingredients and steps
- polyunsaturated fatty acid — a fat with many double chemical bondspolyunsaturated fatty acids
- saturated fat — a fat with few or no double bondssaturated fats
- breast milk — milk produced by a mother for her baby
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- Would you change your diet while breastfeeding after hearing this study? Why or why not?
- Which part of the meals stayed the same during the trial?
- Do you think a short study can show long-term effects on infants? Why?
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