The story in detail
Human milk contains metabolic hormones as well as nutrients. Researchers studied 55 adolescent mother–infant pairs, measuring maternal body composition, blood and milk hormones, and infant growth. Maternal fat mass was associated with leptin in blood and milk. Milk leptin and ghrelin related to some infant measurements, while adiponectin did not show the same pattern.
This small observational study cannot demonstrate that a milk hormone directly causes a growth difference. Timing and other nutritional factors may contribute, and findings from adolescent mothers cannot automatically represent all mothers. The work helps describe biological variation in milk. It does not justify labelling someone’s milk as good or bad, stopping breastfeeding or attempting to manipulate hormone levels.
Study date: 2026-07-21 · Story: 20 October 2026
What was found?
In postpartum data from 55 adolescent mothers and their infants, maternal fat mass was associated with leptin in blood and milk. Higher milk leptin was associated with shorter infant length.
What does it mean?
The study explores links between biological signals in milk and characteristics of mothers and babies.
Limitations
This small, cross-sectional secondary analysis cannot establish causality. One morning milk sample cannot represent an entire breastfeeding period. The findings do not recommend reducing breastfeeding or maternal weight loss.
Sources and review scope
Original article (DOI) · Reviewed source 1
The original article abstract, methods and relevant results were checked.
Sources last checked: 20 October 2026.
Editorial expansion: 21.10.2026
Keep this story
Feedback to the editor
Only the editor can read this; it is not a public comment. Do not include personal health information.
Sign in to send feedback