Background Children in industrialized and developing countries have a higher tendency to present earlier signs of puberty. One hypothesis includes the hormonal effects of phytoestrogens found in soy products.
Objective to examine the association between consumption of soy-based food in early infancy and childhood and the incidence of early or precocious puberty and overweight in school-aged children.
Methods the study population for this case control study was randomized from a prospectively followed cohort of all babies born at Assaf Haroffeh Medical Center and followed for milk allergy signs and food intake until the age of 3 years (A nested cohort). It was divided to those who were allergic to milk, and thus consumed only soy-based formula and food during infancy and childhood (soy group) and a randomized control group who consumed a non-soy based formula . For both groups, food habits data were available during infancy and collected from 3 days food diaries during the current study. Physical examination, including weight, height, blood pressure and Tanner Pubertal Staging were performed.
Results Study population included 89 participants, 29 in the soy group. Mean age was 8.5±0.64 years, 45 males. There was no association between soy consumption in infancy and early or precocious puberty and overweight.
Conclusions This is the first prospective long term follow up study of a milk allergy proven cohort and a randomized control group, indicating there is no association between infantile soy consumption and signs of early or precocious puberty, and overweight.
