This study was published in Paediatric and Perinatal Epidemiology 2012 Mar;26(2):163-75
Study title and authors:
Early-life soy exposure and age at menarche.
Adgent MA, Daniels JL, Rogan WJ, Adair L, Edwards LJ, Westreich D, Maisonet M, Marcus M.
Department of Epidemiology, Gillings School of Global Public Health, UNC-Chapel Hill, Chapel Hill, NC, USA. firstname.lastname@example.org
This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/22324503
The commencement of menstruation at puberty is termed as menarche. It marks the beginning of reproducive life of a women. Early menarche is linked to increases in conditions such as breast cancer, heart disease, asthma and of course unwanted attention from older males.
The study investigated the effects soy-based infant feeding had on the timing of menarche. The study included 2,920 girls who were followed for 14.5 years.
The study found, compared with girls fed non-soy-based infant formula or milk (early formula), early soy-fed girls were at 25% higher risk of menarche throughout the course of the study.
The author of the study, Dr Margaret Adgent from the National Institute of Environmental Health Sciences, concludes: "Our results suggest that girls fed soy products in early infancy may have an increased risk of menarche specifically in early adolescence. These findings may be the observable manifestation of mild endocrine (hormonal)-disrupting effects of soy isoflavone exposure".