"Research is now showing that when you feed your baby soy formula, you're giving him or her the equivalent of five birth control pills a day" ...
Breastfeeding has always been the main culprit. However, this is a `longitudinal' study reported in the JAMA (JAMA. 2001;286:807-814).:
Design, Setting, and Participants Retrospective cohort study conducted from March to August 1999 among adults aged 20 to 34 years who, as infants, participated during 1965-1978 in controlled feeding studies conducted at the University of Iowa, Iowa City (248 were fed soy formula and 563 were fed cow milk formula during infancy).
Main Outcome Measures Self-reported pubertal maturation, menstrual and reproductive history, height and usual weight, and current health, compared based on type of formula exposure during infancy.
Results No statistically significant differences were observed between groups in either women or men for more than 30 outcomes. However, women who had been fed soy formula reported slightly longer duration of menstrual bleeding (adjusted mean difference, 0.37 days; 95% confidence interval [CI], 0.06-0.68), with no difference in severity of menstrual flow. They also reported greater discomfort with menstruation (unadjusted relative risk for extreme discomfort vs no or mild pain, 1.77; 95% CI, 1.04-3.00).
Conclusions Exposure to soy formula does not appear to lead to different general health or reproductive outcomes than exposure to cow milk formula. Although the few positive findings should be explored in future studies, our findings are reassuring about the safety of infant soy formula.
You might want to bookmark the following as I expect the outcomes will be posted up before Christmas (latest and greatest):
Effects of Infant Diets on Estrogen Activity and Development :
http://clinicaltrials.gov/ct2/show/NCT00340665
To access the GAM Nutrient Requirements of Poultry 9th edition (free to read online at the NAS):
http://www.nap.edu/catalog.php?record_id=2114
(not taking any position beyond opining that soylent green was probably a well balanced ration
) ME
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