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Some infants are fed soya-based infant formulas, which are known to contain high levels of phytoestrogens. It is possible that phytoestrogens may affect the health of infants fed soya-based infant formulas. The project aims to examine the effects that one phytoestrogen (an isoflavone) has on post-natal development in rats.
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This project will investigate the effects of an isoflavone found in soya-based infant formula on a range of male and female developmental parameters in an experimental model of human neonatal exposure.
Results and findings: When administered at a level similar to that given to human infants fed soya-based formulas, the isoflavone genistein had no effects on female sexual development. However, when a dose ten times higher than this was used, female sexual development began at an earlier time-point in the rats. The implications of this finding for humans in unclear because of the difference in sexual development between rats and humans.
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Genistein had no similar effects on male sexual development, even at the higher dose.
<p>Find more about this project and other FSA food safety-related projects at the <a href="http://www.food.gov.uk/science/research/" target="_blank">Food Standards Agency Research webpage</a>.