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Investigation of the Post-Natal Developmental Toxicity of an Isoflavone


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.
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.

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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.
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="; target="_blank">Food Standards Agency Research webpage</a>.

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