Interesting that we ignore the physical environment as a contributing factor in IQ, growth, and development. For example:
* Iodine supplementation during early life (a few weeks) increases IQ
* Organophosphate exposure increases autism (also why people who live near airports have higher incidence of cancer)
* Phalates and non-sticks reduce male reproductive organ size
* Music lessons in children increases IQ.
* L-arginine during childhood increases height and free growth hormone