If it's not penicillin, it's disinfectants. Yay.

[agoodwinsmith]

Postnatal Exposure to Household Disinfectants [linked to obesity]:
http://www.cmaj.ca/content/190/37/E1097

They mention "triclosan" specifically.

They also mention increased environmental microbes for daycare children prior to kindergarten - which shows a lower incidence of overweight in such children.