to quote my friend lori, the howling noise you hear is me yelling about an underlying third cause for type 2 diabetes. (rather less politely than she is, i must say.

Diabetes from a Plastic? Estrogen mimic provokes insulin resistance: Science News Online, Jan. 21, 2006

Exposure to small amounts of an ingredient in polycarbonate plastic may increase a person's risk of diabetes, according to a new study in mice.

The synthetic chemical called bisphenol-A is used to make dental sealants, sturdy microwavable plastics, linings for metal food-and-beverage containers, baby bottles, and numerous other products. When consumed, the chemical can mimic the effects of estrogen. Previous tests had found that bisphenol-A can leach into food and water and that it's widely prevalent in human blood.

The newfound contribution of the chemical to insulin resistance, a precursor to diabetes, might partially explain the global epidemic of that disease, says Angel Nadal of Miguel Hernández University of Elche in Spain, who led the new study.

earlier studies, for the record, have shown that exposure to bisphenol-a increases the rate of obesity in mice.