[janm]

Genetics plays a part. Diabetes in Asians is a different disease; the excess fat in Asian men is stored in the muscles rather than around the belly. 150 generations of eating rice will change things. By comparison, food like potato (now a stable) have only been around in northern Europe for 6-8 generations.

For example: http://itc.conversationsnetwork.org/shows/detail4528.html