Westerners could be genetically programmed to consume fatty foods and alcohol more than those from the east, researchers have claimed.
Scientists at the University of Aberdeen say a genetic switch - DNA which turns genes on or off within cells - regulates appetite and thirst.
The study suggests it is also linked to depression.
Dr Alasdair MacKenzie conceded it would not stop those moving to the west adapting to its lifestyle.
Obesity levels have risen sharply in many Western countries since the 1970s.
Dr MacKenzie, who lead the study team, told BBC Scotland they found Europeans were more inclined to consume fatty foods and alcohol - but that people from the East could end up with the same problems if adapting to a new culture.
Well everything makes so much sense now. Here I am in the pub, lunchtime Friday. A few beers, some greasy chips and feeling sad. Don't really need a study to explain this one.