Quote from wally_:
So you think that obesity is genetic? How do you then explain that so many Americans are obese, definitely more compared to Europeans and Asians. They have the same genes, mostly of European and Asian origin. Have you ever travelled overseas? If you have you must have noticed the difference. It's staggering. This country has the most obese people in the developed world despite being at the same time the most genetically diverse.
Take, for instance, Asians born in this country and those born overseas. Asians tend to be skinny, in this country they are more likely to be obese than their cousins born and living in Asia.
A friend of mine after moving to Canada lost 50 pounds within a year.
Well, I guess I know the answer: it's food (usually fast food) and lifestyle. Both of these things can be modified. Of course, I am not saying that genes did not play any role in the case of his adopted children, this could be so, but it is more likely food and lifestyle that did.