It's not a question of eating a lot. Gorging on pasta when pregnant will just produce a type I diabetic child. The issue is animal/fish fat consumption. Women and children need quite a bit of it.
When mom eats french fries and rice the insulin spikes permanently screw up the kid's endocrine system, leaving a propensity to obesity if not diabetes.
Do you mean Type I or Type II? Everything I've read indicates that the cause of type one isn't clearly understood, but is likely an autoimmune condition. However, conditions that lead to obesity later in life can lead to type II diabetes.
Are the obesity rates in countries with diets high in rice consumption (e.g. Japan) especially high? Or is it usually offset by something (so in Japan's case: fish consumption)?
Living in Tokyo, an obese person really sticks out. You just almost never see them. You do see some fat teenagers though, since they are abandoning the traditional diet.
Japan is in love with fat in all its forms (fatty marbled beef, fatty tuna, fatty pork) and there is almost no culture of sun-screen usage, but they also are much better at producing melanin than europeans, making for pretty effective natural protection.
They also have one of (if not the) largest populations of centenarians on earth.
