It seems more a enviroment/culturual/city walkability thing
It seems more a enviroment/culturual/city walkability thing
Across time and between nations now the role of fat is pretty clear. More fat, thinner people. The recent studies that have put people on high fat, low carb diets are unmatched. People lose the weight and keep it off when you tell them to cut the potatoes and eat butter instead.
Regarding weight loss: I work & exercise with a variety of body types (these body types have people names too!), and, within this small sample, I've found that the dominating factor in overall weight is diet, not exercise.
Essentially, exercise controls muscle tone and how "tight" the skin is, while diet seems to control the overall body shape.
Furthermore, in the 1970's the Japanese diet was even more dominated by carbohydrates and people the populace was even thinner. At that time, 75% of calories were supplied by rice, and close to 90% by carbohydrates in general.
The phenomena isn't restricted to Japan either China is also seeing increasing obesity, heart disease and diabetes as its people living in top-tier and second tier cities adopt diets higher in fat and higher in protein.
The current American diet is actually unusually high in protein and fat by historical (i.e. pre-WWII) standards.
I can't comment on why Japanese have relatively low rates of obesity for the industrialized world with a starchy diet. But the pattern does generally hold true.
> The current American diet is actually unusually high in protein and fat by historical (i.e. pre-WWII) standards.
This is simply wrong with regard to fat. I don't know about the exact change in protein intake, but people eat much less fat and oil now than historically. You can't even get things like beef kidney, suet, or lard anymore at American grocery stores.