The longest lived people in the world are Okanowan women...who, among other things, consume a great deal of greasy pork and lard. The shortest lived people in the world are vegetarians in India.
I have seen MANY cases of heart disease and diabetes clear up on Atkins-like diets (though I am not specifically a fan of Atkins). To quote William Castelli--architect of the Framingham Heart Study: "In Framingham Massachusettes, the more saturated fat one ate, the more cholesterol one ate, the more calories one ate, the lower people's serum cholesterol. We found that the people who ate the most cholesterol, ate the most saturated fat, ate the most calories weighed the least and were the most physically active".