As an investigative journalist working in science and health, Ive spent the last decade assessing the conventional wisdom on diet, weight control and disease. My conclusion is that much of what weve been taught since the early 1970s most of which weve all come to accept is simply wrong. This might explain why those same years have seen unprecedented increases in obesity and diabetes worldwide. When I started my research, I had no idea that I would come to such contrarian views. But now I think that certain conclusions are virtually inescapable:
Obesity and being overweight are not caused by eating too much and certainly not by eating food with too much fat.
Carbohydrates, not fat, are the cause of excess weight, just as our grandparents generation always knew. Eating carbohydrates triggers a hormonal response  insulin secretion that signals our bodies to accumulate fat. This is why the fewer carbohydrates we consume, the leaner we will be. Sugar, flour and other refined carbohydrates produce an exaggerated version of this response, and so are particularly fattening.
Exercise doesnt make us lose weight, it just makes us hungry.
Dietary fat, whether saturated or not, is not a cause of heart disease. Rather the same foods that make us fat easily-digestible carbohydrates and sugars will eventually cause the diseases that are likely to kill us: heart disease, diabetes and even most cancers. As the late Tim Russerts physician explained in The New York Times shortly after Russerts death, if theres one number thats a predictor of mortality, its waist circumference. Because carbohydrate-rich foods increase our waist circumference, then it must be these same foods that shorten our lives.