I think you just about covered the problems with this story. We never had an "obesity" crisis; but, the govt. started pushing grains and carbs as healthier for us; and, voila!, an obesity crisis.
I knew a woman in her 70's who ate very healthy diet, where the only meat she ever ate was white meat chicken. Her doctor ended up having to put her on two different cholesterol medicines at once because her diet, and one pill wasn't handling her cholesterol problems. She was healthy, had a good weight (no fat at all on her body, really), she exercised; but, her body had a problem with cholesterol.
Statin blockers are another horror story, especially for a woman like this.