A cup of coffee plus exercise may reduce cancer

It seems to be that every time someone comes up with a new diet, invents a new diet pill, or finds a common ingredient that does miracles, "moderate exercise" is always encouraged. In other words, they market the diet, diet pills, or coffee in this case, to take with exercise. Well of course your going to see results! Your exercising!! I don't understand why people don't stop looking for the miracle pill and just eat right and exercise...