Americans whose dietary patterns include fresh, whole foods like fruits and vegetables, whole grains, legumes, lean meats, and fish have a lower incidence of major chronic disease and especially of diet-related diseases.
Unfortunately, the standard American diet (S.A.D.) is heavy in saturated fats, partially-hydrogenated oils, refined carbohydrates, and highly processed foods.
This diet, in combination with a sedentary lifestyle, large portion sizes, and high stress, is blamed for the increase in obesity and associated diseases in the U.S. (according to the Center for Disease Control, over a third of the U.S. adult population is obese). Diseases associated with obesity include type 2 diabetes, high blood pressure, coronary heart disease, stroke, gallbladder disease, osteoarthritis, sleep apnea, respiratory problems, and certain cancers, including breast cancer in women.