SHEDDING FAT AND STAYING FIT: CARBOHYDRATES AND TIME-RELEASED ENERGY
The less refined the carbohydrate, the more gradually its energy is released. Gradual release keeps blood sugar levels relatively stable and prevents the sharp fluctuations that lead to elevated insulin levels and aggravate problems with blood sugar regulation. Since insulin promotes fat storage, elevated levels of it may in turn promote greater fat storage. Higher insulin levels may also promote sodium retention and an increase in blood pressure. (You can see how closely interrelated the body's functions are - and why no one dietary element, like salt for high blood pressure or cholesterol for atherosclerosis, is solely responsible for disease.)
When Western-style diets are adopted by such groups as Australian aborigines or Pima Indians - who had previously depended on natural high-carbohydrate, low-fat diets - these populations develop the same diseases that we get, such as obesity, diabetes, hypertension, and gallstones. Typical Western diets have a demonstrably negative effect on health! Obesity and blood sugar abnormalities, including diabetes, were virtually unknown among the Australian aborigines and Pima Indians before they adopted Western-style foods, but they are now common. This is true also of populations in Micronesia.
Indeed, populations throughout the world whose foods are high in unrefined carbohydrates and low in fats show a near absence of the degenerative disease patterns now linked to the typical Western diet. But when people from these populations move to areas where people eat as Americans do today, they may develop a host of chronic disorders from which they were previously protected by a natural-food diet.