When cardiologist Arthur Agatston began researching why patients have such a hard time sticking to a low-fat, calorie-restricted diet, he had no idea he would create one of the most popular diet plans of the 21st century. Originally proposed to reduce the risk of heart disease, the resulting South Beach Diet quickly gained popularity in the mid-2000s. Magazines and books spread the word of the diet's success, and the diet was quickly marked as an effective means to lose weight. Yet, the rapid success soon spun-off mimics and critics, who have blurred the lines on what actually constitutes the South Beach Diet.
Trained in cardiology, Arthur Agatston accepted the prevailing theory that low-fat diets reduce cholesterol, which would then prevent heart disease (Although most studies show very little correlation between total cholesterol and the prevalence of heart disease, the high cholesterol = heart disease myth still persists today). Surprisingly for him, Agatston found that most patients have a hard time sticking to low-fat diets while restricting calorie consumption. To explain this phenomenon, he began researching the science behind insulin resistance. He discovered that excess sugars could disrupt hormonal balances, leading to cycles of hunger and gain gain. From his research, Agatston postulated that his patients on low-fat diets consumed additional sugars, which led to increased hunger.
Knowing the damaging effects of sugar, but still fearful of the saturated fats in low-carb diets, Agatston developed a new diet to accommodate his beliefs. The South Beach Diet simply replaces so-called “bad carbs” with “good carbs” and “bad fats” with “good fats.” According to Agatston, good carbs have a low glycemic index and include vegetables, beans, and whole grains. Good fats are rich in unsaturated fats and omega-3 fatty acids and include lean meats, nuts, and fish. The diet is broken up into several phases. The first phase eliminates all sugars, processed carbs, fruits, and red meats. As the dieter progresses through the stages, the diet re-introduces most fruits and whole grains.
Since the diet avoids simple carbohydrates like processed sugars, many sources confuse the South Beach Diet with low-carb diets, such as the Atkins Diet. However, the South Beach Diet permits fiber-rich carbohydrates foods like brown rice and whole grain bread while avoiding high-fat foods like beef, pork, and dark poultry meat. Agatston tried to emphasize making “healthy” food choices, rather than choosing either low-fat or low-carb meals.
Studies on the South Beach Diet in 2004 and 2005 showed favorable results for practitioners, but the diet still has its critics. In 2006, the Journal of General Internal Medicine reviewed the major nutrition and health claims of the diet and found that only one-third of all the claims could be confirmed by scientific research. In addition, several prominent diabetes researchers have questioned the validity of the glycemic index on weight maintenance, upon which the diet is based. Others warn that the first phase of the diet could be too extreme of an adjustment for most dieters. Despite the criticism, the South Beach Diet has yielded a faithful following who actively confirm the diet's success.