The more doctors test it, the more they find that eating Mediterranean is the absolute best way to lose weight. Based on the cooking and eating styles of Italy, France, Greece, Spain, and other Mediterranean countries, the plan features olive oil, fruits and vegetables, nuts, legumes, fish and poultry, whole grains and, yes, wine! It's high in heart-healthy fats and, unlike other diets, doesn't forbid any food group. "It's hard to stay on extreme diets," says Harvard nutrition expert Walter Willett, MD, PhD, whose book Eat, Drink, and Be Healthy popularized the approach in the United States. "This diet has lots of variety and wonderful flavors so people stick with it."
In a 24-week long intervention study, researchers recruited 84 obese subjects with type 2 diabetes and randomly divided them into two groups. The first group of 42 received a low-glycemic diet with a 500 calorie/day deficit. The second group ate a very low carbohydrate ketogenic diet with less than 20 grams of carbohydrates per day without calorie restriction.