However, critics say it lets dieters eat too many carbohydrates while setting restrictions on calories from fat. They also say the changes required in eating habits may be too extreme for many people to follow. Unlike the Ornish diet, low carbohydrate diets limit foods that are high in carbohydrates. These diets advise people to avoid things like white flour, pasta, rice, potatoes and foods high in sugar. Instead they suggest that people eat foods that are high in proteins and fats.

These include foods like meat, fish, chicken, eggs, cheese and nuts. The Atkins diet is one of the most popular of these diets. It suggests that people eat fewer than 20 grams of carbohydrates a day. This amount is slowly increased to between 40 and 100 grams of carbohydrates a day to keep the weight off.

Both weight loss plans have been carefully studied over the years. But, no one plan has come out as a clear winner. In 2008, a study in the New England Journal of Medicine found low-carb diets to be the best at providing the most weight loss. The study was led by researchers at the Brigham and Women’s Hospital in Boston and Ben Gurion University in Israel.

The researchers studied more than 300 obese patients who followed one of three diet plans. These included a low-fat diet, a low-carb diet and a Mediterranean diet, which is made up of fruits, vegetables, lean proteins, olive oil and nuts. A similar study published a year later looked at more than 800 dieters.