Diets are viewed with skepticism because even though they work, most people can’t restrict their food indefinitely and regain weight. However, European researchers have identified the best way to make some relatively simple changes to keep weight off.

In the largest study of its kind, published in the New England Journal of Medicine, researchers tested different diets on nearly 772 overweight families. The aim was to determine the best diet to prevent weight regain.

Adults started with a very low-calorie, strict diet for eight weeks and lost an average of nearly 25 pounds. During the next six months, they were assigned to different types of low-fat diets to prevent weight regain. Children in these families ate the same food as their parents during this six-month period but did not go on the initial weight-loss diet.

Differences in Diets

Although the diets were all low in fat, they varied in the amount of protein and the type of carbohydrates, designated as low- or high-glycemic. Once eaten, low-glycemic carbohydrates, such as whole grains and non-starchy vegetables, convert slowly to blood sugar, keeping energy levels stable and staving off hunger. But high-glycemic carbohydrates, such as refined grains (white rice, white bread) and sugary foods, convert rapidly, provoke cravings for more of the same, and encourage overeating.

A simple way of looking at the glycemic principle is this: Starchy, sugary foods that make you want to eat more are high glycemic — one donut leads to another. In contrast, it’s unlikely that anyone has ever binged on broccoli, which is low glycemic.

Study Conclusions

Adults who ate a diet high in lean protein combined with low-glycemic carbohydrates kept weight off. On this same type of diet, overweight children spontaneously lost weight. In this stage of the study, no one was asked to restrict the amount of food they ate.

Among the families on other diets, those eating the least protein and the most refined, high-glycemic carbohydrates regained the most weight.

Simple Steps

Whether you’re trying to maintain a recent weight loss or just want to prevent weight gain, the basic message from this study boils down to a few key principles:

• Don’t skimp on lean protein, including lean meat, fish and poultry, low-fat dairy products (without sugar), and beans.
• Choose carbohydrates wisely: brown rice instead of white; whole grain versions of bread, crackers, or pasta; and sugary foods only occasionally, as a treat. Don’t limit non-starchy vegetables that are raw, steamed, or grilled.
• Skip deep frying or using creamy sauces and instead, try stir-frying, using low-sodium marinades and seasoning food with a variety of herbs and spices.

To learn more about which foods are low or high glycemic, visit Glycemic Index. If you prefer to follow a specific diet based on these principles or want to try some new recipes, check out The South Beach Diet.