The Zone Diet Explained

The Zone Diet is a nutritional plan created in 1995 by a biochemist named Dr. Barry Sears. Sears claims that America's rising obesity problem stems from hormonal imbalance--that after eating too many sugars and refined carbohydrates, people develop insulin resistance that causes the body to store fat. The "Zone" is what Sears calls the ideal hormonal balance, where energy, performance and mental clarity are at their highest. To "enter the Zone," Sears prescribes that the diet should contain 40-percent carbohydrates, 30-percent fats and 30-percent proteins.

Dietary Rules

Dieters should eat within an hour of waking up, and eat at least once every five hours. In Sears' plan, this means three meals and two snacks per day. Dieters should also drink eight or more cups of water a day and exercise as often as possible. Sears states that following the 40:30:30 ratio and eating Zone-approved foods will lead to more weight loss than adhering to a diet based on will power and calorie limitation.

Food in the Zone

The Zone Diet utilizes the glycemic index, which is a measure of the effect various foods have on blood glucose levels. Foods with a high glycemic index--most breads, rice, sweets, fruits and potatoes--are strictly limited. Foods with a low glycemic index--egg whites, lean poultry, nuts, seafood, vegetables and low-fat dairy products--are encouraged.

Meal Planning

Meals in the Zone plan should be around or under 500 calories; snacks should be around or under 100 calories. Both should include a portion or "block" of protein and carbohydrate. In a sample Zone menu, breakfast would include a large portion of egg whites and a small portion of oatmeal and strawberries. Lunch would be a salad with chicken breast, tomato and a small amount of olive oil dressing.

Pros and Cons

Unlike many other fad diets of the 1990s, the Zone Diet does not prohibit carbohydrates, and has thus been touted as a more sustainable, moderate lifestyle plan. However, the plan does limit carbohydrates, and any reduction in carbohydrates is likely to lower the dieter's energy level. Additionally, the Zone Diet is much higher in protein than the average American meal plan, and dieters must always eat protein and carbohydrates in ratio-prescribed "blocks." Consequently, eating in restaurants is difficult for dieters.

Popularity

Dr. Sears' first book, "Enter the Zone," has sold more than 4 million copies, and he has since published 10 books on his diet plan. A man named Manuel Uribe, who weighed in excess of 1,200 pounds at his heaviest, used the Zone Diet to lose more than 400 pounds as of April 2008. Celebrities such as Tiger Woods, Cindy Crawford and Jennifer Aniston reportedly have followed the Zone diet.

References

• The Zone Diet---An Overview of the Weight Loss Program
• Barry Sears' Zone Diet: The Zone Diet
• Nutrition Fact Sheet: The Zone Diet, Nutrition, Feinberg School of Medicine