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How to Lose Weight on a Low-Carb or Glycemic-Index Diet

        Health | Weight Loss

Enter the Zone Diet
©2006 Publications International, Ltd. At dinner, Enter the Zone dieters must eat the same number of each type of block from earlier meals.

Enter the Zone advocates eating more protein and large amounts of low-glycemic index vegetables to lose weight.

Enter the Zone: The Premise

The Zone is basically a high-protein diet plan for better health, with weight loss as an added bonus. Dr. Barry Sears (a Ph.D., not an M.D.), founder of the Zone, advocates eating more protein and large amounts of low glycemic-index vegetables (those that do not raise blood sugar levels too much) to lose weight and stay healthy. In that way, his diet is much like Dr. Atkins' plan. Sears believes that it's too many carbohydrates, especially high glycemic-index carbs, that cause you to put on pounds, not extra calories.

Still, his rendition of the high-protein diet allows for considerably more carbohydrate than the Atkins diet, and he has devised his own dietary proportions, which he refers to as the "golden ratio": 40 percent carbohydrate, 30 percent protein, and 30 percent fat (40/30/30). Sears insists that his diet is better at alleviating hunger and generating mental and physical energy. He claims that the diet not only burns fat, but it helps fight heart disease, diabetes, PMS, chronic fatigue, depression, and cancer, and that it helps alleviate the symptoms of multiple sclerosis and AIDS.

The Rationale

By adhering to his dietary formula -- what he calls "entering the Zone" -- Sears promises dieters a reduced risk of several diseases as well as easy weight loss. Like some other weight-loss diets, which have very little in common with the Zone, Sears' plan is supposed to do this by controlling and bringing into balance the body's hormones, particularly insulin. Sears goes so far as to say, "Food is the most powerful drug you will ever encounter. Learning how to control hormonal responses to food is your passport to entering and staying in the Zone." Though Sears has little good to say about most carbohydrates (they take you out of the Zone and are stored as excess fat), the diet allows for 40 percent of calories from high-fiber, carbohydrate-rich foods such as broccoli, cauliflower, kiwi, cherries, chickpeas, and black beans.

What's for Breakfast, Lunch, and Dinner?

Sears insists that the 40/30/30 ratio is the secret to good health and must be adhered to at every meal and snack, not just over the course of the day. The diet recommends that you eat five times a day and that you always eat a Zone meal or snack within one hour of waking. Food is dished up in "blocks," which are divided up into protein, fat, and carbohydrate. A meal could consist of 2 to 4 blocks of protein, carbohydrate, and fat, but it must be consistent.

In other words, if you have 2 blocks of protein, 2 blocks of carbohydrate, and 2 blocks of fat at breakfast, you must eat the same number of each type of block at lunch and dinner, too. The diet generally ends up providing about 800 to 1,200 calories a day. The guidelines about the number of blocks each of us needs are fairly strict, and the book guides readers in determining protein needs based on body size, age, and activity level. Once you know what your protein needs are, you'll also be able to set limits for the amount of fat and carbohydrate you can eat.

But it's difficult to plan and follow the ratio, making sure to choose the right food and stick to the prescribed number and proportion of food blocks at each meal. Because the carbohydrate foods allowed generally provide so few calories per serving, the dieter is required to consume large quantities from the "favorable carbohydrates" list. To avoid hunger and maintain your energy, you should never let more than five hours pass without eating a Zone-favorable meal or snack. Several packaged Zone-friendly foods, such as snack bars, microwavable meals, and drinks, as well as Zone-friendly supplements, are available for purchase online at (By joining the ZonePerfect Club, you get discounts on the Zone products.)

The diet's official Web site,, offers an online health profile assessment, customized meals, interactive tools, shopping lists, online nutritionists, and other extras not found in the book. You'll pay $52 for every 3 months of membership.

Fact or Fiction: What the Experts Say

Chris Rosenbloom, Ph.D., R.D., associate professor of nutrition at Georgia State University, has analyzed and even followed the diet herself and says it's hard to plan and stick with Sears' recommendations. And all his talk about "carbohydrate hell" -- the physical problems that eating too many high glycemic-index foods cause -- has little basis in fact. The diet may work for some people, but it's no magic formula for weight loss, Rosenbloom says.

Gains and Losses/What's the Damage?

Rosenbloom's analysis of the Zone found it came up short in B vitamins, magnesium, and zinc. The restrictions to only low glycemic-index foods leave some super-nutritious foods, which happen to be high glycemic, out of the plan. Moreover, the diet advises against dairy foods and wheat and therefore could come up low in calcium, vitamin D, and fiber. Ironically, though Sears promises dieters increased energy, sticking with the diet too long could end up making you feel dragged down. That's because the calorie levels can be far too low to keep you going or provide all the nutrients necessary for good health.

SugarBusters! is another glycemic-index diet. Click on the next section to learn more.

This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Consumer Guide (R), Publications International, Ltd., the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.