Diet Deception: The Zone Diet

The Premise: 

A high protein, low carbohydrate diet which limits your caloric intake and follows the ratio of 40/30/30 for carbohydrates, protein, and fat respectively. Created by Barry Sears, author of Enter the Zone, this diet makes ‘zonies’ experience rapid weight loss mostly attributed to three factors: 

1. Protein has a higher satiating effect than carbohydrates, so you feel less hungry in a high protein diet.
2. High protein suppresses the following day’s protein intake more than carbohydrates.
3. Digesting protein requires more energy than digesting carbs which increases your caloric expenditure.

High protein diets are simply those that require the person to have an intake of more than 30 percent in protein. The diet relies on the fact that insulin secretion is stimulated by carbohydrate consumption. Low carbs keep insulin in a range that allows the body to burn excess fat.

The Provisions:

Lean meats like chicken, turkey, lean steaks and just sidings of vegetables and fruits.

The Promise: 

Rapid weight loss, improved athletic performance (this is a new one!) and a lower risk of developing heart disease and cancer.

The Proof:

Randy, 30, a computer programmer said “I tried it and I lost 15 pounds, but had serious problems with my skin and bowel movement so I went off it. Regarding athletic performance, I swim a lot but I don’t think it really improved it.”

The Prognosis:

Rapid weight loss is inevitable in a low carbohydrate, high protein diet. While it contends that excessive complex carbohydrates causes obesity by increasing insulin output and fat storage, you’ll find that none of the references quoted in the book to back up these claims have ever been published.

The author vehemently advises against a vegetarian diet, completely ignoring that fact that vegetarians are far less likely to develop heart disease and cancer and are leaner than meat-eaters. Clinical studies alone in the last half century clearly show how a high protein, high fat diet can lead to higher risks for heart disease, stroke, adult onset diabetes, several types of cancer and stroke.

With regards to the 40/30/30 ratio, studies show that the average diet in most Western countries, is already an approximation of this ratio. The U.S. in particular has 60 percent of its population falling under the obese category, not to mention a steady increase over the last couple of years of incidence of heart disease and cancer. These fatal numbers are but a reflection of the same diet ratio the book encourages everyone to follow.

Like most low carb diets, the weight loss is mainly attributed to dehydration. By limiting carbohydrates (where 3 grams of water are stored in every gram of carbohydrate), zonies think that they’re actually losing a pound of fat a day. It’s also below the healthy recommended caloric intake for adults (2,200 to 2,500 calories a day) at only 1,700 calories. This causes unhealthy depletion of body mass with minimal fat loss. The weight loss is quickly regained once the body can no longer sustain the diet.

As for improvement in athletic performance, athletes would be well advised to stay away from the Zone. The recommendations for both carbohydrates and caloric intakes are insufficient to meet the energy requirements of everyday training.

The Pros’ Position:

“There are a lot of false statements made in the book. The fact that carbohydrates cause heart disease and cancer has no basis at all. Furthermore, there are so many health problems proven to be directly linked to the consumption of high levels of protein- heart conditions, stroke, cancer and even calcium loss and osteoporosis. The short term benefit of rapid weight loss isn’t worth the inevitable long term health risks.” says Ana Cruz, an L.A. nutritionist and dietician who once worked for the Duke University Medical Center.

Dr. Sanirose Orbeta, a nutrinionist adds, “Like the other new diets in the market, the nutrient ratio in The Zone diet doesn’t follow the healthy eating index, which should have 55 to 60 percent carbohydrates, 15 to 20 percent protein and 20 to 25 percent fat.”