Zone Diet :: Basis for the Zone diet
The basis for the Zone diet, by Barry Sears, Ph.D. (a biochemist, neither a physician nor a dietitian), is that if a person eats the correct ratio of carbohydrate to protein to fat (40/30/30), s/he will improve his or her health, weight, and athletic performance, because certain hormones will be balanced and therefore in the preferred “zone.” The hormones he focuses on are insulin (necessary for glucose to enter our cells) and eicosanoids (hormone-like substances that regulate inflammation. Some eicosanoids are by-products of metabolism.).
Sears alleges that the American public is overweight due to a high intake of carbohydrates, and that this style of eating causes an over-production of insulin. In addition to causing weight gain, excess insulin leads to an imbalance in eicosanoids that he links to other aspects of ill health, such as heart disease, cancer, and arthritis, among others. The solution, Dr. Sears offers, is to eat a lower carb, higher protein, and moderate fat diet to balance these hormones within the preferred “zone.”
The positive part about the Zone diet is that it encourages its followers to eat often throughout the day – at least every five hours. It also eliminates foods many people overeat, such as sweets, chips, certain starches, and, of course, junk food. It concentrates on including a number of healthful foods – low glycemic fruits and grains, vegetables, lean proteins, and monounsaturated and omega-3 fats. (Low glycemic foods, such as cherries, grapefruit, nuts, and lentils, don’t cause blood glucose levels to increase quickly, and therefore require lower levels of insulin than higher glycemic foods, which include white potatoes, corn flakes, and dates.) The Zone diet works for its followers because it is actually a low calorie diet. For instance, the sample meal plans for an average woman totaled approximately 1200 – 1300 calories per day. Most women would lose weight at this level of caloric intake, regardless of the source(s) of these calories.