The Zone is not some mystical place. It is a state of hormonal balance that can be achieved by your diet. In particular, it can be defined as keeping the hormone insulin in a tight zone: not too high, not too low. The Zone Diet is not a diet, but a life-long hormonal control strategy.

Every time you eat, you trigger a powerful biochemical cascade that can maximize or limit your performance. Contrary to current sports nutrition dogma, high carbohydrate diets generally reduce or impair performance. By understanding the reaction of major hormones to the food you eat will help you to understand how to control your entrance into the Zone.

A high carbohydrate diet results in a rapid increase in blood glucose which causes the body to respond by increasing insulin. The role of insulin is to store this glucose preferably in muscle. If there’s too much, the glucose will be stored as body fat. This rapid rise in insulin also locks previously stored body fat in the fat cells by inhibiting the enzymes responsible for it’s release.

The insulin then causes a dramatic drop in blood sugar, making less available for the brain. So what does the average person mistakenly do when they get those low energy, hypoglycemic blues? They reach for a sports drink or "energy" bar, both loaded with carbs, raising their insulin levels even further. The results can be devastating.

The results of eating in the Zone are immediate and long term. The primary benefit is the maintenance of blood sugar levels and therefore controlling appetite. Other benefits include increased mental alertness, decreased muscular fatigue, and overall decreased body fat.

Worried about pills, potions, or lotions? Don't, there are none. This is about eating good food in prescribed portions. Worried about being hungry? You won't be. The food works with your body, not against it. Worried that this is another fad diet? Too much protein? Too much fat? No, no, and no. It is not.

Insulin is a hormone released by your pancreas following carbohydrate ingestion and the associated rise in blood sugar (glucose). Insulin triggers three important events: 1) it brings some blood sugar into the muscles where it’s used for energy, 2) it converts some blood sugar to glycogen (the stored form of sugar), and 3) insulin not only stores some blood sugar as fat, but it prevents existing fat from becoming out of storage for use as energy.

High levels of insulin compels your body to burn more carbohydrates as fuel, less fat for fuel, and helps maintain fat storage. In order to use more fats for energy, the insulin levels must be minimized. High carbohydrate diets, especially refined carbohydrates, will result in more insulin being released and the continual inhibition of fat utilization. This vicious cycle keeps your body using sugar rather than fat as the predominant fuel.

Another symptom high insulin levels may cause is excess hunger. By sending blood sugar into the muscles and fat deposits, low blood sugar, or hypoglycemia, results. This triggers hunger, often only a couple of hours (or less) after your meal. Cravings are usually for sweets.

If you want to utilize more fats, the best advice is to minimize the insulin response by limiting your intake of refined sugars and carbohydrates, which includes all sweets, non-100% whole grain breads, cereals and pasta, keeping all your carbohydrate intake to about 40% of the diet. Even certain natural foods, such as dried fruit, potatoes, honey and fruit juices are very high in carbohydrates. Keeping carbohydrates to 40% will help keep your blood sugar more stable, give you more energy and less cravings, More importantly, you will lose body fat.

Insulin responses can vary greatly from person to person. But generally, refined carbohydrates evoke a stronger and/or more rapid insulin reaction since they are higher in sugar and because the are void of their natural fiber. Psyllium and other natural fiber, when consumed with carbohydrates, can reduce the extreme blood sugar and insulin reaction often associated with carbohydrate intake.

When you eat high-carbohydrate foods, the body digests them and converts them into glucose which enters the bloodstream to be burned as energy. When small amounts of carbohydrates are eaten in a meal, a small amount of glucose enters the bloodstream and is immediately used for energy.

The problems begin when you eat a meal that is too high in carbohydrate (for example, a bagel and juice, a plate of pasta, or a sugary brownie). This is because too much glucose enters the bloodstream too rapidly. A high-carbohydrate meal stimulates a biochemical response that forces your body to burn glucose rather than stored body fat as its main source of fuel.

When you eat carbohydrates, the best advice is to eat carbohydrates that are high in fiber, low in starch, and low in sugar. Some of the best carbohydrate sources include:

One of the most important macro nutrients is protein. Protein is referred to as the "building blocks of life" because the body uses protein to rebuild and repair itself. More than half of your dry body weight consists of protein. This includes muscle, hair, skin, nails, blood, hormones, enzymes, and much more.

Adequate quality protein is the most critical component of the Zone diet. Based on your lean muscle mass, you require a specific amount of protein each day. Sources of the best high-quality protein foods include:

• Cottage cheese (low fat)
• Eggs and egg whites
• Fish
• Lean meats
• Low-fat tofu and tempeh
• Skinless turkey and chicken
• Whey protein powder

Eating enough dietary fats is also an important consideration for anyone wanting to burn more fat and spare sugar. The only real "bad" fats in the diet are the artificial ones, like margarine and other hydrogenated fats, and fried or over-heated fats. All natural fats are good for your body as long as you consume them in moderation and you have healthy metabolism.

In addition, dietary fats are one of the best ways to stimulate your metabolism, which is what you want to do if you goal is to increase fat burning. A fast metabolism converts fat to energy quicker.

A diet of 40% carbohydrate and 30% fat, leaving 30% for protein, is an excellent balance for many people who seek not only good health, but quality modification since individual needs may vary.

The phenomenon of excess carbohydrates preventing fats from being used for energy is especially true before an exercise and especially competition. For example, taking a high carbohydrate food or drink before your workout or race can have devastating effects.

Some of the best sources of "good" fats that are naturally occurring and unprocessed are:

• Avocados
• Cold Water fish (Salmon, mackerel)
• Raw nuts, nut butters, and seeds
• Safflower-based mayonnaise
• Vegetables oils (olive oil, safflower, sesame, sunflower)

The critics of the Zone continually use the tired argument that this dietary program is a high-protein diet, thereby trying to lump it in with the dangerous ketogenic diets of the 1970s. The Zone diet is a protein-adequate diet that contains more carbohydrates than protein and thus making it metabolically impossible to become ketogenic.

The diet advocates taking the exact protein that a person requires to maintain lean body mass. Furthermore, this total amount of protein should be spread evenly throughout the day so that the actual amount of protein consumed at any one meal is very small (usually 3 oz. of lean protein for females and 4 oz. of lean protein for males).