The Zone Diet

Every diet comes with its own rules and promises: “Do this and you'll achieve that”. Diet promises are often based on half truths, unproven information and irrelevant research studies. In the worst case they are based on your search for the “the ultimate diet”. That's the magic formula that can make you slimmer, younger, healthier, probably in this particular order. Dietary programs and scores of "magic products" which sounded so exciting at the time have proved to be nothing more than marketing strategies.

There's nothing wrong with following a weight loss diet. But before you start, you should do at least two things:

• Find out more about diet nutrition facts and human body functions
• Talk to your doctor to see if the diet is fit for your metabolism and state of health

The Six Major Nutrients
• Carbohydrates
• Proteins
• Fats
• Vitamins
• Minerals
• Water

Why Carbohydrates Are Important
Carbohydrates are the favourite, cheapest source of energy for the human body. Simple carbohydrates are easy to digest and quickly absorbed. They can be found in sugar and sweets, honey, fruits and fruit juices. The simplest carb is glucose.

Complex carbohydrates can be found naturally in starches and fibre. Starches are absorbed slowly, as they have to be broken into simple carbohydrates first. They can be found in plants, vegetables, grains. Fibre does not supply much energy to the body and usually it is not digested. It is however helpful in regulating blood sugar and in eliminating waste through the intestines. A diet low in fibre can lead to constipation and even colon cancer.

When we eat carbs, the simple ones pass directly into our blood system. Insulin secretion is stimulated. Insulin is a hormone that helps glucose reach tissues and supply energy. If there is any glucose left, insulin stores it in muscles and liver as glycogen (one glucose molecule with two molecules of water). And if, after that, there is still some glucose left, insulin stores it as fat in the fat cells. The complex carbs follow the same process after being transformed into simple carbs. Brain activity is sustained only through glucose feeding.

When we don't eat carbs, this stimulates the secretion of glucagon. Glucagon is a hormone that carries out the opposite function of insulin. First, it helps to release glucose from glycogen storage. Of course, water molecules are also released and eliminated. If we continue not to eat carbohydrates, glucagon releases fat from the fat tissues and helps to process it back to simple carbohydrates, to supply our energy needs.

The problem with carbs is that they usually come in foods with a high glycemic index. This index measures how quickly the food we eat is processed into glucose and enters the bloodstream. Overconsumption of high glycemic foods provokes rapid increase in blood sugar, and overproduction of insulin (hyperinsulinemia). Insulin tries to “work” as quickly as possible, absorbing glucose from the blood. Sugar blood level decreases rapidly. These wide fluctuations of blood sugar level have been associated with moodiness, rapid fat storage, increase of LDL cholesterol, decrease of HDL cholesterol, high blood pressure and several other problems. Together, they create “Syndrome X”.

Why Proteins Are Important
If glucose is “fuel” for the body, protein is “building material”. It builds blood, muscles, organs, skin, hair, nails. Protein is formed of 22 amino acids, eight of which the body is not able to produce, and must come from our diet. These are called essential amino acids. All amino acids must be present for the production of protein, tissue building, creating the hormones, enzymes and other functions. The excess protein we consume is converted to fat. Protein is converted to energy only when glucose and fat storage are complete.

Why Fats Are Important
Fats are a secondary, very concentrated, source of energy that our body uses. We can either eat fat, or produce it from excess glucose. The human body stores as fat all the energy it does not need for the burning processes. In fact, our body is a very “low consumption machine”. It uses as little as possible energy for burning, and stores more for rainy days. Fat dissolves and carries some of the vitamins that are not water-soluble .Like proteins, fats include some essential fatty acids that the body cannot produce and thus must be provided by food. Fatty acids can be saturated, mono unsaturated and polyunsaturated.

Fats or lipids are stored in fat cells. We are born with some of these fat cells. The rest develop at puberty. After this period, fat cells do not multiply anymore. They can enlarge and store more lipids. The fat we ingest is carried into the fat cells through a complex process. This process depends on the insulin level in the blood. Insulin activates enzymes called lipoprotein lipases which break down the fats into fatty acids.

Eating too many saturated fats is associated with high LDL cholesterol levels. LDL cholesterol is also known as “bad cholesterol” and causes blood-vessel diseases. Mono- and polyunsaturated fats provide both LDL and HDL cholesterol.

Cholesterol is a fat-like substance that belongs to the steroids group. Cholesterol insulates cells and protects them from temperature variations, to help create sex hormones, bile salts, (to help digestion), and produce vitamin D in skin tissue when exposed to the sun.

Our body is able to produce the cholesterol it needs to function properly. But we also ingest cholesterol. The discussion about “good” and “bad” doesn't refer to cholesterol itself but to the molecules that carry it.

Apoproteins are compounds that can dissolve and carry cholesterol and lipids. Apoproteins combined with lipids form lipoproteins. “Bad cholesterol” is in fact Low Density Lipoprotein and “good cholesterol” is High Density Lipoprotein. HDL is able to solve and carry lipids and cholesterol, while LDL is less able to do that. When we go to the doctor and ask for a cholesterol level test, he or she measures total cholesterol, HDL and LDL levels in the bloodstream. Two situations are considered “high heart attack risk”:

1. High total cholesterol levels in the blood, even if the HDL/LDL ratio is good;
2. High LDL levels, even though total cholesterol levels are low.

Carbohydrates, fats and proteins are nutrients with energy value. The energy value measures in calories.

Why Vitamins Are Important
Vitamins are nutrients that our body cannot produce. They have no energy value, although they help to convert fat and carbohydrates into energy. They contribute to many metabolic functions and help to develop body structures. There are two classes of vitamins:

Fat Soluble
Vitamin A (cortisol)
Lack of it leads to poor eyesight, night blindness, dry skin, and inappropriate bone development. An excess of vitamin A can be very toxic to human body. It is stored in the liver;

Vitamin D (cholecalciferol)
Precursors of vitamin D are assimilated from foods like milk and stored in the skin. In contact with ultraviolet light, these D-precursors turn into D3 vitamin, “or natural vitamin D”. This helps calcium and magnesium assimilation. Fish liver oil and butter are good sources of vitamin D;

Alpha-Tocopherol (Vitamin E)
Fulfills the functions of an enzyme. It collects free radicals that can damage membranes and cell components. Vegetable oils are a source of vitamin E.

Vitamin K (menadione)

Vitamin K helps the blood clotting process. It can be found in green vegetables, and, in small amounts, in eggs and dairy products;

Water Soluble
Vitamin C (ascorbic acid)

Vitamin C is an antioxidant. It collects free radicals and is popular as an antiviral agent, although this last function is controversial. It is commonly found in fresh vegetables and fruit (peppers, tomatoes, citrus fruits). Severe lack of vitamin C can lead to scurvy;

B complexB1 (Thiamine): Maintains normal functioning of the nervous system, muscles and heart. It helps in the growing process and can be found in flour, beans, pork, salmon, soybeans. Lack of thiamine leads to beri-beri.

B2 (Riboflavin): Also involved in the growing process, helps in the formation of red blood cells, steroids and glycogen. It also contributes to breaking down fat. Almonds, yeast, cheese, eggs, chicken and other kinds of meat are sources of riboflavin. People who lack vitamin B2 develop inflammations, insomnia, dizziness and problems with memory.


B3 (Niacin): Is found in legumes and whole grains. Lack of niacin leads to a severe disease called pellagra.

B6 (Pyridoxine):Helps with brain functions and blood cell formation. It is also involved in the metabolism of macro nutrients (protein, carbohydrate and fat. Common sources of vitamin B6 are bananas, carrots, nuts, rice, fish, soybeans.

B12 (Cyanocobalamin):Can be found in eggs and dairy products and helps normal growth.

B9 (Folic acid):Another vitamin that helps growing processes, especially fetus development during pregnancy. Brewer's yeast is a rich source.

B5 (Pantothenic acid): Biotin acts as a carbon dioxide-carrier. It produces antibodies and digestive enzymes.

Why Minerals Are Important
Minerals are substances that can not be produced by the human body. Several of them are very important to its functioning. That is why we need to ingest them. They are important for the metabolism, hormone production, bone development and other biological functions.

Why Water Is Important
Water represents most of our body composition (70% to 80%). Water is a favourable medium for cell metabolic reactions and helps to maintain a stable body temperature.

Barry Sears' Zone Diet
Dr. Barry Sears' is the creator of the famous but controversial Zone Diet. When you ”enter the zone”, he says, you also go into a physical state of hormonal balance. This leads your body to level of maximum efficiency. Many experts consider Zone just another “fad diet”. The main objection to Zone is lack of scientific support.

The Zone Diet was originally developed by Dr. Barry Sears, PhD. He worked as a researcher at the Boston University School of Medicine and the Massachusetts Institute of Technology. He has spent many years studying lipids, and their inflammatory role in the development of chronic disease.

According to some sources, Sears began working on Zone Diet in the early 1970s, shortly after his father's death of a heart attack.

Back in 1982, the Nobel Price for Medicine was granted to research that proved a relationship between the hormones called “eicosanoids” and the development of certain diseases. These included diabetes, cardiovascular diseases, diseases of the immune system and cancers. Somehow, this moment is also supposed to have turned Dr. Sears' attention from his own studies of lipids towards a related subject: the relationship between food and hormone production inside the body.

In 1995, Dr. Sears published his first book on the Zone Diet: “Enter The Zone”, The book became a number one worldwide best-seller, selling four million copies. Since then, Dr. Sears has published 10 more books on the same subject.

What Is “The Zone”?
Dr. Sears defines the zone as an ideal state of body and mind, in which we feel fresh and energized, and function to our maximum efficiency. The term is borrowed from the language of athletes. The goal of athletes is to reach their peak performance zone. This lasts a few minutes, or the time it takes to burn a match. Dr. Sears believes he can offer a way to make us “stay in the zone” as long as possible, even for a lifetime. “Enter Zone diet” became key terminology that Sears and acolytes use to encourage people believe this possibility.

Although the Zone Diet claimed to be the answer for staying in the zone, many athletes who follow this diet complained that it didn't help them improve performance levels. On the contrary, they complained of losing concentration and of worse results.

The Zone Diet History in Theory
Inspired by the 1982 Nobel moment, Dr. Sears launched his theory about dietary fat driving from eicosanoids which can lead to certain diseases. According to Dr. Sears, the key for a healthy body is a good hormone level. In order to regulate hormones like insulin, glucagon and eicosanoids, the body uses essential substances from food. As a result, food is considered by Dr. Sears the most powerful drug that our body uses every day.

So where does the problem lie? We feed our body every day, and still get become ill and fat. The problem lies in what we eat, and in what amounts. The modern individual eats "junk food" which does not fulfill the body's needs. Dr. Sears even criticized the USDA. For decades the USDA had encouraged people to eat a diet rich in carbohydrates and poor in fats and proteins. Up to this point, there is little difference from other dietary theories (e.g. Atkins and South Beach Diet. But Dr. Sears doesn't connect Zone Diet directly to vitamins, minerals and other important nutrients. He sees food as an instrument to control the blood insulin level.

According to Dr. Sears, while human DNA has not changed much over the last 100,000 years, our eating habits have. In the prehistoric era, the human being ate fruit and meat, a diet rich in proteins and fats, and poor in carbohydrates. Developing this hypothesis, Dr. Sears established the optimum ratio of carbohydrates, protein and fat which any individual has to respect in a daily menu. This is widely known as the 40-30-30 ratio.

... and in Practice

Up to now, although he has published 11 books about this subject, Dr. Sears has not yet provided any scientific proof that Zone diet works as he claims. The opinions of researchers contradict each other on this subject.

Yes, the Zone Diet is good as a diet to lose weight. Many people who followed it the diet agreed they were losing around 1.5 pounds a week. We also have the testimonies of many people who could not lose weight with other diets, but succeeded with Zone.

Zone diet works well for overweight people, but is it really a way of life? Zoners strongly believe that it is. Some food experts approve of the Zone as “a good diet”. After all, it encourages consumption of lean grilled meat, vegetables and fruit.

The Zone is also considered user-friendly, as it is easy to follow. For example, one meal should consist of one slice of lean meat (poultry or fish) the size of your own palm, and the other two-thirds of the plate should be stuffed with fruit and vegetables.

Nevertheless, some nutritionists and experts highlight at least one problem of the Zone diet. It limits the consumption of essential nutrients that our body needs to function properly. The first nominees are carbohydrates, which are transformed into glucose, the body's favourite source of energy.

Up to now, many questions about the scientific rhetoric of Zone diet still remain unanswered. This is especially true when it comes to its efficiency in preventing cardiovascular diseases, cancer or type II diabetes. But thousands of people (including many celebrities) claim it has worked for them. They say they have no intention of feeding themselves in another manner until the end of their lives.

How The Zone Diet Works
How the Zone Diet helps you lose weight, prevent diseases and lead you to a healthy life. We will also briefly mention the Zone's “good” and “bad” foods.

The Zone is considered a low-carb diet. The Atkins Diet and the South Beach Diet are also low-carb, at least in their first phase. They all criticize the recommendations of the USDA in their claims for a healthy diet. They refer to the USDA's food pyramid as a marketing tool to sell bread and pastry products.

Dr. Atkins created his own food pyramid to reflect what is, in his opinion, a healthy eating scheme.

Dr. Barry Sears, creator of Zone Diet, came up with a scheme of his own: the 40-30-30 ratio. To control our hormonal levels and preserve our health, says Dr. Sears, we need to feed our body an approximate ratios of 40% carbohydrates, 30% protein and 30% fats.

How Does the Zone Diet Helps You Lose Weight?
Our body has its natural mechanisms to keep us healthy, and maintain a normal lifestyle. The body takes its energy and vital substances from food. Feeling hungry is a sign that we need more energy and nutrients. As we eat, we reach saturation. At this point we feel satisfied for the next few hours.

But our body is a bit too efficient. It does not transfer all the energy we feed it into the burning processes, but only a small amount of it. The rest of the energy is saved for a rainy day.

The favourite source of energy for our body is glucose. Glucose is the simplest carbohydrate. It can be processed from complex carbohydrates contained in high amounts in grains, pasta, rice, bread and potatoes. Fruit contains fructose, another carbohydrate. Carbs can be found in smaller amounts in certain vegetables.

When we eat bread, for example, complex carbohydrates enter our bodies, where they are transformed into glucose. Glucose is easily transferred into the bloodstream. At this moment, insulin gets in the way. The role of insulin, a well-known hormone produced by the pancreas, is to absorb the glucose (commonly known as sugar) from the blood. The blood uses glucose for energy stores it, partially in the liver (together with two molecules of water). The remaining glucose goes into fat tissues. Fat cells do not multiply over the years. They just get bigger. This is how we put on weight.

It has been proven that you can lose weight with this diet. Let's see why it works.

Zone Diet Facts
You have probably heard or read that Zone Diet helps you lose weight by balancing your blood insulin level. How do we explain this?

Let's have a look at the recommendations:

• Cut down on those diet foods with a high glycemic index (pasta, white bread, cookies, sugar). Keep fruits and vegetables as your favourite source of carbs.
• Calculate your daily protein intake and supply it mostly from lean meat and fish.
• Eat mono saturated fats; olive oil is strongly recommended.
• Exercise.

• The recommended calorie intake should not exceed 500 kcal per meal and 100 kcal per snack. This derives from the block meals method. Three meals and two snacks per day leads us to around 1,700 calories daily. This is considered a little below the average need of energy for one day.

We see that all the actions we are supposed to take will reduce the amount of insulin produced by the pancreas and enhance the glucagon level. Glucagon is a hormone which behaves in precisely the opposite to insulin.

• Cutting high glycemic foods reduces the sugar level in our blood, so there is no further need for insulin.

• Processing proteins and mono saturated fats does not involve insulin. Dr. Sears' theory says that "dietary fat alone can't make you fat", as fat slows down the entry of carbohydrates into the bloodstream.

• Keeping a low calorie intake forces the body to supply energy from resources already stored in the body. Glucagon helps here, by breaking amino-acid chains and transforming them into simple carbs that can now be burned in tissues to release energy. It is clear that you lose weight by burning fat instead of glucose;

• The same process happens when we exercise: if your glucose level in the blood stream is already balanced, you burn energy from your fat reserves.

In conclusion, insulin is known for its role in storing fat. Lowering the insulin level, claim the "zoners", reduces fat storage. But there is still a serious question about this diet. Does it really make you lose weight by reducing insulin levels in your blood, or by cutting calories and putting you through exercise like so many regular diets do.

Zone Diet Advantage: Your long-term weight-loss solution!

How Does the Zone Diet Work in Preventing Diseases?
First, let's have a look at diseases like type II diabetes and cardiovascular diseases:

Type II Diabetes
Apart from type I diabetes, caused by a malfunction of the pancreas that is not able to produce insulin, type II diabetes often occurs to non-insulin-dependent people. For some reason, at a certain moment in their life, their body becomes unable to use its own insulin. The body becomes immune to insulin. Although there is not enough scientific data to support this, type II diabetes occurs more frequently in people over 40. It is also linked to obesity. In circumstances in which there is a high tolerance to glucose, insulin already in the blood cannot be used and sent further to the cells.

Cardiovascular Affections
Traditionally, cardiovascular diseases are linked to several causes, among them, cholesterol level in the blood. It seems the problem is "bad cholesterol" coming from dietary saturated fat. At first, it thickens the blood, causing bad circulation. Then, it deposits on the blood vessels. When it narrows or even blocks arteries, arteriosclerosis occurs. If the coronary arteries are blocked, a heart attack is imminent. If a blood vessel in the brain is blocked, it can cause a stroke.

Let's take another look at Dr. Sears' recommendations:

• Cut high-glycemic foods, saturated fats, the amount of calorie intake. All these measures reduce body fat storage, make you lose weight and put you into the "green area" of low type II diabetes risk.

• Eat only mono-saturated fats: olive oil, guacamole, almonds, macadamia nuts, borage oil. They are known to contain low levels of LDL - "bad cholesterol" and high levels of HDL - "the good one".

These conditions alone explain why Zone Diet should reduce type II diabetes and the risk of cardiovascular disease. No sources have been yet found to justify claims that it prevents cancer.

Zone Diet Basics: Principles, Calorie Limits
The principles and the rules that you have to keep in mind to “stay in the Zone”. These rules are connected to what you can eat, amounts, number of meals per day and calorie limits. Also, we'll see other conditions that help increase the effects of Zone Diet, such as physical exercise.

Remember that in athletics, “the zone”, meaning the peak performance level of the human body, is believed to last only a few minutes. Dr. Barry Sears claims that eating a 40-30-30 ratio of carbs, proteins and fats at one meal helps the body reach and stay in The Zone for approximately five hours. A Zone snack is said to keep you in the Zone for two to two-and-a-half hours. With three Zone meals and two Zone snacks every day, according to Dr. Sears' theory, someone could spend a lifetime in The Zone. That is why Zone Diet is considered not only a weight-loss diet, but also a way of life.

What Is the 40-30-30 Ratio?
The USDA food pyramid mentioned before recommends eating approximately 55% carbs, 15% protein and 30% fat at every meal. Dr. Sears believes that this eating scheme, which is based on carbohydrates (especially processed grains), is completely wrong. It has led, he thinks, to the high rates of obesity and other conditions which are typical of modern America.

Dr. Barry Sears's Zone Diet Plan, he believes, is appropriate to our DNA structure. This is the 40-30-30 plan, the key principle of the Zone Diet, which leads to maintenance of the correct level of insulin.

The Zone Diet Basics
Eat the correct ratio of 40% carbohydrate, 30% protein and 30% fat at every meal;
Eat five times a day, whether you feel hungry or not: have three Zone meals and two Zone snacks;
Don't let more than five hours pass without eating;
Eat preferably when you are not so hungry, and your brain activity and concentration level are good. When you are hungry, your insulin level is too low. You are not in the Zone any longer.
Drink eight glasses of water every day (1 glass equals 8 ounces);
Eat only low fat protein, keep fruits and vegetables as your favorite source of carbohydrates, and add a dash of mono saturated fat (e.g. olive oil) to every meal;
A Zone diet meal should not lead to a calorie intake higher than 500kcal. A Zone Diet snack should provide 100kcal.
Use pasta, bread and other grain-foods only as a “condiment” for your meals.
Exercise moderately to keep your body in a good shape.
Don't worry if you leave the diet once, Dr. Sears says. With the next 40-30-30 meal you'll get right back into the Zone.