The Zone diet is a diet popularized in books by biochemist Barry Sears. It advocates consuming calories from carbohydrates, protein and fat in a ratio of 40%/30%/30%.
Theory
The diet centers on a "40:30:30" ratio of calories obtained daily from carbohydrates, proteins, and fats, respectively. The ideal formula has been under debate, although studies over the past several years (including a non-scientific study by the PBS documentary show Scientific American Frontiers) have shown that it can produce weight loss at reasonable rates. The Scientific American Frontiers study compared the effectiveness of several popular 'diet' regimes including the Zone; somewhat to the surprise of the show's staff, the participants on the Zone experienced the greatest fat loss while simultaneously gaining muscle mass. Participants also reported the Zone as the easiest regime to adjust to, i.e. having the fewest adverse affects such as fatigue or hunger. Most people who report fatigue find that the fatigue diminishes by day 2 or 3.
"The Zone" is Sears' term for proper hormone balance. When insulin levels are neither too high nor too low, and glucagon levels are not too high, then specific anti-inflammatory chemicals (types of eicosanoids) are released, which have similar effects to aspirin, but without downsides such as gastric bleeding. Sears claims that a 30:40 ratio of protein to carbohydrates triggers this effect, and this is called 'The Zone.' Sears claims that these natural anti-inflammatories are heart and health friendly.
Additionally, the human body in caloric balance is more efficient and does not have to store excess calories as fat. The human body cannot store fat and burn fat at the same time, and Sears believes it takes time (significant time if insulin levels were high because of unbalanced eating) to switch from the former to the latter.[citation needed] Using stored fat for energy causes weight loss.
Another key feature of the Zone diet, introduced in his later books, is an intake of a particular ratio of Omega-3 to Omega-6 fatty acids. Dr. Sears is believed to have popularized the taking of pharmaceutical grade Omega 3 fish oils.[2]
Hormonal paradoxes
Sears emphasizes a hormonal paradox contrary to the "low-fat" rationale, namely that low-fat diets increase the production of the hormone insulin, causing the body to store more fat. The example proposed by him is the cattle ranching practice of fattening livestock efficiently by feeding them lots of low-fat grain. He and others also point out the supposed irony that human diets in the West for the last twenty years have been full of low-fat carbohydrates, yet people are considered more obese now.
Additionally, Sears suggests fat consumption as essential for "burning" fat.
His rationale is: Monounsaturated fats in a meal contribute to a feeling of fullness and decreases the rate at which carbohydrates are absorbed into the bloodstream. Slower carbohydrate absorption means lower insulin levels which means less stored fat and a faster transition to fat burning. If the body needs energy and can't burn fat because of high insulin levels, a person feels tired as their brain starves and metabolism slows to compensate. This occurs because the brain runs on glucose and high insulin levels deplete blood glucose levels. Such condition, rebound hypoglycemia causes sweet cravings (which just starts the high-insulin cycle all over again).
Sears describes a Zone meal as follows: "Eat as much protein as the palm of your hand, as much nonstarchy raw vegetables as you can stand for the vitamins, enough carbohydrates to maintain mental clarity because the brain runs on glucose, and enough monounsaturated oils to keep feelings of hunger away."
[edit] Comparison to low-carb diets
The Zone is considered a low-carb diet.[3] It is not as restrictive in total carbohydrate intake as some of the other low-carbohydrate diets (e.g. the Atkins diet) that became extremely popular throughout the United States in 2003 and 2004. Sears claims these other diets miss the point. According to him, they ignore the importance of hormonal balance, as well as the influence of dietary balance on digestion and hormone production.
[edit] Specific cases
[edit] Italy
The introduction of the Zone in Italy began in 1997 by a physician, Aronne Romano M.D. who applied this nutritional style to patients and athletes. Since the 2nd edition of the book "Come Raggiungere la Zona" (The Zone), in 1999, the Chef Memo Romano and his brother Aronne modified the original recipes and menu to suit the local food and habits.
Famous obesity case
Possibly the most famous case of someone using the diet effectively has been Manuel Uribe. After weighing in at around 560 kg (1234 lbs or over 88 stone) but within 2 years had lost about 260 kg.[4].
After decades of failed weight loss methods, including a botched liposuction that nearly killed him, devotion to the Zone Diet has been the only weight loss program to have such a positive impact on the man, whose weight once topped 1,200 lbs. Dr. Barry Sears, along with two of Mexico's most prestigious physicians, Dr. Silvia Orozco Avina and Dr. Gustavo Orozco Avina, are at the helm of the interdisciplinary team of doctors, nutritionists and exercise physiologists who continue to work diligently to help Manuel reach his goal . . . and his birthday.
Manuel's current diet consists of about 2,000 calories per day broken up into six meals. His specially designed menu includes a wide variety of meals including egg-white omelets, fresh salads, chicken fajitas and fish filet in a bed of spring greens. In fact, Manuel's biggest problem is not lack of appetite control, but eating all the food he is supposed to eat.[citation needed]
Despite his weight, Dr. Sears considers Manuel one of the healthiest men in Mexico. He is not at risk for diabetes, and his blood pressure and triglyceride levels are normal. In addition, his resting heart rate averages 62 beats per minute, a level usually found in trained athletes. Even though Manuel is confined to his bed, his medical team designed a tailored exercise regimen that includes sit-ups, pull-ups and hand-biking to help build muscle mass and accelerate fat loss.[citation needed]
Famous Followers
Several Hollywood stars, including Jennifer Aniston, Renee Zellweger, Cindy Crawford, Charlie Sheen, Tiger Woods and Tom Cruise are believed to have followed the Zone diet.
Criticism
The American Heart Association does not recommend the Zone Diet due to high protein, lack of essential nutrients, and little information on long-term effects.[5] However, Sears believes the characterization of the Zone diet as 'high-protein' is inaccurate. In his book, he advocates a formula based on lean body mass and activity level to determine the appropriate daily intake of protein. For example, a female of average height and average build who has a moderately active lifestyle is encouraged to eat around 60g of protein daily.
Most Vegetarian or vegan diets, according to Sears, are highly dissimilar from The Zone because they generally utilize very little protein relative to carbohydrate consumption. This, says Sears, prohibits the body from operating truly efficiently. As critical as Sears is of vegetarian and vegan diets, individuals who promote a vegetarian diet are also very critical of aspects of the Zone and similar diets. In 2000 Dr. Sears published the Soy Zone where he outlined a zone diet based around soy protein, making it more vegetarian friendly.
Other nutritional experts, including some of Sears' former colleagues, are critical of his conclusions from the scientific evidence, contending that he has distorted or exaggerated the meaning of much of the basic research. They point out that no direct studies to verify his conclusions have been performed.[6]
Some people are simply genetically predisposed to weight gain or to develop chronic disease at an earlier age. You can’t change your genes, but in the Zone you can change the expression of your genes. That’s a powerful statement, and the way to do so is through your diet.
Diet is not a dirty word. It comes form the Greek root meaning “way of life”. This is what the Zone Diet is. It’s a way of life to help control gene expression to give you the longer and better life we all aspire to.
Don’t despair because silent inflammation can be significantly reduced in less than 30 days by following the Zone Wellness Pyramid.
What is Zone Living™?
It’s a whole new way of thinking about food and lifestyle.
Zone Living is simply how well you are able to control the expression of your genes that are involved in inflammation and the hormones generated by the diet. Using the clinically validated Zone Diet as the foundation of a total lifestyle approach; Zone Living is designed to help your body achieve the hormonal and genetic balance you need for long-term weight control, as well as optimal heart, brain and immune function. In other words, Zone Living is about controlling your future.
Wellness can be maintained for lifetime, but it all starts with your diet. All you have to do is to follow the Zone Wellness Pyramid.
Zone Diet/Eating – Eat with Balance
The Zone Diet is about balancing your hormones within a specific range to control hunger on fewer calories while still getting the proper nutrients your body needs for long-term health.
The Zone Diet balances three macronutrients – protein, carbohydrates and fat at every meal and snack.
Any diet that uses the word high or low to describe it is hormonally unsustainable. The only diet that can maintain hormonal balance for a lifetime must use the word moderate to describe it. That’s what the Zone Diet is. It’s moderate in:
• Low-fat protein
• Low glycemic-load carbs (mostly fruits and vegetables)
• Heart-healthy monounsaturated fats
Omega-3 – EPA/DHA Concentrates
Incredible Anti-inflammatory Fats for Wellness.
Reducing silent inflammation requires a constant intake of anti-inflammatory omega-3 fatty acids such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) to maximize the wellness benefits of the Zone Diet.
• EPA/DHA concentrates are the most rapid way to begin to reduce silent inflammation.
• In combination with the Zone Diet, the daily intake of adequate levels of EPA and DHA is the single most important thing you can do to support optimal heart, brain, joint, and immune function.
Polyphenols – The Anti-inflammatory Power of Fruits and Vegetables
Polyphenols are the phytochemicals that not only give fruits and vegetables their color, but also provide powerful health benefits resulting from their anti-inflammatory and anti-oxidative actions. In addition, polyphenols also activate the key enzyme (AMP kinase) that helps restore cellular ATP levels. This is why fruits and vegetables are the cornerstone of the Zone Diet.
• Reduce the expression of genes associated with inflammation
• Supply the powerful anti-oxidants needed to protect EPA and DHA.
Fitness – Moderate Exercise, 30 minutes a day, six days a week
While any type of exercise will cause some inflammation, the appropriate amount of exercise-coupled with the Zone Diet and high-dose fish oil-can induce an exceptionally popwerful anti-inflammatory response that not only repairs the damage to your muscle tissue, but also makes the muscle stronger in the process. Exercise can help ward off aging by reducing silent inflammation. It does this by alleviating insulin resistance, which in turn helps reduce visceral fat, the dangerous kind that collects on vital organs in your abdomen.
Targeted Supplements – Condition Specific
Supplements are exactly that: They supplement the Zone Wellness Pyramid. It is only by following the dietary principles of the Zone Wellness Pyramid that even the best supplpement will provide any consistent benefits. The same is true of prescription drugs, exercise, and stress reduction. Without the foundation of the Zone Wellness Pyramid you will never obtain their full benefits.
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