The Zone Diet: A Complete Overview

The Zone Diet has been popular for several decades.

It encourages followers to eat a certain amount of protein, carbs and fat at every meal in order to reduce inflammation in the body, among other health benefits.

However, critics have targeted some of its health claims.

This article provides a detailed overview of the Zone Diet, including how to follow it, its benefits and disadvantages.

Chicken Salad With Dressing

What Is the Zone Diet?

The Zone Diet instructs its followers to stick to eating a specific ratio of 40% carbs, 30% protein and 30% fat.

As part of the diet, carbs should have a low glycemic index, which means they provide a slow release of sugar into the blood to keep you fuller for longer. Protein should be lean and fat should be mostly monounsaturated.

The Zone Diet was developed more than 30 years ago by Dr. Barry Sears, an American biochemist. His best-selling book The Zone was published in 1995.

Dr. Sears developed this diet after losing family members to early deaths from heart attacks, and felt that he was at risk unless he found a way to fight it.

The Zone Diet claims to reduce the inflammation in your body. Dr. Sears proposed inflammation was the reason people gain weight, become sick and age faster.

Proponents of the diet claim that once you reduce inflammation, you will lose fat at the fastest rate possible, slow down aging, reduce your risk of chronic disease and improve your performance.

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Summary: The Zone Diet follows a specific ratio of 40% carbs, 30% protein and 30% fat. It was created by Dr. Barry Sears more than 30 years ago.

How Do You Follow the Zone Diet?

Hand Holding Half a Kiwi

The Zone Diet has no specific phases and is designed to be followed for a lifetime.

There are two ways to follow the Zone Diet: the hand-eye method, or using Zone food blocks.

Most people start with the hand-eye method and progress to using Zone food blocks later, since it is more advanced. You can switch between both methods whenever you feel like, since they each have their own benefits.

The Hand-Eye Method

The hand-eye method is the easiest way to start the Zone Diet.

As the name suggests, your hand and eye are the only tools you need to get started, although wearing a watch is also recommended to keep an eye on when to eat.

In this method, your hand takes on several uses. You use it to determine your portion sizes. Your five fingers remind you to eat five times a day and never go without food for five hours.

Meanwhile, you use your eye to estimate portions on your plate. To design a Zone-friendly plate, you need to first divide your plate into thirds.

  • One-third lean protein: One-third of your plate should have a source of lean protein, roughly the size and thickness of your palm.
  • Two-thirds carbs: Two-thirds of your plate should be filled with carbs with a low glycemic index.
  • A little fat: Add a dash of monounsaturated fat to your plate, such as olive oil, avocado or almonds.

The hand-eye method is designed to be a simple way for a beginner to follow the Zone Diet.

It is also flexible and allows you to eat out at restaurants while on the Zone Diet, by using your hand and eyes as tools to choose options that fit Zone recommendations.

You can learn more about eating out on this diet here.

The Zone Food Block Method

Zone food blocks allow you to personalize the Zone Diet to your body by calculating how many grams of protein, carbs and fat you can have per day.

The number of Zone blocks you should eat per day depends on your weight, height, waist and hip measurements. You can calculate your number here.

The average male eats 14 Zone blocks per day, while the average female eats 11 Zone blocks per day.

A main meal such as breakfast, lunch or dinner contains three to five Zone blocks, while a snack always contains one Zone block.

Each Zone block is made of a protein block, a fat block and a carb block.

  • Protein block: Contains 7 grams of protein.
  • Carb block: Contains 9 grams of carbs.
  • Fat block: Contains 1.5 grams of fat.

Here is a detailed guide with different options and how much of each food option is needed to make a protein block, carb block or fat block.

Summary: You can choose to follow the Zone Diet with either the hand-eye method or the Zone Food Block method.

What Foods Can You Eat on the Zone Diet?

A lot of the favorable Zone Diet food choices are similar to those of the Mediterranean Diet, which is one of the healthiest diets on the planet.

In fact, the creator of the Zone Diet has recently released a new book called The Mediterranean Zone, in which he covers the similarities and benefits of the two diets.

Protein

Grilled Salmon

Protein options in the Zone Diet should be lean. Good options include:

  • Lean beef, pork, lamb, veal and game
  • Skinless chicken and turkey breast
  • Fish and shellfish
  • Vegetarian protein, tofu, other soy products
  • Egg whites
  • Low-fat cheeses
  • Low-fat milk and yogurt

Fat

The Zone Diet encourages choosing a type of monounsaturated fat. Good options include:

  • Avocados
  • Nuts, such as macadamia, peanuts, cashews, almonds or pistachios
  • Peanut butter
  • Tahini
  • Oils such as canola oil, sesame oil, peanut oil and olive oil

Carbs

Bunch of Purple Grapes

The Zone Diet encourages its followers to choose vegetables with a low glycemic index and a little fruit.

Good options include:

  • Fruit such as berries, apples, oranges, plums and more
  • Vegetables such as cucumbers, peppers, spinach, tomatoes, mushrooms, yellow squash, chickpeas and more
  • Grains, such as oatmeal and barley
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Summary: Similar to the Mediterranean Diet, Zone Diet food options include lean protein, carbs with a low glycemic index and healthy fats.

What Can’t You Eat on the Zone Diet?

Nothing is strictly banned on the Zone Diet. However, certain food choices are considered unfavorable because they promote inflammation.

  • High-sugar fruits: Such as bananas, grapes, raisins, dried fruits and mangoes.
  • High-sugar or starchy vegetables: Like peas, corn, carrots and potatoes.
  • Refined and processed carbs: Bread, bagels, pasta, noodles and other white-flour products.
  • Other processed foods: Including breakfast cereals and muffins.
  • Foods with added sugar: Such as candy, cakes and cookies.
  • Soft drinks: Neither sugar-sweetened nor sugar-free drinks are recommended.
  • Coffee and tea: Keep these to a minimum, since water is the beverage of choice.

Summary: No food is banned on the Zone Diet, but foods that are not encouraged include those that are high in sugar and starch, are processed, or have refined carbs or added sugar. Water is the recommended beverage.

Sample Food Block Meal Plan for Men

Here is a sample block meal plan with 14 food blocks, for the average man.

Breakfast (4 food blocks): Scrambled eggs with turkey bacon, vegetables and fruit.

  • 2 eggs, scrambled
  • 3 strips turkey bacon
  • 1 ounce of low-fat cheese
  • 1 apple
  • 3 1/2 cups (630 grams) of spinach, cooked
  • 1 cup (156 grams) mushrooms, boiled
  • 1/4 cup (53 grams) onions, boiled
  • 1 1/3 teaspoons (6.6 ml) olive oil

Lunch (4 food blocks): Grilled chicken and egg salad with fruit.

  • 3 ounces (84 grams) grilled chicken, skinless
  • 1 hard-boiled egg
  • Up to 2 heads of iceberg lettuce
  • 1 cup (70 grams) raw mushrooms
  • 1 cup (104 grams) raw cucumber, sliced
  • 1 red bell pepper, sliced
  • 2 tablespoons avocado
  • 1/2 teaspoon walnuts
  • 1 teaspoon (5 ml) vinegar dressing
  • 2 plums

Mid-Afternoon Snack (1 food block): Boiled egg, nuts and fruit.

  • 1 hard-boiled egg
  • 3 almonds
  • 1/2 apple

Dinner (4 food blocks): Grilled salmon, lettuce and sweet potatoes.

  • 6 ounces (170 grams) salmon, grilled
  • 1 cup (200 grams) of sweet potatoes, baked
  • Up to 1 head of iceberg lettuce
  • 1/4 cup (37 grams) tomato, raw
  • 1 cup (104 grams) raw cucumber, sliced
  • 2 tablespoons avocado
  • 2/3 teaspoon (3.3 ml) olive oil

Pre-Bedtime Snack (1 food block): Cottage cheese, nuts and fruit.

  • 1/4 cup (56 grams) cottage cheese
  • 6 peanuts
  • 1/2 orange

Summary: The Zone Diet meal plans break food portions into food blocks, which give you the diet’s proportions of macronutrients throughout the day.

Sample Food Block Meal Plan for Women

Here is a sample block meal plan for the average female, with 11 food blocks.

Breakfast (3 food blocks): Scrambled eggs with turkey bacon and fruit.

  • 2 eggs, scrambled
  • 3 strips turkey bacon
  • 1/2 apple
  • 1 cup (156 grams) mushrooms, boiled
  • 3 1/2 cups (630 grams) spinach, cooked
  • 1 teaspoon (5 ml) olive oil

Lunch (3 food blocks): Grilled chicken and egg salad with fruit.

  • 2 ounces (57 grams) grilled chicken, skinless
  • 1 hard-boiled egg
  • Up to 2 heads of iceberg lettuce
  • 1 cup (70 grams) raw mushrooms
  • 1 cup (104 grams) raw cucumber, sliced
  • 1 sliced red pepper
  • 2 tablespoons avocado
  • 1 teaspoon (5 ml) vinegar dressing
  • 1 plum

Mid-Afternoon Snack (1 food block): Boiled egg, nuts and fruit.

  • 1 hard-boiled egg
  • 3 almonds
  • 1/2 apple

Dinner (3 food blocks): Grilled salmon, lettuce and sweet potatoes.

  • 4 oz (113 grams) salmon, grilled
  • 2/3 cup (67 grams) of sweet potatoes, baked
  • Up to 1 head of iceberg lettuce
  • 1/4 cup (37 grams) raw tomato
  • 1 cup (104 grams) raw cucumber, sliced
  • 2 tablespoons avocado
  • 1/3 teaspoon (3.3 ml) olive oil

Pre-Bedtime Snack (1 food block): Cottage cheese, nuts and fruit.

  • 1/4 cup (56 grams) cottage cheese
  • 6 peanuts
  • 1/2 orange
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Summary: A sample meal plan for women is similar to the plan for men, but has 11 food blocks instead of 14.

How Does the Zone Diet Work?

Fork and Spoon Tied With a Measuring Tape

The Zone Diet claims to optimize your hormones to allow your body to enter a state called “the Zone.”

This is where your body is optimized to control inflammation from your diet.

The purported benefits of being in “the Zone” are:

  • Losing extra body fat as fast as possible
  • Maintaining wellness into older age
  • Slowing down the rate of aging
  • Performing better and thinking faster

Dr. Sears recommends testing three blood values to determine whether you are in “the Zone.”

TG/HDL Ratio

This is the ratio of “bad” fats known as triglycerides to “good” HDL cholesterol in your blood. A lower value means you have more good cholesterol, which is healthier.

The Zone Diet recommends less than 1 as a good value, which is low. A high number for your TG/HDL ratio increases your risk of heart disease (1).

Your ratio for TG/HDL must be tested by a health care professional, such as your doctor.

AA/EPA Ratio

This is the ratio of omega-6 to omega-3 fats in your body. A lower value means you have more omega-3 fat in your blood, which is anti-inflammatory.

The Zone Diet recommends a value between 1.5–3, which is low. A high number for your AA/EPA ratio is linked with a higher risk of depression, obesity and other chronic diseases (2, 3, 4).

You can test your ratio for AA/EPA at home with a kit purchased on the Zone Diet website.

HbA1c, Also Known as Glycated Hemoglobin

This is a marker of your average blood sugar levels over the preceding three months. A lower value means you have less sugar in your blood.

The Zone Diet recommends a value of less than 5%, which is low. A higher HbA1c is linked to a higher risk of diabetes (5).

Your HbA1c must be tested by a health care professional, such as your doctor.

Supplements Recommended

The Zone Diet recommends that you take omega-3 supplements, such as fish oil, to maximize health benefits. They decrease the “bad” LDL cholesterol in your body, and may reduce your risk of other chronic health diseases (6).

The Zone Diet also recommends taking polyphenol supplements, which are molecules found in plants that have antioxidant properties.

The evidence behind polyphenols is mixed and although they may provide health benefits such as reducing the risk of heart disease, they also have risks such as decreasing your iron absorption (7, 8).

Summary: The Zone Diet claims to control inflammation in your body. You can use blood tests to check if you’re in “the Zone.” It is recommended to supplement with omega-3s and polyphenols.

Benefits of the Zone Diet

Tomato, Broccoli, a Bell Pepper and a Tape Measure on Bathroom Scales

Following the Zone Diet has many benefits.

Unlike other diets, the Zone Diet does not strictly restrict any food choices.

However, it does recommend against options that are unfavorable, such as added sugar and processed foods.

This can make the Zone Diet more appealing than other diets for people who struggle with food restrictions.

The recommended food choices for the Zone Diet are quite similar to the Mediterranean Diet. The Mediterranean Diet is supported by evidence as being one of the best for your long-term health (9, 10, 11, 12, 13).

The Zone Diet also provides you with flexibility, since there are two methods of following the diet.

The Zone Food Block method can also help fat loss because it controls how many calories you eat per day. It is well known that controlling your calorie intake helps with weight loss (14, 15).

If you want to find out how many calories you need to eat per day to maintain and lose weight, you can find out here.

Summary: The Zone Diet has many benefits linked with the favorable foods in the diet. It is flexible and may help you lose weight by helping you restrict your calorie intake.

Disadvantages of the Zone Diet

A Pair of Grey Running Shoes

Although the Zone Diet has several benefits, it also has some disadvantages.

First, the Zone Diet makes many strong health claims that are based on the theory behind the diet.

However, there is little evidence to support that the theory produces the purported results (16).

For example, the Zone Diet claims to improve performance. However, a study on athletes following the diet found that, although they lost weight, they also lost endurance and were exhausted faster than others (17).

Reducing diet-induced inflammation to reach “the Zone” is another claim the diet makes. The Zone Diet claims that once your blood values meet their targets, your body would be in “the Zone.”

Although some research shows the diet may improve your blood values, more research is needed before researchers can say this significantly reduces inflammation in the body (18).

There is also little evidence that supports the Zone Diet’s 40% carb, 30% protein and 30% fat ratio as the optimal ratio for fat loss and health benefits.

Another study compared the effects of a Zone-type diet that had 40% carbs, 30% protein and 30% fat to the effects of a diet that had 60% carbs, 15% protein and 25% fat (19).

The study did find people on a Zone-based ratio lost more weight. However, that difference could be due to higher protein intake (20).

Interestingly, the study also found no significant differences in blood values of sugar, fat and cholesterol between the two groups.

This does not match the claims made by the Zone Diet and could mean the improved blood values found in other studies may be due to supplementing with omega-3 and polyphenols, rather than benefits from diet alone.

Summary: The Zone Diet makes hefty health claims. However, there isn’t enough evidence to support them.

Should You Try the Zone Diet?

At the end of the day, choose a diet that best matches your lifestyle.

The Zone Diet could be ideal for you if you want a diet that has similar food options to the Mediterranean Diet, but provides you with clear guidelines to follow.

However, the health claims the diet makes are best taken with a grain of salt.

Although the theory behind the diet may be linked with better health outcomes, there is not enough evidence to say the diet will reduce your risk of chronic disease, slow down aging, improve physical performance or help you think faster.

If you want to try to build healthy eating habits, the Zone Diet may help get you started and help you practice portion control.

Yet what matters in the long term is basing your diet around whole and unprocessed foods — regardless of the name of the diet.

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