OVERVIEW

Dr. Weyrich finds PhD. Barry Sears' "ZONE" diet the most compelling and scientifically based of the various diets that have been published in the past quarter century.

The ZONE diet is based on a dialectic balance between opposing food-stuffs and opposing hormones. Just as in Traditional Chinese Medicine, the Yang must be balanced by the Yin, in the ZONE diet carbohydrate foods must be balanced by protein foods, insulin must be balanced by glucagon, and Omega-3 fats must be balanced by Omega-6 fats. This leads to a balance of anti-inflammatory and inflammatory eicosanoid hormones, and optimizes health and longevity.

The ZONE diet can be contrasted with the Ornish diet, which overemphasizes carbohydrates, and the Atkins or keto diet, which overemphasizes protein and fat.

On the other hand, the Zone diet can be adapted to overlay other types of diets, such as vegan, Mediterranean, or paleo diets in such a way as to simultaneously satisfy the criteria for both diets simultaneously.

The basic rules of the ZONE diet are simple:

  1. Every meal should be designed so that the number of calories derived from protein is determined based on lean body mass and the person's activity level. Typically, this constitutes about 30% of the calories in the meal, with the exact percentage varying according to the individual's genetic predispositions.
  2. Every meal should balance the amount of calories from protein with about 4/3 the amount of calories derived from complex (non-starchy) carbohydrates. Typically, this constitutes about 40% of the calories in the meal, with the exact percentage varying according to the individual's genetic predispositions.
  3. The remainder of the calories in the meal should be derived from "good" fats (and stored fat if weight loss is desired). Typically, this constitutes about 30% of the calories in the meal, with the exact percentage varying according to the individual's genetic predispositions.
  4. The total calories consumed per day should be divided proportionately between three meals and two snacks, with no more than 5 hours between each meal or snack.
  5. Eat breakfast within an hour of awakening, lunch about 5 hours later, have a late afternoon snack, dinner, and then a bed-time snack.

These rules can be strictly applied by consulting tables of food composition and weighing all portions (discussed in DETAILS below), or can be estimated using what PhD. Sears calls the "hand-eye" method - which is as follows:

  1. For a meal, choose a portion of a lean protein source (meat or tofu etc) about the size and thickness of your palm, and put it on your plate.
  2. Add to the plate twice as much complex carbohydrates (ideally various colors).
  3. Add a splash of a "good" oil, such as olive oil or a dollop of guacamole.
  4. Enjoy.
  5. A snack should be about 1/3 the size of each of the above meals.

If you prefer a more precise number-crunching approach, please see another method in the DETAILS section below.

If your are in the "balance-ZONE", you will not feel hungry or fatigued within each 5-hour window. Otherwise, consult with your nutritional advisor regarding how to tweak the above parameters to your individual genetic predisposition.

Initially, it may seem like a lot of effort to figure out portion sizes and recipes that keep you in the ZONE. But most people have fairly consistent dietary habits, eating maybe only a dozen different meals on a regular basis. Once you have figured out your particular dozen meals, you are set to eat in the ZONE the rest of your life with little added effort. Or, if you enjoy trying new recipes all the time, there are many available recipe books for ZONE-friendly meals that you can try out, or adapt as you choose.

DETAILS

Protein

Everyone should consume enough protein at each meal to maintain their muscle mass (including heart muscle!). If your goal is weight loss, follow the ZONE diet to lose fat, not muscle. You know if you are on the right track if your clothes get too loose and you have to down-size your wardrobe, even if your weight doesn't go down.

So how much protein do you need? That depends on what is called your lean body mass. PhD. Sears explains how to calculate your lean body mass using a tape-measure (e.g. [Sears1995, pg 213]). Dr. Weyrich prefers to use a biometric scale that can quickly estimate percent body fat. Dr. Weyrich personally uses the Go to Omron Scale Omron Scale.

Then use the formula:

Lean Body Mass = (100% - % Body Fat) * Weight in Pounds / 100%

After you know your lean body mass, you need to estimate your activity factor using the table provided by [Sears1995, pg 261]:

Activity LevelActivity Factor (g/lb)
Sedentary0.5
Light fitness training such as walking0.6
Moderate training (3 times a week or sports participation)0.7
Daily aerobic training or daily moderate weight training0.8
Heavy daily weight training0.9
Heavy daily weight training plus either intense sports training or twice-a-day intense sports training1.0

Finally, after you know your activity factor, you can estimate your daily protein need using the formula:

Protein Need [grams/day] = Lean Body Mass [lb] * Activity Factor [g/lb]

More is NOT better! Increasing your protein intake above your protein need will result in the body converting the extra protein into fat.

Carbohydrates

Once you know your protein need, calculating your complex carbohydrate need is simple. Assuming that you have typical genetic propensities (30% protein and 40% carbohydrate):

Complex Carbohydrate Need [grams/day] = (40%/30%) * Protein Need [grams/day]

Fats

After doing the above calculations, you can calculate the amount of fat intake needed to maintain your current fat percentage (bear with me if you want to loose fat!) In order to maintain your current fat percentage while staying in the ZONE, assuming that you have typical genetic propensities (30% protein, 40% carbohydrate, 30% fat):

Percent Fat Need = 100% - Percent Protein Need - Percent Carbohydrate Need

= 100% - 30% - 40% = 30%

Since fat contains about 9 Calories/gram and protein contains about 4 Calories/gram, we can estimate the number of grams of fat per day we need to maintain our current fat store:

Fat Need [grams/day] = (4/9) * Protein Need [grams/day]

ZONE-Blocks

[Sears1995, pg 227ff] defines what he calls "ZONE-blocks" for protein, carbohydrates, and fats. The idea is that all meals should be composed of an equal number of blocks of each macronutrient:

  • Protein: 1 Block contains approximately 7 grams protein (uncooked)
  • Carbohydrates: 1 Block contains approximately 9 grams of complex carbs
  • Fats: 1 Block contains approximately 1/3 teaspoon of fat * (4.6 grams/teaspoon) = 1.5 grams of fat [Sears1995, pg 237].

Note that by using PhD. Sears' block system, the number of grams in a block is always defined the same, but depending on the personal daily protein, carbohydrate, and fat need of each person, the daily number of blocks of each macronutrient that are needed by that person will be different.

Example

Applying the above calculations to the example of Dr. Weyrich himself, we have:


Weight in Pounds = 183.4lb
% Body Fat = 28.6%
Lean Body Mass = (100% - % Body Fat) * Weight in Pounds / 100% = 131lb
Activity Factor = 0.5
Protein Need [grams/day] = Lean Body Mass [lb] * Activity Factor [grams/lb] = 65.5grams/day
Complex Carbohydrate Need [grams/day] = (40%/30%) * Protein Need [grams/day] = 87grams/day
Fat Need [grams/day] = (4/9) * Protein Need [grams/day] = 29grams/day

Using PhD. Sears' ZONE-Blocks for the calculations we have:

Blocks of protein/day = 65.5grams/day * (1 block/7grams) = 9.4 blocks/day
Blocks of carbohydrates/day = 87grams/day * (1 block/9grams) = 9.7 blocks/day
Blocks of fat/day = 29grams/day * (1 block/1.5grams) = 19 blocks/day

Personal Blocks

Dr. Weyrich suggests a somewhat different approach. Instead of using PhD. Sears' standardized block sizes, and then adjusting the recipes to the number of blocks needed by each individual, Dr. Weyrich suggests defining personal block sizes for each person based in their individual macronutrient needs, according to the formula:

  • Protein: 1 Block = Personal Daily Protein Need [grams/day] / 11 [blocks/day].
  • Carbohydrates: 1 Block = Personal Daily Carbohydrate Need [grams/day] / 11 [blocks/day].
  • Fats:: 1 Block = Personal Daily Fat Need [grams/day] / 11 [blocks/day]. Note that this number is approximately twice that of PhD. Sears' value - apparently Sears discounted the amount of fat in order to build in weight-loss by obtaining about half the fat Calories from stored fat.

By using the above personal block definitions, everyone will need exactly 11 blocks/day of each macronutrient. In this way, all recipes can be written in terms of personal blocks, and the actual measurement can multiply the number of blocks specified by personal block sizes specified above.


Using Dr. Weyrich's Personal-Blocks for the calculations we have:

Personal-Block of protein = 65.5grams/day / 11 [blocks/day] = 5.95grams protein/block
Blocks of carbohydrates/day = 87grams/day / 11 [blocks/day] = 7.91grams carbohydrates/block
Blocks of fat/day = 29grams/day / 11 [blocks/day] = 2.64 grams fat/block (use less than a block if weight loss is desired).

Therefore, Dr. Weyrich can maintain his current weight by eating 3 meals containing 3 blocks of each macronutient plus 2 snacks containing 1 block of each macronutrient; or he can lose weight by using less fat.

This works best when one has a food scale and a calculator (or cell phone with calculator function) in the kitchen. Dr. Weyrich uses this Go to food scale food scale.

REFERENCES