Zone Blocks method

Dr Sears designed his blocks method to make it easier to prepare meals that are a suitable size and have a favourable balance of macronutrients.

Please remember this is just a guide – you don't have to precisely measure everything every meal! And after you've measured foods a few times you'll get a feel for sizes and won't need scales or measuring cups any more.

It's based on 40:30:30

This food blocks method is designed to produce meals with Dr Sears' desired ratio of:

40% Carbs : 30% Protein : 30% Fat

Three important points:

  1. This is a ratio of energy, or calories, not volumes or quantities of food. One third of your plate will not be filled with butter!
  2. This ratio is intended for someone hoping to lose body fat. If you don't want to lose weight you may have to eat more fat, which will change this ratio.
  3. Again, this is just a guide to get you started. If you have trouble with certain meals that's fine, a bit more or less here and there won't hurt.

I will talk more about this ratio in the theory section.

Food blocks

If you have a look at the first few columns in my food table you'll see most foods are classifed as either a carbohydrate or a protein or a fat, and the amount next to each food represents 1 Zone 'block'.

One block of a carbohydrate food supplies about 9 grams of available carbs, one block of a protein food supplies about 7 grams of protein, and one block of a fat food supplies 3 grams of fat. Because fat supplies more calories per gram than carbs and proteins a meal with equal numbers of blocks of carbs and protein and fat will have roughly the 40:30:30 balance of energy.

Example 2 block Zone meal

We call that a 2 block meal. Unfortunately it can be confusing because that looks like it contains 6 blocks, but a 2 block meal contains 2 blocks each of protein carbs and fat.

It may help to think of each 1 block containing 3 'mini-blocks' – 1 mini-block of protein + 1 mini-block of carbs + 1 mini-block of fat.

Example 4 block Zone meal

It's easy once it clicks.

How many blocks?

How much we eat is based on how much protein we need, which is based on how big and active we are.

Specifically, we take our lean body mass in pounds and multiply it by an activity factor (explained below) to get a number of grams of protein to eat per day. Then we divide that by 7 to get the number of blocks to eat per day, as there are 7 grams of available protein in 1 Zone block.

Quick estimates: If you don't want to fuss about with these calculations and you're an average size and don't do a lot of exercise you can start with 11 blocks for women and 14 blocks for men then skip to 'Making meals' below.

Lean body mass

Our lean body mass is simply our total weight minus the weight of our body fat.

There are various methods to estimate our percentage of body fat using some simple body measurements, the calculator at Dr Sears' site is accurate enough and will do all the block calculations for you too (it's free but you will have to register), or here's another one that uses a few extra measurements and may be slightly more accurate.

Then with two quick calculations:

  1. % body fat ÷ 100 x total weight = weight of fat
  2. total weight - weight of fat = lean body mass
    (This has to be in pounds – if you've done the calculations in kilograms just multiply the result by 2.2 to convert it to pounds. Sorry, it's an American system.)

Example: You're 78kg and 32% percent body fat, 32 ÷ 100 x 78 = 25kg of fat, lean body mass = 78 – 25 = 53kg. And to convert to pounds, 53kg x 2.2 = 117 pounds.

Activity factor

To estimate how many grams of protein to eat per day multiply your lean body mass, in pounds, by your own activity factor:

  • 0.5Sedentary – Office work with no extra exercise
  • 0.6Light activity – Some walking or light exercise
  • 0.7Moderate – Sport or exercise for 1.5 hours a week
  • 0.8Active – Exercise for 1.5 – 2.5 hours a week, or a physical job.
  • 0.9Very Active – Exercise for over 2.5 hours per week.
  • 1.0Elite Athlete – Elite level or heavy weight training.

Example: Say you play tennis once a week and jog or go to the gym once a week, your activity factor would be a moderate 0.7, so 117 pounds x 0.7 = 82g of protein per day.

Protein grams per day

You now have an estimate of your number of grams of protein to start eating per day. Finally divide by 7 to get your total number of protein blocks to eat per day.

Example: 82g ÷ 7 = 11.7, and we'd round that up to 12 blocks per day.

Note: 11 blocks should be the minimum for all adults, even if your calculations work out less than that, still eat 11 blocks per day. (11 blocks is only 1100 calories, not much at all.)

Making meals

Now we divide the total number of blocks up into our daily meals, often it will be 3 main meals and 2 snacks, but you can adjust it as necessary. To continue with our example of 12 blocks per day, you might break that up like this:

  • 3 block breakfast at about 7.00am
  • 1 block snack at 10:30am
  • 3 block lunch at 12:30pm
  • 1 block snack at 4:00pm
  • 3 block dinner at 7:00pm
  • 1 block snack at 9:30pm

Or you could have...

  • 3 block breakfast
  • 3 block lunch
  • 3 block afternoon meal
  • 3 block late dinner


  • 2 block snack before early exercise
  • 3 block mid morning breakfast
  • 3 block late lunch
  • 4 block dinner

It's generally better to have more meals spread throughout the day than one or two big ones, and try not to let five hours pass without eating, but other than that it's really up to you and your lifestyle.


A 6 block meal is about the maximum, and would only be suitable for someone with a very big lean body mass or someone doing intense physical training.

You know it!

Now you're ready to get going! Or if you want more info on the best types of food to eat keeping reading the what to eat section...