Thoughts on the Zone Diet

The Zone Diet seeks to create a fixed mix of macros by specifying fat, carbs and protein levels. The starting point is:

The numbers are in percentage of calories. On a “standard” 2000 calorie diet that would be:

  • Carbs = 2000 * 0.40 = 800 calories (200 grams)
  • Protein = 2000 * 0.30 = 600 calories (150 grams)
  • Fat = 2000 * 0.30 = 600 calories (67 grams)

Zone vs Standard American Diet (SAD)

According to the CDC (Trends in Intake of Energy and Macronutrients in Adults From 1999-2000 Through 2007-2008):

In 2007-2008 the average energy intake for men was 2,504 kilocalories (kcals) and for women it was 1,771 kcals.

The average carbohydrate intake was 47.9% of total kilocalories (% kcals) for men and 50.5% kcals for women; average protein intake was 15.9% kcals for men and 15.5% kcals for women; average total fat intake was 33.6% kcals for men and 33.5% kcals for women; and average saturated fat intake was 11.0% kcals for men and 11.1% kcals for women.

That means the Zone Diet is lower in carbohydrates, much higher in protein, and a lower fat than the Standard American Diet (SAD).

Macro SAD (Men) SAD (Women) ZONE Difference
Carb 47.9 50.5 40 Zone Lower
Protein 15.9 15.5 30 Zone Much Higher
Fat 33.6 33.5 30 Zone Lower

The main lever of the Zone then appears to be Protein. Doubling someone’s Protein should do some very good things for their health. Added to that is the advantage of the lower number of total calories on the zone.

But would the Zone be a good thing for a Type 2 Diabetic? Certainly it would help some who are diagnosed as pre-diabetic. Anything they do to reduce their carbohydrate consumption will help their pre-diabetes.

Zone vs Ketogenic Diet

The Ketogenic diet has various protein goals depending on you who follow. For a 200 lb male typical numbers would be (using a higher level of protein in this example):

Macro grams kCal/macro Calories % Cals
Carb 20 4 80 4%
Protein 160 4 640 32%
Fat 142 9 1280 64%

Where the two diets differ are their fat and carbohydrate macros.

Macro ZONE Ketogenic
Carb 40% 4%
Protein 30% 32%
Fat 30% 64%

Carbohydrate Effects on a Type 2 Diabetic

Carbohydrates raise blood sugar and therefore Insulin levels much more dramatically in a Diabetic than in a non-Diabetic person. That’s what makes a person an Diabetic. Before I went on the Ketogenic diet I was averaging only 100 grams of carbohydrates per day. I know this since my Insulin pump required me to enter any carbohydrates I ate. And, in spite of being on an average of 100 units of Insulin a day, my blood sugars were all over the place.

My highs were over 200 and my lows never got to 100. Around the start of August I went on the Ketogenic diet. For me, that was going from 100 grams (on the average) of carbohydrates a day to less than 20 grams. I was also not tracking the other macros (fat, protein). Here are my blood sugar numbers from the first three months of the Ketogenic diet.

That chart is the very definition of stable blood sugars. It took being at 20 grams or less of carbs a day to get stable. And before the Ketogenic diet I was nowhere near the Zone Diet carbohydrate levels. I can only imagine how messed up my blood sugar numbers would have been if I had been on the “balanced” zone diet.


CrossFit and Nutrition

CrossFit really gets nutrition.  A few caveats about this video:

  • Not sure I completely agree with their body fat percentage goals for older people – or at least making it the priority.
  • Also their initial macro mix has a much higher carb amount (1/3 of calories from carbs) than what Type 2 Diabetics should eat.

Video Points

  1. Eat real food.
  2. Not too much of it.
  3. Mostly plant based.
  • Living = grew out of the ground or had eyes.
  • Stay out of the middle aisles of the supermarket.
  • No man-made food like substances.
  • Don’t use your macros as a way of avoiding eating right.
    • Macros are your mix of Protein/Carbs/Fats within overall calorie limit.

Metabolism and Aging

Intuitively, we all know that our metabolism slows as we age. Did you though this has been quantified? Here’s the chart of Basal Metabolic Rates in men and women vs age:

So this, at least in part, demonstrates why it is harder at 50 to lose weight than when we are 20. For a man of 20 their BMR is about 46 and the same man (at the same size) their BMR is around 38. That’s only 82% of the age at 20. So, yes, it is harder to lose weight since you have to eat less to lose weight than you did when you were young, but it is not at all impossible.

Even if you are older, you can do it.


mPSMF – Weight Loss Progress

My modified Protein Sparing Modified Fast is moving along very well. Here’s my weight loss chart (from Cron-o-meter):

I had a nice drop over the past couple of days. Note that I started teh food diary in Cron-o-meter on Oct 24th. That may contribute to the losses due to the increased attention to intake. Before that I was using my own spreadsheet to track diet.  Cron-o-meter may be making me more accurate with measuring food intakes.

Goals Changes?

My newly adjusted weight goal is 170 lbs. That’s 144.4 lbs of Lean Body Mass and 15% body fat. That’s in the middle of the athlete range of body fat and on the low end for an older man like myself.

[Later – Updated goal to 20.9% based on Ideal Body Fat percentage]

Modified Protein Sparing Modified Fast (PSMF)

I am calling what I am doing a Modified Protein Sparing Modified fast (PSMF) since the classical PSMF does not factor in fat oxidation rates.

I think it’s useful to factor in fat oxidation rates since that’s the maximum amount of fat a person can pull from their body per day. See my post, “Hypophagia – How much fat can I lose in a day?” for details.

Lyle McDonald’s Rapid Fat Loss Book

Lyle McDonald’s book “Rapid Fat Loss” (RFL) simply puts people on a particular amount of protein depending upon what stage of the diet a person is on. As the diet goes on and a person loses body fat their protein amount increases on Lyle’s method. So basically, his method is Very Low Carbs (except certain unlimited green veggies).

I think the fault in Lyle’s method isn’t so much that it leads to excessive protein consumption. Some would say that there’s no such thing as too much protein and within limits they could be right.

I think the fault in Lyle’s method is not factoring in the limits of hypophagia. Drop your calorie intake too low (below what the body can provide) and something has to give. If you can’t lose more than a particular amount of fat per day then why would you eat at a lower calorie amount than that?


PSMF – A Day’s Food/Supplements/Exercise/Biometrics

I’ve completed a day of logging everything with CRON-o-meter. Here’s the data entry part:

Bio-metrics were Weight, Body Fat percentage (from the scale), Body Temperature (used to determine if metabolism has dropped) and Blood Glucose.

Exercise was logged (CrossFit with warm-up and the resistance training portions).

Finally, the food I ate was carefully and completely logged. So how did I do compared to my goals? For overall calories I overshot by 2%. That’s great since I should never go under with PSMF.

The overall breakdown was also pretty good. I went under on my fat and over on my protein which balanced each other out. I did not exceed the carbohydrate number (net grams less than 20). That put me at a net deficit of 1131 calories. That would be about 2 lbs per week of loss.


Protein Sparing Modified Fast (PSMF) – Two Weeks In

I am two weeks into this Protein Sparing Modified Fast. How do the results stack up so far? My current Scale (vs Original scale) numbers are:

  • Weight: 198.6 (203.3) 4.7 lbs down, Predicted Weight: 197.5 lbs.
  • Body Fat: 31.2 (32)%. down 1.6% of body weight (-3.2 lbs), Predicted Body fat loss: -5.02 lbs.
  • Muscle:  28.2 (27.6)%, down -0.2 lbs.

That’s pretty good. 6.3% of loss was muscle loss, 93.7% of loss was fat loss. So this WOE is definitely protein sparing. Just not hitting the amount of body fat loss that the table predicts. Will need to scale the time to achieve my goals. Interestingly enough the protein loss was very similar to the number reported by Yang on a water-only fast. Still it’s hard to draw a definitive conclusion from a bathroom scale.

Water retention has been relatively good with my %H2O going up from 36.9% to 37.7% (which correlates to an actual weight drop of 0.26 lbs). This isn’t a diet which dumps a lot of water plus I had just been on a loss before starting this WOE. Also, I’ve been able to keep up with needed electrolytes. I may even be overdoing them. In PSMF it seems easier to take care of electrolytes than a water-only fast. The Whey Protein Powder has a lot of the electrolytes in them plus vitamins. Protein itself may help and the fiber in green vegetables probably contributes. I’ve been eating Chia Seeds to keep up the fiber as well.

Dietary compliance has been pretty good/easy. I have been consistently hitting or slightly exceeding my daily macros within a few percentage points. It’s a bit of a juggling act and some pain to do daily tracking of the macros, but my spreadsheet makes it easier.

Exercise (CrossFit) has been varied but well tolerated. I am mostly in the phase of neurological adaptations now and on occasion I do something right enough to not be told to change it. Not putting on muscle mass isn’t all that big of a deal in this phase of my adaptation. I don’t see myself becoming a body builder and I don’t want too much muscle mass anyway. But I can imagine that doing body weight things like chinups and pushups will be a heck of a lot easier with 28 less lbs of fat. Running is already getting easier.

Sticking with my initial goal of 15% body fat. Scale says 31.2% which is significantly different than the USN calculator value of 24.1%. This article suggests that bathroom scales include the water that is in fat cells in their water results. That may give a clue as to why the fat number and water numbers are not quite what is expected. Particularly if some fat is being replaced by water (See the Whooosh Effect).

Update (2017-09-28): Link to Lyle McDonald’s article on the whooosh.

Protein Sparing Modified Fast Calculator

I put together the previous formulas into one single webpage, the Protein Sparing Modified Fast Calculator. I’ve put my own current numbers into the calculator. Just hit the “Calculate” button to see my numbers. Feel free to try it out with your own numbers and see if it helps you figure out any of this. I don’t see the numbers you enter nor are they stored in any database. All of the calculations are done on your phone web browser or Internet browser (Firefox and Chrome works but Internet Explorer doesn’t).

If you find any errors, please let me know. I tried it with my own numbers and they make sense but I didn’t have a woman’s secret numbers to check.

Here’s a decent introduction to the Protein Sparing Modified Fast (PSMF). I only take exception to one point which is the question of how long you can do a PSMF. They say you can’t do it for an extended period of time. If you continually re-calculate your numbers you should be able to fine tune for maintenance levels. This calculator makes that re-calculation relatively easy. Here’s the results I got for my numbers.

Your Scale and Metabolism Numbers

Current Weight: 199.8 lbs
Goal Weight: 171.3 lbs
Lbs from Goal Weight at start: 28.5 lbs
Body Fat at start: 25.4%, 50.8 lbs
Lean Body Mass (LBM): 149.0 lbs
Basal Metabolic Rate (BMR): 1818.0 cal/day
Initial Total Daily Energy Expenditure (TDEE): 2500 cal/day
Initial Maximum Fat Loss on Protein Sparing Modified Fast: 0.45 lbs of body fat per day


Protein Sparing Modified Fast (PSMF) Dietary Macros (per day)

It is very important on the PSMF that you eat at least the macros listed here. If you go below these numbers you risk lowering your metabolism and you actually can’t lose body fat any faster. Attempting to be just above the numbers is OK.

Protein: 119.2 g (476.8 cals)
Carbs: 20 g (80 cals)
Fat: 40.9 g (367.7 cals)
Your total Dietary Calories are 924.4 cals for maximum fat loss.

If you consume 216 g (1943 calories) of fat you will stay at your current weight.At your goal weight you will be able to consume 119.2 grams of Protein, 20 grams of Carbs, and 176.3 grams of Fat.


Can You Fast?

One important question to ask when considering extended fasting is whether or not you have sufficient body fat to fast.

You currently use 2500 cal/day. You have 1575 calories per day available from your body fat for maintenance. You have less calories available from body fat than your daily requirements and may not be able to fast. If you fast, your body may drop your base metabolism, energy expenditures or may consume protein stores. You will be -924 calories short per day

The thermic effect of food contributes somewhere from 5-20% of your current TDEE number so if you are fasting that can reduce your TDEE. Reducing your TDEE by 10% would result in you using 2250 calories per day. Calculating in a 10% Thermic Effect of food still leaves you in a caloric deficit during fasting. The Protein Sparing Modified fast solves this issue by providing the calories needed for the deficit.

How Much Muscle Can You Gain?

The Maximum Lean Body Mass that you can carry on your frame is 186.5 lbs at your goal of: 15.0% Body Fat. That would be a weight of 214.5 lbs.


Use this information at your own risk and with the advice of your medical professional. We are not doctors nor do we pretend to be one on the Internet. We do not take responsibility for errors in these calculations. We do not guarantee that these numbers will work for people at the extremes of the ranges. If you discover an error in calculation, please let us know through email: keto at land-boards dot com.

So Low Fat Then?

NO – Not Low Fat

What am I suggesting? Is it Low Fat? Nope. To review I am suggesting a diet of:

  • Less than 20 grams of carbohydrates per day
  • Adequate protein – for me 115 grams of Protein a day (KetoGains Protein Levels)
  • Enough fat to maintain Total Daily Energy Expenditure (TDEE) levels (TDEE Calculator)
    • Some of this fat comes from body fat
    • The remainder of the fat comes from dietary fat

This may mean a very low level of dietary fat at the beginning of the way of eating. It will progress towards a proper level of fat to maintain the goal weight. But don’t fear – you will still have plenty of high quality fats to consume from your own body.

The Goal?

There’s two complementary goals that are possible. Either we have the goal of a reaching a certain weight or of reaching a certain body fat percentage. These two numbers turn out to be directly related to each other. That’s because your weight is the sum of your Lean Body Mass (LBM) and your Fat Mass. If you hold your LBM constant and reduce your Fat Mass it will reduce your body weight by the same amount.

An Example of the Goal

The math is pretty straightforward but an example could help.

Say you are a 200 lb male with 150 lbs of LBM. Your fat mass is 50 lbs. You have 25% body fat. If you want to go to 15% body fat that means you must lost 10% of your weight or 20 lbs. Your target weight at 15% body fat is 180 lbs.

Simplified Steps

  1. Use your scale to find your weight. Weight ________ lbs
  2. With a tape measure:
    Height______________ in
    Neck ________________ in
    Waist ______________ in
    Hips (if you ware a woman) _________________ in
  3. Plug in your measurements from step 2 into USN BodyFat Calculator.
    Lean Body Mass = ________________ %
    Body Fat =_________________%
  4. Calculate your max fat loss by multiplying your Body Fat from Step 3 by 31
    Body Fat __________ lbs x 31 cals/lb = ____________ calories
  5. Weight loss per day = number (step 4)  ______ / 3500 = _____
    (This number should be a fraction around 0.5 for many people).
  6. Calculate your LBM.
    LBM = Weight (step 1) _________ minus Body Fat (step 3) _____ = ________ lbs
  7. Calculate your TDEE = ___________  calories
  8. Your calories from carbs should be less than 20 x 4 = 80 calories.
  9. Calculate your protein needs from using one of the constants from KetoGains FAQ page Protein Needs section
    0.69 to 0.8 g / lb of LBM – sedentary person
    0.8 to 1.0 / lb of LBM – mildly active
    1.0 to 1.2 / lb of LBM  – bodybuilders, etc
    Protein Needs (0.69 to 1.2) _____________ x LBM (step 5) __________ = _______________ grams
    Protein calories = 4 x Protein grams __________ = ______ calories
  10. Calculate the total fat calories you can consume each day (both fat from body and fat from diet.
    TDEE (step 6) _______ minus carbs (step 7) ________ minus protein (step 8) = ____________ fat calories
  11. Calculate the calories of fat that you can consume the first day.
    Total fat calories (Step 10) ______ minus Calories available from your body (Step 4) ________________ = ___________ calories

Me as an Example

  1. Use your scale to find your weight. Weight [200] lbs
  2. With a tape measure:
    Height [71] in
    Neck [16] in
    Waist [40] in
    Hips (if you are a woman) [I am Not a woman] in
  3. Plug in your measurements from step 2 into USN BodyFat Calculator.
    Lean Body Mass [148] lbs
    Body Fat [26] %
  4. Calculate your body fat
    Weight _________ lbs times
  5. Calculate your max fat loss by multiplying your Body Fat from Step 3 by 31
    Body Fat [] lbs x 31 cals/lb = ____________ calories
  6. Weight loss per day = number (step 4)  ______ / 3500 = _____
    (This number should be a fraction around 0.5 for many people).
  7. Calculate your LBM.
    LBM = Weight (step 1) _________ minus Body Fat (step 3) _____ = ________ lbs
  8. Calculate your TDEE = ___________  calories
  9. Your calories from carbs should be less than 20 x 4 = 80 calories.
  10. Calculate your protein needs from using one of the constants from KetoGains FAQ page Protein Needs section
    0.69 to 0.8 g / lb of LBM – sedentary person
    0.8 to 1.0 / lb of LBM – mildly active
    1.0 to 1.2 / lb of LBM  – bodybuilders, etc
    Protein Needs (0.69 to 1.2) _____________ x LBM (step 5) __________ = _______________ grams
    Protein calories = 4 x Protein grams __________ = ______ calories
  11. Calculate the total fat calories you can consume each day (both fat from body and fat from diet.
    TDEE (step 6) _______ minus carbs (step 7) ________ minus protein (step 8) = ____________ fat calories
  12. Calculate the calories of fat that you can consume the first day.
    Total fat calories (Step 10) ______ minus Calories available from your body (Step 4) ________________ = ___________ calories


Do Calories Matter?

The first question is “Do Calories matter in what?”. If the “what” is weight-loss then the question is, “Do Calories matter in Weight-loss?”.

The answer is both yes and no. The standard formula Calories In minus Calories Out has many problems including:

  • Doesn’t differentiate between the sources of calories. In this formula 1000 calories of seven layer chocolate cake is the same as 1000 calories of broccoli (although try to eat 1000 calories of broccoli sometime).
  • At a finer level, doesn’t differentiate between the macro-nutrient mix of two things. Is a 200 calorie bag of chips really the same as a 200 calorie bag of macadamia nuts? The chips are carbs and fat as are the nuts but the proportions of fats and carbs are completely different between the two.
  • Within a particular macro-nutrient it also doesn’t differentiate between types of macro-nutrients or how the body processes them.

So where/how do calories matter?

Since the subject of this BLOG is largely Ketogenic diets it is a given that the Low Carb (less than 20 grams of net carbs a day) is the baseline. There’s plenty of science that shows this is an effective and safe diet. But what does that leave? There are only three macro-nutrients (and we aren’t counting the fourth which is alcohol) so that only leaves fat and protein.

Let’s Look at Protein First

Here’s where it gets controversial or fun, depending on your own tolerance for different opinions. You need some amount of protein to maintain your Lean Body Mass. Fasting has been shown to be sparing of lean body mass, but there’s some minimal loss on longer fasts. At one end of the spectrum is Dr Jason Fung who’s patients are often older and present to him with diabetes and other metabolic disorders. He prescribes a limit on protein (How much protein is excessive?):

The average necessary would be 0.6 g/kg/day (around 50 g/day) and LESS if you are trying to lose weight.

The value of 0.6g/kg of body mass translates to 0.27g/lb of body mass. Note Fung’s number is not for Lean Body Mass, but current weight. Let’s round to 0.3 to make the math easier here.

At the far other end are bodybuilders who have much higher macros. But the focus here is ketogenic eating, Here is the KetoGains suggested intake of protein (KetoGain FAQ):

*Sedentary people: 0.69 to 0.8g per lean pound
*Mildly active or doing endurance / strength training: 0.8 to 1.0g per lean pound
* Heavy strength training / bodybuilders / PSMF: 1.0 up to 1.2g per lean pound

So picking the middle number would be 0.9g/lb of LBM. There’s no easy translation between LBM and body weight since it varies greatly person to person. The formula is:

Body weight times (1-fat percentage) = Lean Body Mass (LBM)

For the sake of simplification, let’s assume that the person has 25% fat. Their LBM is 0.75 times their body weight. For a 200 lb person that would be an LBM of 150 lb.

The protein recommendation of Dr. Fung for maintenance is then 200 x 0.3g/lb or 60 grams. The protein recommendation of KetoGains would be 150 x 0.9 = 135 or a bit more than twice that of Dr Fung.

Note the different goals. Dr. Fung’s number is based on the goal of maintenance of LBM and the KetoGains number is based on body recomposition or growth in muscles.

In the end this is a fixed value which should be adhered to – if possible on a daily basis.  And what this means is that the number of calories (4 times the number of grams of protein) is also a fixed number and is specific to your current body weight, etc. If you are a 200 lb male with 30% body fat that translates to 135 grams a day (KetoGains model).

The Only Thing Left is Fat

And surprisingly, fat is also controversial. But it really shouldn’t be. The standard keto advice is eat until satiety. But for many of us that’s a hard point to discover. We’ve eaten until we are stuffed for so long that we are barely able to do otherwise. And fat becomes what we use to feel really full. And fat is very dense.

The Problem with eating too much fat is that we don’t pull fat stores from our bodies when we overdo fat. That is why most of us stall in our losses. We don’t gain weight if we keep low carb because it’s really the carbs which make us fat not the dietary fat. But we are not losing weight either.

How Much Fat Should We Eat?

If you are asking this question it’s because the standard “Eat till satiety” isn’t working for you any longer. In the beginning it worked well but the real reason is that your body had a lot of fat stores to pull from. As we go on in this Way of Eating our bodies have less and less reserves of fat to eat.

There’s a constant called the fat oxidation rate which limits our ability to pull fat from our bodies (A limit on the energy transfer rate from the human fat store in hypophagia). That number is 31 calories per lb of fat mass per day. If you have 50 lbs of fat mass you can only pull around 1500 calories a day from that fat mass. On a long fast, if you pull more calories that comes either out of dropping your metabolism or your body’s protein stores. There are no other sources. And usually it is your metabolism which drops. Some of this is made up by the thermogenic effect of food (you are not burning energy to eat food).

So some of us have tried doing reduced calorie diets without concern for our macro-nutrients. We don’t need carbs (we are keto, right) so there’s only two choices when reducing calories. Either we reduce protein or we reduce fat. If we spare the protein by eating enough (see above) then we have to strike the balance at the cost of lowering our fat consumption.

And lowering fat consumption makes a lot of sense. It’s often easy to not put a stick of butter on a pile of broccoli. It tastes just as good if you have been doing keto for a long time and in essence, the fats are just wasted calories. They won’t make you fat (it takes carbs plus fat to make you fat) but they won’t make you thinner either.

The amount of fat we should eat should be set by the maximum rate of loss that we can do through fat oxidation. You can always choose to go slower, but how many people want to do that? A cheat day would consist of over consuming fat which would be a stall and not a weight gain. But you don’t need to cheat.

The Maths

The Math is described here. In outline it works like this:

  • Get some measurements (Weight, simple body tape measurements)
  • Determine your assumptions (Base Metabolic Rate, Protein needs)
  • Set your goal (Body fat percentage is the sole goal)
  • Run the numbers to determine the results (end weight, weight loss time, macros for each day)
  • Pick your foods to reach your goals depending on each day’s needs
  • Chart your progress as you do it

The Don’ts

  1. Don’t use this information to help your anorexia or some other eating disorder. There’s some ways to help with that like not looking in a mirror but look at a picture of yourself to see what you really look like to others. I did that and I looked fat in the viewfinder but not fat in the picture itself. Same with mirrors.
  2. Don’t set unreasonable goals. Don’t go for 5% body fat. There are safe numbers out there for body fat percentages. You are may not be the best judge of what is good for you (particularly if you have a food disorder). Trust those numbers out there and not your own perceptions of whether or not you are fat.
  3. Don’t try to cook the numbers. By that I mean don’t try to run at a calorie deficit to get it done sooner.
  4. Don’t just run the numbers once and stick to the same pattern for the next three months. At least recalculate the numbers and readjust weekly. The numbers shift quickly on this method. You may be eating almost no fat one day and need to supplement more as you go on.
  5. Don’t forget to track all of your macros. It’s not all that hard. You already know how to keep your carbs below 20 but track them anyway. Tracking the macros lets you check against the model.
  6. Don’t cut protein to accelerate weight loss. Eat protein in a consistent way. I am choosing to use Protein Powder. May not be the right choice for others. Let’s me isolate protein from the other macros.
  7. Don’t cut fat to accelerate weight loss. You will sabotage yourself by lowering your metabolic rate too far.
  8. Don’t overdo but if you overdo then make it fat that you overdo not protein or definitely not carbs. Know that too much fat slows weight loss.

Final Thoughts

The math here can be daunting. But there are calculators for every part of it on the Internet. If you don’t like the calculators you can get measured with BodPod or DEXA to get more precise body fat numbers. More precision probably doesn’t matter in most cases but if you get close to your goals it may matter.

Bottom line is:

  • Keep keto for carbs (less than 20 grams a day)
  • Eat the proper protein amount
  • Eat the amount of fat calories you need to reach your Total Energy Expenditure (minus the calories of fat your body can oxidize)

You can break your stall.