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.


Body Fat Measurement via BodPod

Well, I got the answer I was looking for. I went to the West Virginia University Human Performance Lab and had my body fat percentage measured with the BodPod.

My numbers came back as:

  • Body Fat: 25.3%
  • Current Weight: 193.3 lbs
  • Lean Body Mass: 144.4 lbs

So to get to my 15% Body fat number, I need to get to:

144 x 1.15 = 166 lbs

So I still need to lose 27 .25 lbs. I should be able to do this if I stick with the PSMF diet for the next few months.

Which Metric does it Correlate Best with?

The USN Calculator puts me at 25.0% Body fat. That’s very close to BodPod number and is much closer than both the caliper method (17%) and my body composition scale (30%).

What about Exercise Factor?

The whole idea about muscle vs fat is oversold. According to Lyle McDonald an untrained person can put on something like 2 lbs of muscle in a month. And that is for someone young, etc. But let’s assume that in 3 months I can actually put on 6 lbs of Lean Body Mass as muscle. That would put my LBM at:

144.4 + 6 = 150.6 lbs

At 15% Body Fat that would be

150.6 x 1.15 = 173.2 lbs

So there’s only a bit of leverage with the muscle. Instead of having to cut weight to 166 I could cut weight to 173.2 lbs. Either way, that’s still 20 lbs down from where I am now. And that’s the maximum amount possible.

Put another way, that 6 lbs of LBM gain results in 7.2 lbs less of fat loss needed. It does help somewhat with Base Metabolic Rate.


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.


Replacing Hi-Lyte Electrolyte

Electrolytes are important and a Low Carb diet tends to run down electrolytes. To compensate, I have been adding Hi-Lyte to my water, particularly in relation to exercise.

Hi-Lyte has the following composition in one 4.06 oz (120 mL) bottle:

Chemical mg Servings Tot g
Potassium 150 48 7.2
Sodium 125 48 6
Chloride 375 48 18
Magnesium 45 48 2.16
Zinc 3 48 0.144

The Potassium, Sodium and Chloride in the bottle are equivalent to the following measures:

  • 1 Tablespoon of NoSalt
  • 1 Tablespoon of Sea Salt

The Magnesium can easily be replaced with supplements.

The cost of this mixture is much cheaper than the Hy-Lyte ($39.99 on Amazon for three bottles).

NoSalt is $5 for 239 servings (1/4t per serving). This recipe uses 12 servings. 239/12 = 20 bottles per NoSalt container. That’s 25 cents per bottle.

Sea Salt is even cheaper at $3 for 357 servings (1/4t per serving). This recipe uses 12 servings. 357/12 = 29.75 bottle per Sea Salt container. That’s 10 cents per bottle.

So to get the Sodium, Potassium and Chloride components costs around 35 cents per bottle.


Creatine for Muscles and Diabetes

An early study (C. P. EARNEST; The effect of creatine monohydrate ingestion on anaerobic power indices, muscular strength and body composition; Acta Physiol Scand 1995, 153, 207-209) shows creatine increases workout performance.


Here’s a study on creatine loading (E. Hultman, K. Soderlund, J. A. Timmons, G. Cederblad, P. L. Greenhaff; Muscle creatine loading in men; ). My conclusion is to just do 5 g/day and don’t bother with loading.


Creatine may not be all that effective for some people (Terjung RL; American College of Sports Medicine roundtable. The physiological and health effects of oral creatine supplementation; Medicine and Science in Sports and Exercise [01 Mar 2000, 32(3):706-717]):
Cr supplementation does not increase maximal isometric strength, the rate of maximal force production, nor aerobic exercise performance. Most of the evidence has been obtained from healthy young adult male subjects with mixed athletic ability and training status. Less research information is available related to the alterations due to age and gender. Cr supplementation leads to weight gain within the first few days, likely due to water retention related to Cr uptake in the muscle.


Another study (Engelhardt M; Creatine supplementation in endurance sports; Medicine and Science in Sports and Exercise [01 Jul 1998, 30(7):1123-1129]):
RESULTS: Creatine supplementation was found to have no influence on the cardiovascular system, oxygen uptake, and blood lactate concentration. The fall in blood glucose during the exercise test was significantly reduced after consumption of creatine. Although interval power performance was significantly increased by 18%, endurance performance was not influenced. CONCLUSIONS: We conclude that creatine supplementation at doses of 6 g daily has positive effects on short-term exercise included into aerobic endurance exercise.

Good news for the kidneys (Gualano B; Creatine supplementation does not impair kidney function in type 2 diabetic patients: a randomized, double-blind, placebo-controlled, clinical trial; Eur J Appl Physiol. 2011 May;111(5):749-56. doi: 10.1007/s00421-010-1676-3)

Creatinine clearance, serum and urinary urea, electrolytes, proteinuria, and albuminuria were unchanged. CR supplementation does not affect kidney function in type 2 diabetic patients, opening a window of opportunities to explore its promising therapeutic role in this population.

Perhaps most important given the mission of this BLOG – Creatine lowers HbA1C in Diabetics (Gualano B; Creatine in type 2 diabetes: a randomized, double-blind, placebo-controlled trial; Med Sci Sports Exerc. 2011 May;43(5):770-8. doi: 10.1249/MSS.0b013e3181fcee7d.):

Twenty-five subjects were analyzed (CR: n=13; PL: n=12). HbA1c was significantly reduced in the creatine group when compared with the placebo group (CR: PRE=7.4 ± 0.7, POST=6.4 ± 0.4; PL: PRE=7.5 ± 0.6, POST=7.6 ± 0.7; P=0.004; difference=-1.1%, 95% confidence interval=-1.9% to -0.4%).


Interesting. Two things are striking about these results:
  1. Creatine dropped the HbA1C number by one full point. That’s on the order of what Metformin does.
  2. The exercise only number did not drop the HbA1C number at all. In fact, their HbA1C wen up a small amount.

n=1 – Update 2017-11-08

I took a look at my blood test from back in July and it showed:

Test Low Normal High Reference Range Units
creatinine, serum 0.77 0.76-1.27 mg/dL

So my Creatinine (produced from creatine by the muscles) number was within normal range but at the bottom of the range. This would be consistent with a Low Protein diet (I was eating less Protein at the time) and with the data above (diabetics need more dietary Creatine).

My Creatinine number from 2015 was 1.00 so there was definitely a drop in the number over the two years (from mid 2016 to the time of the test in 2017 I was definitely limiting my protein input due to my LCHF diet).

I will be curious to see if taking Creatine as a supplement along with increasing Protein and adding exercise to build more muscle mass will help in my next Creatinine test result.

Chart of Normal Blood Test Result Ranges


Hypophagia – How much fat can I lose in a day?

In the last year I have seen some ridiculous claims about weight loss. Many of them claim that people lose incredible amounts of weight in very short periods of time. And there are some times in Ketogenic dieting where you can lose a lot of weight. Particularly in the beginning when hormones are shifting due to significant drop in Insulin levels.

But I’m going to risk repeating myself and made a statement that should not be in the least bit controversial. For some reason it is controversial.

Weight loss is only vanity.
Fat loss is what really matters.

And you can quote me on that. Don’t get me wrong. If you lose body fat more than likely you will lose weight – all things being equal. But your goal should not be to be at a particular weight. Your goal should be to be at a particular body fat percentage.

How Much Fat Can a Person Lose In a Day?

Turns out this is a known quantity called the fat oxidation rate. That’s the maximum amount of fat a person can burn in a day. And the number is also know. The amount of fat a person can lose in a day under starvation conditions is 31 cal/lb/day (SS, Alpert. A limit on the energy transfer rate from the human fat store in hypophagia. J Theor Biol. 233 (1): 1–13). (Checking the numbers / units, the article states 290 kJ/kg-day, which is 69.26 kCal/kg-day. With 1 lb = 2.2 kg, that’s 31.5 kCal/lb per day).

Let me repeat myself – You can only lose 31 calories worth of fat per lb of your body fat weigh in one day. Note this is for a person who does “moderate activity”. Lyle McDonald looked at this number and concludes it’s a good starting point.

Someone else ran the numbers with more or less the same conclusions as I reach here and lays out their plan.

Suppose you weigh 200 lbs and have 25% Body Fat. Most high tech scales will give you your weight and body fat percentage. That’s 50 lbs of body fat (take the 200 and multiply it by 0.25 to get 50).

If you have 50 lbs of body fat that’s 50 times 31 calories of fat per day or 1550 calories from body fat you can lose right on that very day.

Note that the number of lbs that you can lose decreases constantly as you lose body fat.

Updated 2017-11-08: Alpert has reportedly updated his number from 31 to 22 with the following reported comments:

The value used of 31 kcal/d lb is correct only if there is no energy loss to activity. In the original paper which you cited. I took a value of activity losses from some of my previous work, but I have recently developed a much better way to estimate activity losses which changes the maximum practical value for the idealized value of maximum loss from fat alone to the actual loss to only 22 kcal/d lb. This mean that it is very hard to lose fat alone. That is life.

So What is Actually Lost in those Short Timeframes?

Water. And when things equalize in your body it returns. That’s why people say they tried a diet and regained it all back.

And there’s nothing wrong with losing the water and inflammation that goes along with water. It might make you healthier to lose some water especially if you get more mobile as a result.

But, if you look at the water percentages of healthy persons and compare them to obese persons the obese people do have much LOWER water percentages than healthy people. Here is what may be little known fact (How Much of Your Body Is Water?):

Body composition varies according to gender and fitness level because fatty tissue contains less water than lean tissue.

As you lose weight your fancy scale will tell you that you have gained a serious amount of water as a percentage. Here’s my own numbers (per my high tech scale):

  • At 248 lbs I had 69.5 lbs of water.
  • At 297 lbs I have 74.9 lbs of water.

if you do the math I have more water now than when I was 49 lbs heavier. My percentage of body that is water has gone from a very unhealthy 28% (bottom of the scale readings) to a less unhealthy 38%. Older men are supposed to be closer to 50%.

So as your weight drops your body fat percentage goes up. That’s because you really still need more or less the same amount of water in your body for blood, tissues, etc. You don’t need it in the fat cells (around 10% of a fat cell is water) but there’s some thought that the fat cells fill with water as the fat empties. Might well be the case (look up whooosh on the search box above).


Body Recomposition – Part 7

Body recomposition is the idea of replacing fat in our bodies with muscle.

Our Weight

The goal should not be weight loss. The goal should actually be fat loss.


Fat can’t be turned into muscle. They are two different types of cells and are at different places in the body.

Fat can be lost, but the only effective means to lose fat is to cause the body to eat it’s own body fat. Fat doesn’t just disappear for no reason. Your body wants to retain the fat in case it is needed.

The common way to lose weight is to reduce caloric intake and increase the energy expenditure. This is commonly called “eat less, move more”.

Fine tuning this methodology is to take a look at the macros, IE, fat, carbs and protein.

What can we do with our macros?

For body recomposition we don’t want to drop our protein levels. To build muscle mass we probably want to increase our daily protein intake. Maybe not by a lot, but it’s not the area that should be cut.

Fat and carbs both provide protein. We don’t need carbs but we do need fat. It is an essential nutrient. So this is the reason that people use low carb diets for losing weight.

Ketogenic diets are becoming popular today. They are Low Carb, High Fat and Moderate Protein. These diets provide quick weight loss but a lot of that weight is water loss. With any diet a lot of the weight loss is water. And that’s not a bad thing. But it’s quickly regained if the person returns to their previous macro mixture.

The fastest way to lose fat is to do the following:

  • Ketogenic carb levels, < 20 grams of carbs per day. This puts the diet into fat burning mode instead of carb burning mode. It’s the best way to go for people with Insulin Resistance. (Prediabetes: A high-risk state for developing diabetes)
  • Protein at a sufficient level to gain muscle mass. The amount depends upon your training level. (How Much Protein?)
  • Fat to fill the gap between what your body can provide and what your energy needs are for the day.

I’ve made a calculator to estimate these macros (PSMF Calculator).

Building Muscle

It takes physical exercise to build muscle. And the right kind of physical exercise to build muscle.

A Percentages Game

The real goal should be to drop body fat percentage. Body fat percentage is the number of lbs of total body weight that are fat. A numerical example might make the point clearer. Say a man weight 200 lbs and has 25% body fat. That man has 50 lbs of fat and 150 lbs of lean mass. If that person made a goal of 15% body fat with that same 150 lbs of lean mass that would be 22.5 lbs of body fat and a total weight of 172.5 lbs. The man’s body has definitely been recomposed even if he didn’t gain a single ounce of lean mass or muscle.

It is probably still necessary to gain muscle mass at the same time.


Nonexercise activity thermogenesis (NEAT)

There are some basic terms used in the literature.


There’s very little that can be done to affect your Basal Metabolic Rate (BMR). In fact, weight loss by definition, lowers your BMR.

If you eat less food you will have a lower level of TEF (depending on the mix of the food types). If you fast you get no TEF since you are not eating.

From (James A.Levine MD, PhD (Professor of Medicine), Non-exercise activity thermogenesis (NEAT), Best Practice & Research Clinical Endocrinology & Metabolism Volume 16, Issue 4, December 2002, Pages 679-702):

Physiological studies demonstrate, intriguingly, that NEAT is modulated with changes in energy balance; NEAT increases with overfeeding and decreases with underfeeding. Thus, NEAT could be a critical component in how we maintain our body weight and/or develop obesity or lose weight.

From (James A. Levine, Mark W. Vander Weg, James O. Hill, Robert C. Klesges, Non-Exercise Activity Thermogenesis: The Crouching Tiger Hidden Dragon of Societal Weight Gain, Arteriosclerosis, Thrombosis, and Vascular Biology. 2006;26:729-736):

Classically, there are 3 components of total daily energy expenditure (TDEE) in humans (Figure 2): basal metabolic rate (BMR), thermic effect of food (TEF), and activity thermogenesis (AT). BMR is the energy expenditure (EE) when a postabsorptive individual is laying at rest. BMR is can be measured with errors of <1% generally using a high-precision, validated, indirect calorimeter.6 In sedentary individuals, BMR accounts for ∼60% of TDEE and can be well-predicted by lean body mass (∼80% of the variance) within and across species.7,8 TEF is the increase in EE associated with the digestion, absorption, and storage of food and accounts for ∼6% to 12% of TDEE. TEF can be measured by making repeated measurements of energy expenditure after a meal, using an indirect calorimeter.6 Activity thermogenesis is typically derived by summating BMR plus TEF and subtracting this product from TDEE. Physical activity level (PAL) is frequently calculated also and is TDEE/BMR.


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.