Revisiting the “Alpert” Number

I think that the Alpert number may not be right if you are on a Low Carbohydrate diet.

The Alpert number is the maximum rate of fat oxidation from a relatively moderately active person (Hypophagia – How much fat can I lose in a day?). It occurred to me that I can check this number from my own VO2max test.

  • Looking at the REE at rest (REE from VO2max) it shows 2.16 kCal/min.
  • From my Bod Pod results (Overshot My Recomp Goals – Part 1) my fat mass is 12.3 lbs.
  • Multiplying my fat mass times the Alpert number is 381.3 kCals/day. That’s 15.88 kCal/hr or 0.26 kCal/min.

Yet, my REE was 2.1 kCal/min  at and RER of 0.73 (90% fat) which is 1.9 kCal/min from fat oxidation. Flipping the number around that’s 1.9 times 60 times 24 = 2736 kCal per day from fat.

The smallest number I saw in the resting period was 1.209 kCal/min or 1740 kCal/day. dividing 1740 number by my fat weight in lbs is 141 kCal per lb of fat mass. That’s quite a bit more than the Alpert number.

The Minnesota Starvation (Ancel Keys) data was the basis of the Alpert number. Perhaps the difference is in the idea that I am not actually in starvation? And the Minnesota Starvation subjects were fed carbohydrates in their diet.

The Alpert number pretty closely matches my own experiences in Protein Sparing dieting.

Blood Sugar and Fasting

A while back, I noticed that my Blood Sugar peaks around the second day of extended fasting. George Cahill did the seminal work measuring blood markers during starvation (Cahill, George. Fuel Metabolism in Starvation.). Here’s an interesting chart from that study that explains the sources of glucose during starvation.

This demonstrates the increase in blood sugar around day 2-3. Diabetics are particularly adept at GNG. Eventually though, even that reduces as the body becomes physiologically Insulin Resistant.

The chart can provide some idea of what happens in a ketogenic diet. Although someone on a ketogenic diet is eating enough food, their exogenous glucose is greatly reduced due to the low carbohydrate content of the diet. Glycogen stores lower next. When the glycogen stores get low the body then upregulates Glyconeogenesis (GNG).

This could also explain why when I see an increase in blood sugars on one morning I often see a drop in weight the following morning. The body is signalling that it is switching fuel to up-regulated GNG due to dropped Glycogen stores. Although these two sources are of the same magnitude in Cahill’s chart above they could well be less equally matched in a diabetic. It is possible that GNG in a diabetic outpaces the ability to pull from Glycogen stores.


Hyperinsulemia and Weight Loss

Interesting line of evidence as to why insulinemia may cause obesity (rather than the reverse). The evidence is based on a 5-6 week long water-only fast (Fasting insulin and weight loss on a water fast). In the study referenced, the fasting insulin of the individuals was measured as they progressed on the fast.

On a water fast the higher your starting weight (surrogate for “fed” fasting insulin, remote surrogate for “starvation” fasting insulin), the less weight you lose over 5-6 weeks.

Elevated insulin is associated with obesity BECAUSE it inhibits lipolysis.


Taxonomy of Low Carb Studies

I’ve been collecting studies for a while and hosting them on GitHub at OpenKeto/KetoStuff. Here’s the structure of the studies.

Some of the studies can be put into multiple places so I picked one or the other place to put them without much pattern as to why. Classifying the LC Diet as Energy Input is possibly the key insight into this pattern. Also, the Effect of the Ketogenic Diet on Diabetes is under MetS.

With GitHub Desktop you can replicate the entire repository onto your computer or select individual files to download. Copyrights are the individual holders. Studies are reproduced here and were found on the Internet in general.



Crunching Data from Cronometer

In my last post I showed how to export data from Cronometer to your favorite spreadsheet. I ran my own data and got this for totals:

Item kcal percent
Energy (kcal) 434318.19
Total Protein 155395.72 35.8%
Total Fat 259107.39 59.7%
Total Carbs 33405.04
Total Fiber 13593.28
Total Net Carbs 19815.08 4.6%

This data started at the end of October last year so it has about 7 months of complete food logs.

I have to admit I am surprised that my Protein number is that high (more than 35% of calories from Protein). But following Dr Ted Naiman’s macros that puts me at a P:NPE ratio of 1.045 which is pretty much in the middle of the maintenance range. And I have been fairly stable in weight for the past couple of months.

Here’s my weight plotted across the same time span with a red trend line. I hit a new low this AM (164.1lbs).

Here’s where it gets kinda fun. I was able to plot weight vs calories. For this I used a Pivot Table and used the sums feature to get the totals for each day.

Here I have plotted the P:NPE ratio (normalized by multiplying by 100) against my scale weight hoping to see a correlation. 100 is equal grams of protein to carbs plus fat. Numbers over 100 are more protein. Numbers under 100 are less protein.

When the blue lines are high, I was doing a PSMF cut. When the blue is around 100 I was trying for maintenance. Hard to see much of a correlation there. It could be the scale is exaggerated for the P:NPE ratio compared to the weight scale but the weight seems to be taking a fairly steady drop.

Calories in:Calories Out Meets Reality

Let’s try the same thing with calories. Surely, that will show a correlation to weight change? For this one I added the light blue trend line as a polynomial and the light green line as a poly trend line poly. Calories are scaled down to 1/10th. Clearly, when I eat 1500 calories a day I lose weight a bit faster but it’s really hard to see much of any correlation between my weight and the number of calories I eat.


Keto Podcasts

I listen to quite a few Keto Podcasts. They can be informative and in some cases entertaining. Here’s some of them.

  • The Paleo Solution Podcast – It might seem like an odd first choice but I really like Robb Wolf’s style. He’s one smart paleo cookie. He has quite a bit of keto content and has done keto for much of his adult life.
  • 2 Keto Dudes – There’s a lot to like with these two software developers turned keto dudes. They’ve had a similar journey to mine with overcoming Type 2 Diabetes and their interview format is flexible enough for them to have guests that aren’t exactly in line with their higher-fat views. I’d like to see these guys get closer to goal weight but their reluctance to do Protein Sparing Modified Fasts (PSMF) is really slowing down their progress.
  • Keto for Normies – Her voice can be grating and his can sound like a meathead but their hearts are in the right place. They aren’t afraid to try things like PSMF or Carnivore and report on their successes or failures.
  • The Primal Blueprint Podcast is hosted by Mark Sisson, author of a famous low-carb paleo blog Mark’s Daily Apple.
  • Ben Greenfield FitnessBen Greenfield is another really sharp guy with some good insights into keto and athletic performance.
  • Keto Savage – This is the guy who ate 4000 calories a day and gained body fat.
  • Keto Geek – A good science keto show.
  • Ketodontist – An orthodontist/dentist who lives keto and has some great interviews as well.
  • Keto Talk with Jimmy Moore – It is with great reluctance that I list this podcast. Mostly I am listing it because Jimmy Moore tends to have some pretty good guests. But Jimmy’s dramatics are a bit to take at times.

The same sets of guest often make the rounds on each of these shows. They all seem to have the same list of keto guests such as Dave Feldman (Cholesterol Code), Marty Kendall (Optimising Nutrition), Shawn Baker (Carnivore Diet), Ted Naiman (Burn Sugar Not Fat),  Robert Sikes (Keto Savage), Luis Villasenor/Tyler Cartwright (KetoGains). It does also entertain me that the podcasters often interview other podcasters.

I haven’t deliberately omitted any podcasts that I know of. There’s some I have not listened to yet so if I find a new one, I will add it to this list.


Weight to Height Ratio = Predictor of Mortality

From this study (Ashwell M, Mayhew L, Richardson J, Rickayzen B (2014) Waist-to-Height Ratio Is More Predictive of Years of Life Lost than Body Mass Index. PLoS ONE 9(9): e103483.

Mortality risk associated with BMI in the British HALS survey was similar to that found in US studies. However, Waist to Height Ratio (WHtR) was a better predictor of mortality risk. For the first time, Years of Life Lost (YLL) have been quantified for different values of WHtR. This has been done for both sexes separately and for three representative ages.


Objections to the Keto Diet – Part 3 – Keto diets are “unnatural”

This was my favorite criticisms of the ketogenic diet by one of the dietitians. Eating meat and vegetables is somehow unnatural. Just think how twisted that is. The truth is what is unnatural is eating processed, refined food. That’s the very definition of unnatural.

This is the central point of the Paleo/Keto movement. The diet is primal. We ate meat and vegetables for most of our genetic history. Processed/refined foods came to their place in the past 100 or less years. A mere blink in our history. Is our memory so short that we don’t know what our ancestors ate?

What About Fat?

But, let me be more generous in my response. Suppose the unnatural aspect is “eating all that fat.” Guilty as charged – the Low Carb diet does use fat as the fuel instead of carbohydrates. To someone who is ordinarily carb fueled this seems like the natural state of humans.

And, eating fat would be unnatural if nature didn’t have a mechanism in our bodies to deal with dietary fat. Fortunately, we are made to live off our body fat for long periods of food shortage. Famines were common place in our history since weather shifts and some years rains don’t come.

Genesis 12:10 Now there was a famine in the land, and Abram went down to Egypt to live there for a while because the famine was severe.

In fact, what is unnatural is food abundance. That is also fairly recent in our human history. We can live for days or weeks (months if we have enough body fat) without food. The Guiness Book record holder is Angus Barbieri who went for 382 days without food on a medically supervised fast (Longest Fast Yet – Aug 2017).

We were built to survive periods without food and consume our own body fat. We all face this every single night. Our bodies shift from burning the food we eat to burning our body fat as we sleep. When we eat we break that fast (aka breakfast). There’s nothing unnatural about this at all. If it wasn’t true we could not lose body fat.

This is a key strategy I have used to lose weight. It’s called Intermittent Fasting where I stretch out that period of fat burning by skipping breakfast. It is particularly effective since the fat we eat stays in our bodies for up to 10 hours being digested and used for fuel. After that we switch to burning stored body fat.

Overshot My Recomp Goals – Part 3

Consequences for Fasting

In Part 2, I looked at the problems with low body fat.

The first obvious consequence of being low on body fat is that I can’t do any extended fasts anymore. I really liked fasting. My longest fast was 25 days with water only. I also did four fasts of 9-10 days. And a bunch of 3-4 day fasts.

I didn’t lose a ton of weigh net from the fasts. But I did learn to not be hungry and that’s a pretty big accomplishment. I wonder if that’s part of what is happening now? Does fasting break the hunger cycles? Or is it just low carb that does that?

I probably need to evaluate doing intermittent fasts. I’ve still been eating in a window. I eat a Protein meal at 11:30, another protein meal at 3:30, do CrossFit at 5:30, then eat at 7:00 PM. That’s approximately a 16:8 fast:eat window. This gives the body time to drop glycogen stores, insulin and glucose levels.

Intermittent Fasting combined with Ketogenic (Low Carb) are a killer combination. Keto doesn’t provide insulin spikes and Intermittent Fasting lowers the Insulin level even further.

In Part 4 I take a look at Eating Strategies for gaining fat.