Mean values from 12 infants (age 11 days-12 months) were: CBF 69 ml/100 g0min-1; cerebral uptake (in mumoles/100 g-min-1): oxygen 104, glucose 27, acetoacetate 0.9, D-beta-hydroxybutyrate 2.3; cerebral release: lactate 2.4 and pyruvate 0.8. Significant uptake of amino acids was found only for histidine 0.95 and arginine 0.7. Significant correlations between arterial concentration and cerebral exchange were found for: ornithine, arginine, phenylalanine, aspartic acid, serine, glutamine and acetoacetate. CBF and substrate exchange were unrelated to age within the group.
Infants had higher mean CBF and greater uptake of ketone bodies than has been reported in adults.
There’s an interesting book which describes the capture of frontier folks by American Indians in the frontier era. Often these captives were adopted by their Indian captors to replace family members who had died. In some cases, the captives later refused to return to European American communities when they had the opportunity. There’s a book which collects together many of their experiences (Captured by the Indians: 15 Firsthand Accounts, 1750-1870. Edited by Frederick Drimmer, 1961).
Diet Was Animal-based
The book recounts the diet of the North American Indians and the adaptation of people who were on European diets to the diets of the Indians. The Indians relied largely on animals for their food.
Differences from European Diet
The European captives seem to have suffered the equivalent of the ketogenic flu when they adapted to the Indian diet. They describe a couple of rough days at the start when they abruptly ceased to eat the European diet.
There were definite differences in diet. For example, the Europeans were used to bread at all of their meals but the Indians ate meat alone. From p 27.
This is as simple as the idea that the Indians were largely nomadic in the summer. They built shelters in the winter and stayed at those locations.
Other food they ate included:
boiled venison (p. 33)
buffalo (p. 34)
deer, bear, racoon (p. 38)
wildcat (p. 40)
fox (p. 41)
hickory nuts (p. 37)
hawthorn seeds (p. 37)
green corn (pp. 33, 41)
There are some very specific details such as this account of cooking a bear (p. 39).
For carbohydrates the women among the Indians tapped trees for sap and then concentrated the sap by heating it in bronze pots. They would dip their meat in the syrup. Here is the account of how they made syrup.
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.
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.
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.
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.
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:
Total Net Carbs
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.
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 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.