Protein Propaganda Pisses Me Off

There are a lot of pictures going round on various social media sites and elsewhere showing examples of 'protein-rich foods', and quite simply this pictures are outright lies! They are misleading, and real numbers provided are also wrong (sometimes by a lot), and people just assume they're true and think they can get enough protein just eating spinach. You'd have to eat ~1.75kg of spinach to get 50g of protein, I don't think anyone would actually be able to manage this but it would sure as hell be funny to watch.

Just as a note, these pictures are almost always associated with raw vegan diets, so all data is of raw, not cooked food.

Ok, lets take a look a a couple of pictures:

Some versions of this picture has a line of text at the bottom mentioning that the numbers of percentage by calorie (rather than weight), but most have this line cut off.

 Lets go to the USDA food nutrition database (http://nutritiondata.self.com) and double check these:

Food	% calories	grams/100g	grams for 50g protein
Spinach	30.1%	2.86g	1,750g
Kale	16.1%	3.3g	1,515g
Broccoli	20.2%	2.82g	1,775g
Cauliflower	18.7%	1.92g	2,605g
Mushroom (white)	36.3%	3.09g	1,620g
Parsley	19.9%	2.97g	1,685g
Cucumber	10.3%	0.65g	7,690g
Peppers	10.5%	0.86g	5,815g
Cabbage (red)	11.2%	1.43g	3,495g
Tomato	11.9%	0.88g	5,680g
Beef (composite of trimmed retail cuts, separable lean and  fat, trimmed to 1/8" fat, all grades)	34%	18.68g	270g
Chicken (skinless breast)	79.5%	21.23g	235g
Eggs (chicken)	34.6%	12.56g	400g (8 medium)

Number of plants falsely given higher high percentage of calories as protein = 9.5/10 (Only giving half a point from mushroom because the difference was small.

But percentage of calories from protein matter little, we just want to make sure we get enough protein per day. 50 grams of protein is roughly the recommended daily allowance (RDA) for a 150lbs adult (46g for female, 56g for male), it's also a nice round number which we can use to compare how much of a food we need to get the small amount of protein. As I said in my introductory paragraph, you'll need ~1.75kg (~1750g) of spinach for 50g protein. You'll also need about   5.7kg of tomato to get 50g of protein. But you only need ~270g of beef, or 235g of chicken breast. The chicken breast really pisses me off, because they claim it's low in protein (23%) when in fact of all the foods mentioned it is the highest in protein both as percentage of calories and by weight! Maybe they were using another cut of chicken but the picture shows skinless boneless breasts so that's what I data I pulled out.


 - - - - -

I want to start with my absolute scream at the computer how can anyone be this stupid point: Figs. They are 3% protein by calories, and you'd need to eat 6.7kg of them to get 50g protein. If figs are a high protein food then coconut oil is high in omega-6 fatty acids (hint it's really low!).

Ditto the avocados, only 4.2% by calories, but you'd only need to eat 2.5kg for 50g protein which'll give you 4000 calories just from avocados! Similarly goji berries are 3.6% protein by calories and you'd need to eat 7kg of them to get 50g of protein, that's more than the figs!!

Some of these foods aren't that bad really though. Hemp seeds are ~25% by calories, 135-150g for 50g protein (several data entries on CRONometer for hemp seeds (CRONometer draws from the USDA database and also has lots of brand names of health-foods)). This is likely the best protein source in the picture.

Now for a few funny ones: Brazil nuts are 8% protein by calories and you need 350g for 50g of protein, but you'll also get ~7000ug of selenium which will kill you. Chia is 12% by calories, 300g for 50g protein. But you'll have massive diarrhoea with that, as even a few tablespoons will clear you out.

Spinach, kale, and broccoli I've already covered in the last picture.

Maca: 26.7% by calories, and you need 250g for 50g protein. Not bad, but as it's a 'superfood' good luck affording it and enjoy eating a whole bag of powder in one go :P That'll also come with 150g of carb which may be high for some people.

With sprouts, it appears to be legume sprouts in the picture. Many sprouts are rich in protein because the legumes are protein-rich, but be careful as many sprouts lose protein during the sprouting process depending in species. Don't eat kidney bean sprouts raw either, they're poisonous. Mung bean sprouts, aka the bean sprouts in chinese food, are 24.6% protein by calories, but you'd need to eat ~1.6kg to get 50g of protein because they're so full of water.

I don't have data for barley grass juice, but I do for wheat grass juice: 78.7% by calories, and you need to drink ~405ml pure juice for 50g protein, have fun trying to drink all that!!

Spirulina: 54.8% protein by calories, and you need to eat 845g to get 50g of protein, which is really hard as you're eating pond-scummy bacteria.


 - - - - -

Food	% calories	grams/100g	grams for 50g protein
Almonds	12.8%	21.2g	236g
Pumpkin seeds	18.8%	30.2g	166g
Asparagus	26.5%	2.2g	2,273g
Quinoa (raw)	15.3%	14.1g	355g
Peas	23.2%	5.4g	926g
Sweet potatoes	5.1%	1.6g	3,125g
Sesame seeds	10.7%	17.7g	282g
Sunflower seeds	12.3%	20.8g	240g
Watercress	50.8%	2.3g	2,174g

Pumpkin seeds aren't that bad actually, but 166g will give you ~34g of omega-6 fatty acids too, same story with the other seeds.


 - - - - -

Legumes:

Now not mentioned in these pictures as a good protein source is legumes as they must be cooked or sprouted (we already talked about sprouting), and as we know cooked food is bad for us (not!). Cooked lentils are 26.9% protein by calories, and you need 2.8 cups (~555g) for 50g of protein (raw measure ~1cup dry, ~195g), which will also give 112g carbohydrates. Not bad for a vegan protein source.


Summary:

If you want protein, eat meat not greens. For plant based protein go for hemp seeds and cooked legumes like lentils and kidney beans.


Musings:

When a vegan points out that a cow can grow big on a vegan diet, point out the high protein content of wheat grass, but they also eat all day every day to digest it and need four stomach and multiple chewings to digest it. Gorillas also eat high-protein leaves too and also spend a lot of time eating a lot of food, have huge caecums, and eat their poop for vitamin B12 (go search youtube, there are thousands of videos capturing different apes doing this). Also these animals are actually eating a ketogenic diet as the huge amounts of fibre eaten are fermented into short chain fatty acids such as butyric acid (named for being in butter) which they get ~65% or more of their calories from (more for cows as fermentation is earlier)! (link) If you really want to eat like a herbivore, grow/buy ~3kg of watercress daily and ferment it until it's nice and rich in butyric acid then drink/eat the resulting concoction. Mmm, gross, that's why real herbivores ferment in their guts... which we're not able to do. Now grow a pair and eat your damn steak!


References:
1
http://www.facebook.com/photo.php?fbid=395100227225462
http://www.facebook.com/photo.php?fbid=524174750943005
2
http://www.facebook.com/photo.php?fbid=534121186613769
3
https://www.facebook.com/photo.php?fbid=363770357056467

Note:
If my numbers are wrong at all, please let me know and I will correct this article. I'd rather say I was wrong then continue to spread lies, unlike some people.

Calcium

Sources other than dairy:

Small bones: fish (sardines, etc), eaten with the fish or as broth.
Big bones: beef/lamb/pork/chicken/etc, as broth.
Eggshells, as broth.
Green leafy vegetables: darker the better, cook well and eat with fat. Avoid greens high in oxalic acid though, such as spinach, beets, celery, pecans, tea, and cocoa. (Although these aren't eaten on a carnivorous diet)


Maximising calcium:

Absorption		Excretion
Increases	Decreases	Increases	Decreases
Viamin D	Phytic & oxalic acids	Fibre	Potassium
Animal Protein	Caffeine		Boron (-44%!)
Phosphatase**	High cortisol (metabolic stress)
	Magnesium*
	Phosphorus*
Vitamin K2 to get it into bones and not into arteries.

* Although magnesium and phosphorus help calcium balance it should not be eaten/taken at the same time as calcium as they can compete for absorption.

** Phosphatase is an enzyme in raw milk, it is destroyed when milk is pasteurised (in fact they test that this enzyme is dead to confirm it’s pasteurised). This is why most studies show milk doesn’t help bone health: they used pasteurised milk! If you want to drink milk, drink it unpasteurised.


Some other nutrients that help are copper (found in liver), iodine (seaweed, seafood), vitamin A (liver, egg yolks, dairy fats), silicon (bones, dark green leafy veg, certain spring waters), strontium (dairy, shellfish), sodium (salt), CoQ10 (heart), vitamin B5 (liver, egg yolks, dairy), boron (I can't find any good animal food sources of this), zinc (red meat), and manganese (tea/spices).

Nutrients that hinder include sugar (refined and natural), lead, cadmium, fluoride and excess phosphorus (see note above).


Weston A Price on how much calcium/phosphorus we need:

• 680mg Calcium
• 1,300mg Phosphorus

Factoring in our absorption increases from lack of phytic acid this actually comes out as needing ~544mg calcium (just over half an egg shell's worth). Regarding phosphorus, at lot of that phosphorus on a WAPF diet is locked up in phytic acid so much less is needed on a phytic acid free diet.


Bones:

Bones have lots of phosphorus, as bones are made from hydroxylapatite [Ca5(PO4)3(OH)] and some calcium carbonate. Together these make up 65% of bones, water 25%, and the remaining 10% is formed by magnesium, sodium, potassium, sulphate, and other trace minerals. This means that bones are ~10% calcium and 6% phosphorus by weight (~1.7 Ca:P ratio). As a diet of pure muscle meat has little to no calcium (unless using ground meat due to trace amounts of bone in it), adding ~600mg calcium worth of broth will actually add about ~360mg of phosphorus too, and my upcoming second version of the perfect carnivore diet menu has about ~940mg of phosphorus (and ~160mg calcium), so adding broth rather than egg shells (as used in version 1) will ~1300mg phosphorus and ~760mg calcium which is in line with the WAPF recommendations.


Breast Milk:

Breast milk contains ~320mg calcium per litre, and this is about how much an infant drinks. Not very much at all considering how fast they're growing and calcifying their bones. We can probably safely assume that an adult is unlikely to need more calcium than a growing infant, even though some calcium will be needed for bone turnover, replaces trace loss in urine, etc.

It's interesting the RDA for calcium under a year old is only 200-260mg, and jumps to 700mg at one year then 1,300mg after 4 years. Although I can't find the source at the moment, I remember reading a study looking at primitive cultures, their calcium intake and their fracture rates, many got only 200-300mg of calcium and had very little fractures, no culture ate under 200mg. This all points to us not actually needing very much calcium at all really, and rather needing more of calcium's co-factors for healthy bones.

The importance of vitamin K2:

Many people know of vitamin K1, found in dark green leafy vegetables. Vitamin K2 can be made from K1 but only in small amounts (similar to our poor beta-carotene to retinol conversion). Vitamin K1 helps blood clotting (recent studies show K2 mk-4 can do this too), but vitamin K2 has many other jobs: Vitamin D helps you absorb calcium, but vitamin K2 gets it into the bones. Without vitamin K2, absorbed calcium tends to end up in your arteries causing heart disease! Never take a calcium supplement unless you take plenty of vitamin K2 with it.

Vitamin K2 found in fermented plant foods, like natto and sauerkraut, is a different form than found in animal foods (‘Mk-4’ in animal foods, ‘mk-7’ in fermented plants). When a plant rich in vitamin K1 is fermented, bacteria turn some of it into K2 mk-7. Mk-7 doesn’t get absorbed into body tissues well so can build up in the blood. This mk-7 is actually slowly broken down into the animal form mk-4, think of it like a slow release form.

The reason K2 mk-4 is found in animal foods is because that’s the form animal made from K1. Grass-fed animal fats are rich in K2 mk-4 because their food has loads of vitamin K1 and their digestive systems are great at converting K1 to K2 (unlike ours). Any food that concentrates healthy animal fats is rich in K2 mk-4. Examples include cheese (awesome calcium + K2 combo), liver (that’s where the body stores it; foie gras (fatty goose liver) has huge amounts), and egg yolks have lots for the growing chick.

Links on k2:
http://blog.trackyourplaque.com/2007/12/food-sources-of-vitamin-k2.html
http://www.springboard4health.com/notebook/v_k2.html
http://www.drpasswater.com/nutrition_library/Schurgers2.html (research with graphs)


My recommendations:

Get at least 200-300mg calcium every day, which is about a quarter of an egg shell's worth. Make sure you eat plenty of animal protein and fats, avoid anti-nutrients, eat some liver (for the copper!), egg yolks, seafood/weed, and salt (sodium and potassium) too for the co-factors (as listed above), and drink unfluoridated water preferably one high in silicon.

At a very minimal zero carb diet, I would say to make sure you're getting more calcium than steak provides (0mg), at least eat ground meat which has traces of bone in it (1lb 30% fat ground beef has ~108mg calcium) and drink some broth or make egg shell calcium (2 shells a week provides ~285mg calcium a day).

How little vitamin A is enough?

There have been many discussions between me and the zero carb community as to how much vitamin A is needed to avoid deficiency, they maintain that fatty muscle meat has enough to prevent deficiency and that extra source such as egg yolks, dairy fat, or the dreaded liver aren't needed. I could not find data showing the amount of vitamin A in beef, most nutritional databases have is zero. But as promised I continued my search into why many do not seem to be becoming deficient in this nutrient...

In human tissue, there is some retinol (vitamin A) present in the fatty tissue, muscle, and heart: fatty tissue contains on average 1.46ug/gm, muscle 0.35ug/gm, and heart 1.08ug/gm [source, table 1 page 253]. Assuming beef is about the same (not condoning cannibalism here :P ), a diet of 500g lean muscle meat and 200g fat (for 100g protein and 200g fat, ~2000 calories ~80% from fat) would give us ~467ug of retinol (~1556.5IU).

The USDA RDA for vitamin A is 900ug or 3000IU, which is about double our calculations; assuming increased absorption from plenty of fat and lack of anti-nutrients, this may well be enough to prevent deficiency. The paper also investigates blood plasma retinol levels and concludes that 1,200ug retinol is needed to maintain a healthy blood level, and under 600ug a day is when eye changes start to occur [page 273-274]. Again assuming increased absorption on a carnivore diet, fatty muscle meat way well be enough to prevent deficiency, but may not be enough to maintain a more desirable blood level.

For comparison, the amount of vitamin A in our calculations above can be found in 55g of cheese or 20g of butter or two eggs. So adding any of these to your diet would mean you reach the USDA RDA. To get the 1,200ug retinol that the article recommends you need to eat ~5,100 calories of meat, or just 2,000 calories of meat plus 15g of beef liver a day (or 10g lamb liver).


A whole cow will generally give 442lbs of bonless meat, 27lbs shanks/oxtail, 6lbs liver, 2lbs heart, and 2lbs tongue. This means that eating the whole animal you'd eat a pound of liver every 40 days if eating 2lbs. This is roughly similar to the Bear eating liver once a month. The cheese in his diet would have also provided some vitamin A/retinol. As I don't have the exact make up of his diet (other than him mentioning eating liver about once a month) I can't work out exactly how much vitamin A he was getting over the years but he was roughly eating liver in proportion to meat as found in a whole cow which is a very good strategy. A pound of beef liver every 40 days (~11g per day) gives us on average ~561ug retinol (~1876IU) a day, making the total in addition to the meat above 1,028ug (3,432.5IU) a day, above the USDA RDA and almost to the article's recommended 1,200ug retinol; so with some cheese we can easily reach this target.

A diet of meat, daily cheese, and liver every 40 days would quite likely be enough to even maintain optimal blood retinol levels, while a diet of just fatty muscle may be enough to just avoid deficiency.


So while fatty muscle meat may be enough to prevent deficiency, I still maintain that there is a difference between outright deficiency and optimum nutrition and will be sticking with the WAPF's recommendation for vitamin A in my carnivore RDA project, which is 10,000IU. This means including egg yolks, dairy fats, and of course occasionally the dreaded liver.

Fat Soluble Nutrients

Vitamin A:
The best source of knowledge on vitamin A seems to be the Weston A Price Foundation, which recommends at least 10,000IU for all adults (double that for pregnant/lactating women, half that for children <12 years old). This is much more than the USDA's upper limit, but so is the amount of saturated fat and cholesterol in this diet :P But if one is only getting the USDA RDA then it's likely to be enough to avoid strict deficiency, but not optimum.

Update on how little vitamin A is enough.


Vitamin D:
Actually a hormone and not really a nutrient. We get most of our need for this of from the sun, but some people can be deficient. It's best to get a blood test and supplement based on your levels. The Vitamin D Council recommends everyone take 1,000IU per 25lbs body weight (6kIU per 150lbs) and that the ideal level is ~50ng/ml or 145nmol/l. I took 5,000IU at more than 150lbs, and after a year had levels tested and result simply said '>200nmol/l' so clearly this to too much for me. Always go off your blood levels, not a specific IU recommendation!


Vitamin E:
Dr Udo says in his book "Fats that Heal Fats that Kill" that we need 0.65mg(?IU?) of vitamin E per gram of PUFA. This is a much better start for establishing a proper RDA for vitamin E compared to a flat 15mg RDA.

My diet version 2 gives 70% of that. As Udo is dealing with refined seed oils then the need of vitamin E is quite likely to be higher than with animal fats as saturated fats protect PUFAs from being oxidised. Udo's oil is 12.8/20.4/66.8% sat/mono/pufa with a omega-6:3 ratio of 0.44, while my diet is 47.3/47.6/5.1% and has a ratio of 2.3; as my diet has 3.7 times the saturated fat so the amount of vitamin E needed per PUFA may be as little as ~0.18mg/g. Using PUFA as a basis, my diet has ~7.6% the PUFA as his oil so this would mean vitamin E need is ~0.05mg/g PUFA.

Additionally the increased levels of glutathione (the most potent antioxidant in our body) on a carnivore diet due to increased intakes of cysteine, methinoine, and glycine (from meat, eggs, and gelatin respectively), means that the PUFA will be less prone to oxidation once in our blood. Some vitamin E or saturated will still be needed to prevent oxidation during storage and cooking though, but I'm perfectly happy that the vitamin E requirement is so low it's not worth worrying about as there are so many other protective systems in place.


Vitamin K1:

One major issue with a carnivore diet is lack of plants containing vitamin K1, animals foods contain no K1. Vitamin K1 is needed for coagulation, or is it? This study suggests that K2 can provide this function of K1, making K1 requirement nil in a carnivore diet providing plenty of K2.


Vitamin K2:

Vitamin K2 can be synthesised by healthy gut bacterai but they need K1 as a starting point sadly. OTher sources include fats, especially dairy fats, grass-fed fats and feremented fats. I'm having a lot of toruble finding the specific amount of K2 needed but that may be because it's a very new vitamin and so little is known about it. Assuming the K1 requirement should be replaced wholely by K2, then this means ~80ug for adult, 150ug for eldery people.

Where can be find that much?
105g hard cheese a day will give you 80ug, 533g butter (grass-fed is better) or a similar amount of egg yolks, pastured egg yolks are better needing only ~249g. (source) The WAPF recommends taking high-vitamin butter oil which is a natural concentration of vitamin K2, but that it's not needed if one if eating a lot of grass-fed fats.

Supplementing:
Taking 1mg every 2 weeks gives an average of ~71ug per day, which in addition to the fats and egg yolks in the diet will provide ample amounts. But this is very unlikely to be needed because of the increased absorption from a high-fat anti-nutrient-free diet.

I would say not to worry about vitamin K2 though due to increased absorption  but our knowledge on this vitamin is severely lacking. Watch this space, as they say.

If you have osteoporosis or arterial calcification then supplementing is advised  up to 5mg a day may be needed in extreme cases if a VLC/ZC ketogenic diet doesn't help.


Caveat:
The WAPF warns not to take vitamin A without vitamin D, and not to take vitamin D without K2. So if you're deficient in vitamin D, don't eat liver just yet, and make sure to always eat plenty of animal fats, preferably grass-fed or cheese.

Further Implications of Lowered Gluconeogenesis: Vitamin C Synthesis

This is a follow up post to "Evolutionary Trade-Offs: Fast Versus Famine" and "Detox, Antioxidants, and Scurvy: Protein Beats Plants".

We already looked at how we manage without the ability to synthesise ascorbic acid aka vitamin C, by using uric acid derived from protein instead, but why do we do this? Why not just make vitamin C like other carnivores do? Indeed all carnivores make ascorbic acid, so why are we different?

I believe that our lower level of gluconeogenesis (GNG) is to blame. Ascorbic acid is synthesised from glucose, and with a diminished capacity to make glucose then we don't really have any spare, the muscles need all they can get. So to converse the precious small glucose pool we switched from using ascorbic acid (derived from glucose) to uric acid (derived from protein), and one big difference is the amount of the substance needed for the same anti-oxidant potential.

Most animals synthesise tens to hundreds of grams (not milligrams  of ascorbic acid daily, where-as in humans if we supplement 10 or more grams we can experience diarrhoea from too much vitamin C (less on a ketogenic diet). It's almost as if the body doesn't want extra vitamin C, and high levels can only be achieved through IVs. Amounts over 1.5mg/dL (or 1.3mgdL in females) is rapidly excreted through the urine (this is about 75mg (or 65mg in females)  in the whole blood) with a half life of about 15 minutes, this is less than the USDA RDA at 90mg (75mg for females)! The body is actually very good at maintaining tight levels of ascorbic acid in the blood, and the daily turn-over on a vitamin C free diet (but grain-rich) can be as little as 2.5mg, so perhaps even less on a ketogenic diet.

Where-as the amount of uric acid in the blood ranges from 3mg/dL to 7mg/dL in males and 3mg/dL to 6mg/dL in females (150-350mg or 150-300mg in the whole blood). Also although 'hyperuricaemia' (high uric acid levels) is set at 6 or 7 mg/dL, some people can have as high as 9.6mg/dL and not develop gout. Vegetarians can have as little as 2.7mg/dL uric acid.

So a normal uric acid level is two to ~4.5 times as much as the saturation level of ascorbic acid!

Not only do we not make ascorbic acid (because of lowered GNG) but the blood has very low saturation levels compared to uric acid and excess is rapidly excreted, excess uric acid is less easily excreted suggesting a preference for higher levels. This further supports by theory that uric acid replaced ascorbic acid in humans.

Evolutionary Trade-Offs: Fast Versus Famine

This is a sister post to Primal North's "Keto Adaptation vs Low Carb Limbo".



Gluconeogenesis (GNG) is a big topic in ketogenic dieting, and most people think it means eating too much protein knocks you out of ketosis as they think excess protein increases GNG which then increases blood glucose and thus insulin. This is completely wrong. GNG changes little between a high-carb and low-carb diet (link), which of course means Jaminet's idea of eating 'safe starches' to "less the burden on the liver" is nonsense, but it actually has many implications that no-one seems to be addressing: glycogen depletion from exercise in keto-adapted individuals. To many the mere idea of glycogen being using when keto-adapted, let alone it being depleted, is seer heresy but it can and does happen, and a lot more often than people think it does.

We have three major fuel tanks, as it were, in our body: glycogen, fatty acids, and ketones. We burn a mix of these at all times. There are three basic 'modes' that our body uses:

• Carb mode: most energy is being derived from glycogen, and a small amount from fatty acids.
• Fat mode: most of the energy comes from fatty acids, and of the rest most comes from glycogen, and a small amount from ketones.
• Ketone mode: about half of the energy comes from fatty acids still, but of the rest most comes from ketones and a small amount from glycogen.

We burn glycogen all the time, whether we eat high-carb, low-carb, ketogenic, zero carb, nutritional ketosis; it doesn't matter what diet you eat, we always burn some glycogen. While exercising energy requirement increases and so too does need for glycogen.

The reason I describe them as 'modes' is because the body doesn't slowly change what fuel mix it uses, it's like a switch, the body will suddenly change from say fat mode to ketone mode. This study (link) on sled dogs revealed that "[d]uring the first few days of racing, sled dogs draw energy from glycogen stored inside muscle cells. But instead of depleting glycogen stores and tiring the muscles, the animals suddenly switch to a glycogen-sparing metabolism." (Emphasis mine)

But what's interesting is that after racing 100 miles for 5 days, their muscle glycogen was slightly higher than when they started (link). Even if they're burning a smaller amount of glycogen something has to be refilling it for it to end up higher. Most people think GNG means turning protein into glucose that then raises your blood sugar, this is wrong, GNG is the turning of protein into glycogen. All carnivorous animals have high levels of GNG in their liver, and they need it to be high, as they need glucose to simply live (all animals die if blood glucose levels drop to 0) but also to fuel their high intensity exercise aka chasing down prey.

Dogs and cats, which are domestic versions of wild wolves and big cats, have much higher levels of GNG in their liver, and only can tolerate higher levels of protein intake than us before toxicity aka rabbit starvation. The sled dogs in this study ate a lot of protein: "[e]ach 50-pound canine consumes about 12,000 calories daily (typically 60 percent fat and 40 percent carbohydrate and protein)", this works out to 800g of fat, and up to 1200g of protein and this is for an animal a third our size!

The reason these animals can tolerate a much larger amount of protein then we can (anything over ~200g of protein for a human starts to become toxic), is because they have a higher level of GNG. Dietary protein has three major metabolic pathways it can take: muscle/protein synthesis, GNG, and breakdown to urea. Only so much goes into muscle/protein synthesis, as much is needed but only so much proteins are needed and even rapid muscle growth works out to only a handful of grams a day; the rest either gets turned into glycogen via GNG, or is broken down in urea and then excreted in our urine. So when certain leaders of certain zero carb groups say that excess protein isn't a problem at all and won't raise blood sugars and drive up GNG, they're partly correct. GNG is limited by the size of our liver, and doesn't change much depending on diet, the excess protein is indeed broken down in urea and excreted as they say. But we also have a limited capacity to excrete urea and excess protein leads to a build up of urea in the blood which is the mechanism by which we get protein toxicity aka rabbit starvation.

Why is the level of GNG important? Because it limits our ability to refuel glycogen when we don't eat carbs (or not enough). If our glycogen fuel tank becomes empty, doesn't matter what 'mode' we're in, then we will 'bonk out', 'hit the wall', call it what you want but it means you're not going to finish that race, if keto-adapted you may be able to struggle through it. Once the glycogen tank is empty, it can take a long time to refill it and during this time many of the common effects of low carb limbo are seen such as hypoglycaemia and increased risk of infection. Our ability to refill glycogen limits our exercise capacity, in animals such as dogs they can eat huge amounts of protein which undergoes GNG and refills that glycogen such that they can have more glycogen after 500 miles than before they started. In tests on humans running while consuming low-carb diets, we see that glycogen is depleted during exercise, and while it is depleted much slower than someone eating a high-carb diet, it needs to be refuelled between exercises. But because GNG is governed by our livers, and eating more protein doesn't increase it, this means that we can only refill so much of our glycogen tank before we have to exercise again. So while a sled dog can refill that glycogen tank completely say overnight, we need longer than that to get our glycogen back up.

So if one is only eating no/little carbs, they need to ensure that there is adequate time between heavy exercises such that our glycogen can be refilled sufficiently. Repeated heavy exercise too close together results not only in 'bonking out' but even illness. My good friend Danny Albers of Primal North has experienced this first hand, if he doesn't 'carb back-load  (to refill glycogen), consume 'superstarch' (more on that later), or wait long enough between exercising, he gets a cold or infection, sometimes very bad.

So then how do people like Jimmy Moore avoid this? Because Jimmy Moore measures his blood ketones, and Danny doesn't. Jimmy Moore reports that if his blood ketones are over 1.5mmol/L then he can exercise fine, if it's lower then he will bonk out (link) and instead chooses not to exercise that day. Your blood ketones need to reach a certain level for you to be in ketone mode, aka keto-adapted, below this level you are only in fat mode and will still be burning quite a lot of glycogen.Jimmy's diet is 85% fat, 30g carbs, the rest protein, but even he isn't in ketone mode all the time and must measure his blood ketones before exercising. If you aren't measuring your blood ketones before you exercise then you have no way of telling if you're keto-adapted or not, blood ketones mean nothing. Take the time to read Danny's brilliant post on what true keto-adaptation is (link). Everyone will have a different level of blood ketones at which they will switch to ketone mode though, so you will need to test each time and not at which level you don't bonk. Those who have never been obese, and have been on VLC/ZC diets for a very long time, will have a lower threshold for keto-adaptation, this applies to us and animals (in the zero carb community they actually stress not exercising for 6 months, likely in part to attain this ideal before you do). The wolf who has eaten a carnivorous diet his whole life will be able to access that ketone mode much easier than a previously morbidly obese person with metabolic syndrome, as evidenced that the sled dogs switched to ketone mode only after a couple days of running, while it can take somebody months and months to keto-adapt.

But even those who have been eating a zero carb diet for a very long time, and have never been obese will find there is a limit to how much they can exercise because of this lower GNG level compared to other carnivorous animals; a certain leader of a certain zero carb group only runs half marathons and finds he bonks out if he attempts to run a full marathon. But wait, I hear you cry, what about that guy who set a new world record in the Western States 100, wasn't he low carb? (link) Yes he was, but he consumed about 2,000 calories worth of glucose over the course of the race, AND he was taking a bee pollen supplement that enhances fatty acid oxidation. 2,000 calories of glucose may sound a lot, but compared to the roughly 10,000 calories needed to run the race it's actually quite small (the high-carb runners have to consume 10,000 calories of glucose over the race minus what they can carbo-load the night before), the rest of coming from fatty acids and ketones. So even he had to refill that glycogen or risk bonking, but he needed much much less as he was burning it at a slower rate and using mostly his own body fat for fuel (as a mix of fatty acids and ketones).

So why do we have a lower level of GNG, especially if we're meant to be pure carnivores as some claim? Well let's take a look at cats, cats have the highest level of GNG in the animal kingdom and thus the highest dietary protein requirements. What's really interesting is if you fast a house cat for more than a day or so, it can develop fatal fatty liver as it starts to burn it's own muscle tissue for GNG. So if you're an animal with a very high level of GNG, you can't fast even for a few days, but you can refill the glycogen that's used up in heavy exercise hunting down prey to ensure you're not fasting. But instead if you're a carnivore with a low level of GNG then you may not be able to run marathons every day such as to hunt prey, but you can happily survive those periods in between hunts, even if they're weeks apart, such as if they're not much prey.

Our lower level of GNG compared to other carnivorous animals is an adaptation to famine!

So we have an evolutionary trade-off, while other animals such as cats are adapted for hunting more frequently and faster (just look at a cheetah!), we humans selected for famine over fast.

So what do we do if you want/need to do heavy exercise more frequently than can be supplied by GNG? Here are the options:

• Backload carbs: refill the glycogen after exercising.
• Cycle carbs: eat high-carb on workout days and low-carb on rest days, or carb-up once a week.

But what if you don't want to or can't eat carbs for whatever reason? There may be a couple ways to 'cheat'...

Talking to many zero-carbers it seems that animal based carbs (such as from dairy or shellfish) don't raise their blood sugar as the same amount of carbs from plants would. Are animal carbs somehow different from plant carbs? They may well be, in chapter 9 of "How To Prevent Heart Attacks" by Ben Sandler (link) he talks about something called 'gamma-glucose'. The basic idea is that there is a third kind of glucose (normal glucose comes in two kinds, alpha and beta) which is different, it's unstable and made by the liver. When we eat carbs or otherwise increase insulin then we make less 'gamma-glucose', and increase our production of 'gamma-glucose' after a meal with only protein and/or fat. So carbs from animal sources may be in the form of this 'gamma-glucose' and so animal carbs may be good for refilling glycogen without triggering insulin production.

Another 'cheat' is super starch (said I'd get to it). Super starch is a special kind of carbohydrate that is designed to refill glycogen without increasing blood glucose or insulin. Many athletes use it because it's doesn't upset the stomach like other carbs (the main reason ultra-marathoners are turning to low-carb is because the frequent carb-ups over the course of the race upset the stomach to the point where it won't except any more and they simply throw everything up, then run out of glycogen and bonk). Volek, of The Art And Science Of Low-Carb Living/Performance has written several articles/papers on super starch (link). Peter Attia uses super starch to help him exercise efficiently (link and link). My good friend Danny Albers has personally tried out a similar product to super starch (again designed to refill glycogen without increasing glucose/insulin, just cheaper) with great results in his exercise (link).

Homocysteine and Glutathione Nutrients

Folate, choline, B6, and B12

All these nutrients are part of the homocysteine cycle. High blood levels of homocysteine are dangerous and greatly increase your risk of heart disease. Homocysteine can be recycled to methionine by several routes: by choline; or folate. It can also be excreted as uria after being converted to cysteine by vitamin B6.

Here are a couple of pictures of the homocysteine cycle, showing how the nutrients interact (choline is listed as it's active form 'betaine'):

Elevated homocysteine is usually treated with a low-methionine diet with limited results, just like a low cholesterol diet doesn't reduce cholesterol levels. Also as methionine is found in many nutritious foods, such as eggs and other animal foods, restricting it can lead to an unbalanced diet. Increasing choline, folate, vitamins B6 and B12 is much more effective at reducing homocysteine levels, though some are more effective than others, as we will see...


Folate versus choline: Spina Bifida

Many women eating carnivorous diets, low in folate as little to no chicken liver was eaten, have produced healthy babies free of Spina Bifida. Normally women are given folic acid supplements in early pregnancy to prevent this disease, ignoring the folate versus folic acid issue for now, if folate/folic acid is so important for preventing Spina bifida, how can healthy babies be born to a mother eating a diet very low in folate? My thoery is that choline replaces most if not all of folate's duties, as it's not folate itself but high homocysteine and low glutathione that is the real cause behind folate deficiency problems such as spina bifida.

Seems others agree: "Anomalies in homocysteine metabolism have been implicated in disorders ranging from vascular disease to neural tube birth defects such as spina bifida." (link)

Homocysteine is an amino acid derivative in the blood, high levels are associated with heart disease. The usual method for reducing it is restricting methionine as it's made from that, but this doesn't really work just like restricting cholesterol intake doesn't help blood cholesterol levels. Folate can be used to reduce homocysteine blood levels by recycling it back into methionine, and so can choline.

Folate needs B12 in order to recycle homocysteine, a normal mixed diet has very little B12 compared to a carnivore one which is why such large amounts of folate are used in supplements to prevent Spina Bifida, as much as 5mg (5,000ug) or more. The increased B12 on a carnivore diet means less folate is needed to effectively recycle homocysteine.

Similarly choline needs zinc. My menu provides ~23mg zinc, while the USDA RDA is 11mg, so it's likely less choline is needed also. Choline has many other functions though, making phospholipids and other things vital for brain development, and helps in metabolising fats so it's unlikely a lot less is needed on a carnivore diet.


Another Way Out

Apart from recycling homocysteine back into methionine, we can exit this cycle using B6, and it turns into cysteine. Add some glycine (gelatin), and glutamate (any protein) along with selenium, and they make glutathione, the body's most potent antioxidant.

In trials with homocysteinuria, a genetic disease which presents with very high levels of homocysteine and heart disease, homocysteine is successfully lowered with folate but the heart disease rate stays the same, but giving vitamin B6 instead does help the heart disease! This shows that recycling homocysteine back to methionine is of little value, to proper thing to do is turn it to cysteine, then glutathione.

I think it's not the high homocysteine itself causing the problems but the low glutathione levels. Low glutathione levels are the reason why the low protein rats in Colin T Campbell's studies just all died instead of getting cancer (link).

The WAPF reports that 3.4mg of B6 daily is needed to fully saturate B6 levels in breast milk (link), so for pregnancy I will assume a similar level is needed, and less while not pregnant. Using the ol' 'eating for two' would mean 1.7mg B6 is needed; the USDA RDA is 1.3mg normally, 1.9mg for pregnant, and 2mg for breastfeeding, proportionally if breastfeeding really needs 3.4 then normal means ~2.2mg is needed. Vitamin B6 recommendations used to be based of protein, to the tune of 0.016mg per gram of protein intake, so 1.6mg per 100g of protein. I would err on the side of caution and say that more B6 is likely better, but if there is sufficient cysteine, glycine, glutamate, and selenium in one's diet to make glutathione without needing B6/homocysteine then glutathione levels will still be high, and B6 is not as critical.

Thus I will no longer be recommending chicken liver specifically for it's folate content, and am happy that the amount of folate provided by the other liver and egg yolks is plenty (1 egg has as much folate as 2000 calories of rib eye), these foods also provide choline for alternative recycling of homocysteine.

The carnivore RDA will have a lower recommendation for folate than the USDA RDA, choline will be same or greater than USDA RDA, zinc will remain at 12x copper but likely more copper will be recommended than the USDA RDA, and B6 will be based on protein intake. There will also be emphasise on getting plenty of vitamin B12, selenium, methionine, cysteine, and glycine.

- - - - - - - - - -

Side Note: Folic acid versus Folate

Folic acid is the artificial form of folate, found only in supplements and added to foods such as flour. Folate is the natural form found in food. An enzyme called dihydrofolate reductase is needed to convert folic acid to folate, this enzyme is also needed to convert folate to it's active form tetrahydrofolate (THF); too much folic acid slows the synthesis of THF and can actually cause deficiency.

Conversion of folic acid to folate is low but variable (link), and excess unconverted folic acid is dangerous (link). Two genes that effect dihydrofolate reductase are: C677T and A1298C. Having these mutations decreases your ability to convert folic acid to folate.

Too much folic acid is also associated with caner, high serum levels are associated with epigenetic changes linked to bowel cancer (link), and cell grown in cultures with high levels of folic acid induces these changes. Selenium and vitamin D3 levels decreased these changes, all the more reason to eat your kidney or pork and soak up the sun. But it seems natural folate is anti-cancer: "daily supplementation of 1 mg of folic acid increased the risk of prostate cancer, while dietary and plasma folate levels among vitamin nonusers actually decreased the risk of prostate cancer" (link). Anti-folate drugs are used as a treatment for cancer (link). More info.

For these reasons I recommend getting natural folate from food rather than supplements as folic acid.

If you must take supplements, seek out one of the following, as these are true folate rather than folic acid: 5-MTHF, 5-methyltetrahydrofolic acid, l-methylfolate, levomefolic acid, folinic acid, 'Metafolin', 'Deplin', 'Quatrafolic'.

Side Note: Alternatives

The folate cycle also turns a serine into a glycine, serine is an amino acid found in egg yolks, pork liver, turkey, and to a lesser degree other livers and muscle meat, so if a large amount of folate is eaten then less glycine from gelatin is needed; so the choice is between eating gelatin or poultry liver. One or the other is needed, as glycine is a critical component of glutathione.

I don't know if high amounts of choline mean that folate isn't used to recycle homocysteine, and thus less glycine is made, so I do feel it's much less risky to eat gelatin for the glycine directly.