Home-made Mineral Water

Most water is pitiful, it's either contaminated with chlorine/fluorine, or is very poor in minerals after being cleaned/filtered. Here I purpose the ultimate solution (pun intended), for home-made mineral water.

Recipe:

• ~2L distilled or very pure water
• ~200mg silicia
• ~150mg magnesium citrate
• 1/2tsp sea salt, eg himalayan pink salt
• 1/2tsp low-sodium salt (66% KCl)
• [or 1/3tsp no-sodium salt + 2/3tsp sea salt]
• 2tbsp lemon juice
• 2tbsp distilled/white vinegar
• Optional:
• 200ug lithium orotate
• 1 drop Lugol's solution, 3-7% (1.5-3.5mg iodine)

Rational:

• Start with very pure or distilled water to minimise toxins/contaminants.
• Silica, used to remove excess aluminium, set at similar levels to Fuji water which is shown in studies to be effective.
• Magnesium, needed for over 300 enzymes, most people are very deficient in this mineral due to soil depletion, diluting it in water is a great way to increase intake.
• Salts (sea and low-sodium), these provide the electrolytes sodium and potassium, the sea salt provides trace minerals including a bit of magnesium.
• Lemon juice and vinegar, these improve the taste and absorption of water, blunt glycaemic responds (stops high blood sugar peaks), and also remove excess iron.
• Lithium, for mood support. Populations with water low in lithium are more prone to violent crimes and suicides.
• Iodine, needed for thyroid health and prevention of certain cancers, set a base therapeutic level; if you eat seaweed then this isn't needed though.

If anyone has anything else they think should be in the mineral water, then feel free to comment below or send me an email :)




Update (20/12/13) - Version 2:

Mineral water #0: Water Base

• 2,000ml distilled or very pure water
• 2tbsp vinegar, white/distilled
• 2tbsp lemon juice
• 1-2tsp Himalayan pink salt or similar
• 200mg silica / silicic acid
• 200ug lithium oratate (optional)
• 1.5-3.5mg iodine (1 drop 3-7% Lugol's solution)

Mineral Water #1: Magnesium

• 315mg magnesium citrate (1/2tsp powder)
• 250-500ml mineral water #0

Mineral Water #2: Vitamin C

• 2.5g vitamin C / ascorbic acid
• 250-500ml mineral water #0
• Update (21/12/13) - version 2.1: Due to acidity issues with my teeth last night, always add some bicarbonate of soda (bicarb) in equal amounts to the ascorbic acid.

All can be sweetened/flavoured if desired. Drinking one of #1/2 plus two plain #0s, results in exactly my original recipe, minus the low/no-sodium salt which I am removing because I feel the potassium isn't that critical really.

Why the split? For better timing of nutrients, for example drink #1 before bed. #2 is optional, drink #0 through the day.

What to do if you can't filter crappy water (thanks for the reminder Raphi!):

• Chlorine: boil water and allow to cool to room temperature, the chlorine will off-gas, so best to place outside or by open window to cool.
• Chloroamines: add 1/4tsp vitamin C / ascorbic acid to the water base to neutralise chloroamines.
• Fluorine: Use 4-8 drops 3% or 2-4 drops 7% Lugol's solution depending on level of fluoridation, this won't remove it from the water but combat the effects of the fluorine in your body.

Boosting Glutathione

We've talked previously about how important good glutathione levels are, so here we'll talk about how to boost them naturally and also with supplements. First a quick review of how glutathione is made:

1. First methionine is converted to homocysteine, via methyl acceptors (opposite of donors).
2. Next homocysteine is converted to cysteine via vitamin B6 with the addition of serine.
3. Cysteine combines with glycine and glutamate, using selenium to make glutathione.
   

So the nutrients needed to make glutathione are:

• Methionine + vitamin B6 (to make cysteine)
• Then, cysteine + glycine + glutamate + selenium
  

The best foods source of each 'ingredient' is:

• Methionine: eggs.
• Vitamin B6: red meat.
• Cysteine: red meat, eggs.
• Glycine: gelatin (heads, hooves/feet, tails, ears, skin, cartilage, powder/sheets, etc)
• Serine (inter-converts with glycine): any protein source.
• Glutamate: any protein source.
• Glutamine (inter-converts with glutamate): any protein source.
• Selenium: kidneys, brazil nuts.
  

Notice red meat and eggs come up multiple times, this means they're very good foods to include in your diet if you want to boost glutathione production. But the other components are equally important, so brink your gelatin-rich broth and eat your kidneys/brazil nuts.

Ok, now you're eating everything you need to make glutathione, lets make sure you make as much as possible. Methods for doing this include:

• N-acetyl-cysteine: this is a special 'locked up' form of cysteine that really helps boost glutathione production. Never supplement normal cysteine as bacteria tend to get to it first and use it for their own reproduction. Suggested dose: ~600mg.
• Milk thistle/Silymarin: this is a herb (and its active ingredient) that helps the liver to work properly, boosting its functions, including... you guessed it, making glutathione. Suggested dose: 100-200mg silymarin. This supplement is boosted when taken at the same time as choline, so eat some egg yolks with it for maximum effect.
• Turmeric/curcumin: this spice boosts glutathione S-transferase which is hormone that regulates glutathione production. Suggested dose: 1tsp turmeric.
• Whey protein: this boosts glutathione, due to its natural cysteine and other nutrients.
  

Ultimate glutathione production method:

• Diet based on red meat (for cysteine, B6, zinc), with additional egg yolks (choline), poultry liver (folate), kidneys/brazil nuts (selenium), and gelatin-rich bone broth (glycine).
• Supplements: 600mg N-acetyl-cysteine, 200mg silymarin as milk thistle, 1tsp turmeric, 1 scoop whey protein powder.
  

Glutathione nutrients for the carnivore RDA example diet (link):

• Methionine: 2,180mg.
• Cysteine: 1,130mg.
• Vitamin B6: 1.66mg.
• Glycine+serine: 13,700mg.
• Glutamate+glutamine: 13,510mg.
• Selenium: 194ug.
  

2000 calories of rib-eye (877g raw) would have:

• Methionine: 4,600mg.
• Cysteine: 1,700mg.
• Vitamin B6: 3.6mg.
• Glycine+serine: 15,300mg.
• Glutamate+glutamine: 27,600mg.
• Selenium: 212ug.
  

As we can see, both diets are strong glutathione producers. But I don't recommend a diet of JUST red meat steaks for many other reasons already stated in this blog, but glutathione production is not one of my concerns with such a diet. Bare in mind the rib-eye diet has a lot more protein overall too (~170g versus ~100g), so has more of the critical amino acids just from bulk.

Recommended intake:

• Methionine: 2,000mg.
• Cysteine: 1,500mg. ???
• Vitamin B6: >0.016mg/g protein.
• Glycine+serine: 13,500mg.
• Glutamate+glutamine: 20,000mg. ???
• Selenium: 200ug.

Inner Wolf Unchained

I'm currently writing a book on nutrition, with my good friend Danny Albers of Primal North assisting. It's called 'Inner Wolf Unchained', with a subtitle of 'Eat and Train like a Wolf to Get Healthy and Conquer Survival of the Fittest'.

It will cover our evolution in Africa, and how it essentially makes us fur-less wolves; it examines from the base up what we need and don't need in our diet; it looks at the latest science to understand what amounts/ratios of macronutrients and micronutrients we need; it draws this all together into a simple and easy to follow diet framework; it looks at the science of exercise and what forms are best for us; it looks at what supplements one should take based on what they don't eat to ensure complete nutrition for optimal health. The book will include plenty of meal plans and recipes too.

Here's an extract:
"There are certain nutrients we must get from our diet, such as essential amino acids, essential fatty acids, fat- and water-soluble vitamins, macro, trace, and ultra-trace minerals, and energy itself.

There are many nutrients the body requires but can make for itself, but only partially so, such as glucose (with heavy exercise), fat, choline, co-enzyme Q10, semi-essential amino acids, and many others.

Then there are substances in our food that negatively affect our health, either by blocking nutrients or doing direct damage, including fructose, gluten, excessive blood glucose, linoleic acid, anti-nutrients such as phytic acid, tannins, and many other phytochemicals.

We must balance these three aspects together in order to achieve maximum health and wellness."

Carnivore RDA Chart, The End of A Long Road

Amino Acids:

Nutrient	Unit	USDA RDA	cRDA	NPCD*	Recommended Foods
Total Protein	g/kg	0.8 (54.5g/150lbs)	1.2/lean (82g/150lbs@20%bf)	97g (1.78g/kg lean)
Serine+Glycine	mg/kg	N/A	200 (13,620mg/150lbs)	13,700mg	Glycine: gelatin Serine: muscle meat
Methionine	mg/kg	10.4 (708mg/150lbs)	30 (2,088mg/150lbs)	2,180mg	Egg yolks

Vitamins:

Nutrient	Unit	USDA RDA	cRDA	NPCD*	Recommended Foods
Vit A	IU	3,000	10,000	10,927	Liver, egg yolks, dairy fats, cod liver oil
Vit B1	mg	1.2	0.5	0.52	Pork meat, pork heart, lamb kidneys
Vit B2	mg	1.3	N/A	3.10	Liver, kidneys, heart, egg yolks, meat
Vit B3	mg	16	N/A	25	Liver, fish, kidneys, heart, tongue, meat, egg yolks
Vit B5	mg	5	N/A	7.47	Liver, kidneys, egg yolks, heart
Vit B6	mg	1.3	0.016mg/g protein (1.6mg/100g protein)	1.66 (0.0171mg/g protein)	Liver, kidneys, tongue, heart, meat
Folate	ug	400	~200	191	Liver especially poultry, egg yolks
Vit B12	ug	2.4	12+	27	Liver, kidneys, meat, egg yolks
Biotin	ug	30	30+	50 (estimate)	Egg yolks, liver
Choline	mg	550	~550	534	Egg yolks, liver, meat
Vit C	mg	90	0	17 (when raw)	Raw organs, but none strictly needed
Vit D	IU	200	Use blood levels	469	Oily fish, pastured lard; sunlight. Vit D should always be eaten/ supplemented based on blood levels
Vit E	mg	15	0.65mg/g PUFA	5.60 (0.67mg/g PUFA)	Grass-fed fats/yolks/dairy has more, though plenty in grain-fed
Vit K1	ug	120	0	53	None needed with sufficient K2
Vit K2	ug	N/A	80?	70.3-86.6+ (estimate)	Grass-fed fats/yolks/dairy has more, though plenty in grain-fed; supplement 1mg every 2 weeks if paranoid

Minerals:

Nutrient	Unit	USDA RDA	cRDA	NPCD*	Recommended Foods
Calcium	mg	1,000 (WAPF: 680)	544 min: 200-300	558	Bone broth, egg shells, fish with bones
Phosphorus	mg	900 (WAPF: 1,300)	878	1,149	Protein-rich foods, bones
Magnesium	mg	420	420 ideally, ~170 minimally	418	Supplement 300mg citrate
Potassium	mg	4,700	2-3,000	2,567	Losalt, meat (juices from cooked meat very rich)
Sodium	mg	1,500	3-5,000	3,946	Salt, meat (juices from cooked meat very rich)
Copper	ug	900	1-2.4	1.28	Liver, kidneys, heart
Zinc	mg	11	12-29	15.40	Muscle meat
Selenium	ug	55	~200	194	Pork, kidneys (pork best)
Manganese	mg	2.3	1	1.24	Spices, tea
Iron	mg	18	18	20	Liver, heart, muscle meat
Iodine	ug	150	1,000-3,000	Without seaweed: ~600 With seaweed: ~3,115 (estimates)	Shellfish, fish, sea weed
Molybdenum	ug	45	60?+	70.5+ (estimate)	Liver
Chromium	ug	25-35	50-200	260+ (estimate)	Liver

* Nutritionally Perfect cRDA Carnivore Diet:
10oz 30% fat beef/lamb (~284g)
80g beef/lamb tallow
2oz mackerel (~57g) [or 75g salmon or 40g sardines or 5g/week DHA fish oil]
1 2/3oz pork liver (~47g)
1 1/4oz pork kidney (~43g)
2 large eggs

3tbsp gelatin powder (or equiv from feet/hooves, skin, heads, tails, ears, cartilage), and
~1 cup bone broth (alt: egg shells)

2g potassium salt
9.5g sodium salt (unrefined sea salt recommended for ultra-trace minerals)

Technically plant foods:
1/2tsp tea or other manganese-rich spices (or alternatively shellfish such as mussels)
1g  kelp/kombu flakes, for iodine (or shellfish)

Supplements:
300mg magnesium citrate

Nutrition:
~2100 calories, 97g protein (20% of calories), 2.3g carbohydrates (<1%), 184g fat (80%).

Ratios, etc.:
Calcium:Phosphorus = 0.49 (WAPF ideal 0.52)
Zinc:Copper = 12.0 (ideal ~12)
Potassium:Sodium = 0.65 (ideal ~0.6-0.66)
Omega-6:omega-3 = 2.6 (ideal <2, good <4)
Saturated:Mono-unsaturated = 1 (ideal ~1)
Poly-unsaturated = 3.6% of calories (ideal ≤4%)

- - - - - - - - - -
Tweaks:

Less salts:
Using no potassium salt and only 3.5g salt maintains the potassium:sodium ratio at a lower total level of these minerals. This should be fine for those who've been on a ketogenic diet for a while rather than those just starting.

Cod liver oil:
Substitute 4.5ml cod liver oil for the pork liver and use 3g beef liver or 4g lamb liver for the copper.

Trace Minerals

Selenium:

The USDA RDA for selenium is 55ug, but studies show that 200ug daily is the best for a healthy immune system (link and link), and preventing heart disease (link) due to it's co-factor role in glutathione peroxidase (do we really need reminding how important glutathione is?). This is easy to achieve 200ug if kidneys are included in a carnivore diet, the best plant source is brazil nuts (1-2 a day only, too much can cause toxicity).


Iodine:

Iodine is important for a healthy metabolism, as it's needed to make the thyroid hormones (and selenium is needed to turn inactive T4 into the active T3, another reason to get plenty of selenium). The USDA is 150ug, but this is the bare minimum determined needed to stop goitre (enlargening of the thyroid gland), the Japanese get 1-3mg a day (666-2,000% USDA RDA) (link) mostly from seaweed and so this amount seems perfectly safe. Also iodine deficiency seems to play a big role in breast cancer (link and link), the Japanese have very low breast cancer rates possibly due to their high iodine intakes. For these reasons I shall be recommending more iodine than the USDA, mostly from kelp/kombu flakes (these are the most iodine rich seaweeds: "Most Kelp or Kombu has about 2500 mcg/gm" (source)), shellfish are also another good source but just don't provide anywhere near as much iodine as kelp/kombu do. These will also provide many other trace minerals they we may not even realise are needed for health yet, so are a great addition to anyone's diet.

Cattle fed plenty of seaweed or in iodine rich soil (coastal) will have much more iodine in their flesh and organs, same for eggs of chickens fed seaweeds, but still no where near eating the seaweed itself.


Sulphur:

There are two main sources of sulphur from foods: thiols in plants, and the sulphur containing amino acids (cysteine and methionine) in animal foods. Thiols are good for their antioxidant properties but aren't good sources of usable sulphur for bodily structures, for that we need cysteine and methionine. Cysteine and methionine (via cysteine) are the best for boosting glutathione levels. I'm happy that a diet rich in eggs and meat will have plenty of sulphur.


Chromium:

The USDA was 50-200ug and has been lowered to 35ug for men and 25ug for women. Liver is a very rich source, and beef, eggs, chicken, oysters are also good sources. Chromium deficiency is rare and the only ones needing supplemental chromium are diabetics still eating lots of refined grains. I'm happy that a diet based on meat, eggs, with some liver will have more than enough chromium especially considering that less will be needed on a diet lacking dietary carbohydrates.


Biotin:

This vitamin is needed for gluconeogenesis so is important for a carnivorous diet, the best sources are egg yolks and liver, cheese also has some; raw egg whites without yolks can cause deficiency though. First signs of deficiency are hair loss and skin problems, though deficiency is rare unless consuming lots of raw egg whites or your food intake is just shakes or an IV without biotin.

From wiki: "Pregnant women tend to have a high risk of biotin deficiency. Nearly half of pregnant women have abnormal increases of 3-hydroxyisovaleric acid, which reflects reduced status of biotin.[25] Several studies have reported this possible biotin deficiency during the pregnancy may cause infants' congenital malformations, such as cleft palate." (link)

For this reason egg yolks and liver are even more vital for pregnant women. In China eggs are considered a fertility food and pregnant women will eat up to two dozen a day to ensure an intelligent child.

The RDA for adults is 30ug, and 35ug for pregnant women; though this amount for pregnant women is likely too little. 30ug can be found in 4oz/114g liver or ~1.5 eggs (source). For this reason I recommend plenty of eggs and liver in a carnivore diet, and lots during pregnancy/lactation.


Molybdenum:

This mineral is needed for xanthine oxidase to work, which if you've read my previous posts you'll recognise as that all important enzyme that makes uric acid to help us ward off scurvy on an ascorbic acid-free diet. It's also used for metabolising the sulphur-containing amino acids, cysteine and methionine, so is important in glutathione production.

Livers contain about 150ug per 100g, and very small amounts in eggs. The RDA is 45ug for adult, so a diet containing plenty of liver will have no issues. My new perfect carnivore diet contains ~70ug molybdenum.


Other Trace Minerals:

These include boron, nickel, strontium, vanadium, lithium, and silica. Because I can't find much data on food sources (the latter two should come from our water though) and nutrient interacts, I won't be including them in the cRDA project. Once more is known about these minerals and their need though I will expand the cRDA to include them.

Lithium and Silica:

These mineral should come from our water rather than food, but most water has them removed. When buying bottled water look for one listing silica on the label, most water has 5-25mg/L (source), Fiji brand is best for silica (920mg/L) though expensive, any that lists it on the label is likely a good source and also check with your water provider to the content in your tap water; other good sources of silica are edible clays. Low lithium in water levels is linked to suicides (source), very high levels are used to treat bipolar and schizophrenia, but tiny amounts prevent mental disorders such as criminal behaviours (source) in the general population, so much so that some scientists are calling for adding lithium to the water in areas where the content is low! Again ask your water provider, most bottle water is unlikely to list lithium.

A link on silicon.

What can we learn for breast milk? Part 2: Micronutrients

All these calculations use 84 grams of protein worth of breast milk, to normalise it to the minimum needed for an adult (see part 1).

I'm also aware that the nutritional content of breast milk varies depending on the mother's diet but using the USDA data for it means we get a nice average of an American (which I'm aware may not be the best nutritionally).


Here's my CRONometer print out for the breast milk at 84g of protein (ignore chromium, there's just no data for it):

Vitamins

Let's start with vitamin A, this amount of breast milk provides ~16.5kIU vitamin A which is quite a bit and more than what I or the WAPF recommend (10kIU). Infants are growing rapidly and so need more vitamin A though, so this is fine.

With the B vitamins everything is in normal meaty amounts, except the B2 is slightly higher and B5 is a lot higher. B5 is needed for forming acteyl-coA so may be high due to the infant's high energy requirement, it's also used in the synthesis of fatty acids and cholesterol so again good reasons for it to be high. B6 is also fairly low, but the milk provides huge amounts of folate and choline instead so homocysteine levels will be fine. The WAPF comments that most mothers are also deficiency in B6 due to low meat consumption  The amount of choline is so incredibly high due (9 large eggs worth) to its other use for helping the developing brain. As previously discussed the amount of choline/folate/B6 needed are all interrelated.

Vitamin C is higher than would be gotten eating a carnivorous diet, but the protein needs for infants is very high and so little is left over to make uric acid, so breast milk supplies ascorbic acid instead.

Vitamin D is fairly low but almost all mothers are deficient in this vitamin. It's one of two supplements I recommend to everyone (the other being magnesium as soils are depleted), and should be supplemented based on your blood levels rather than a set IU amount.

The vitamin K is K1, as the USDA doesn't measure K2. It's quite low compared to the RDA and about twice the amount in 2000 calories worth of grain-fed rib-eye (grass-fed meat would have more K1 though), but as previously discussed K2 can do clotting like K1 so this is no problem.

Minerals

As previously discussed in my post about calcium, breast milk in the amount an infant drinks (rather than 84g of protein worth) only provides ~320mg calcium a day and this should be fine for an adult too.

Magnesium is lower than the RDA but still about double provided by just meat. Again I'll note that most mothers are deficient in magnesium due to the soil being depleted and that's why I recommend supplementing it.

Phosphorus is at about half the level of calcium which is why I originally recommended a 2:1 calcium:phosphorus ratio but further research shows our calcium needs are lower. The total amount is similar to that found in 2000 calories of rib-eye so I'm happy that this amount is ideal for an adult.

The level of potassium is almost at the USDA RDA which is interesting and may warrant the use of more potassium in a carnivore diet. But the ideal potassium:sodium depends on whether you're in ketosis or not, with ketosis meaning more sodium is needed per potassium. Infants, as far as I'm aware are not in ketosis due to the lactose in breast milk and so have more potassium and less sodium (or at least only mild ketosis). Additionally the level of sodium in breast milk is quite low as infant's kidneys struggle somewhat with sodium initially and slowly improve as the infant grows. This means that an adult in ketosis needs much more sodium and less potassium.

With selenium, the level is almost three times the RDA, but similar to the amount recommended by most for proper thyroid health (200ug), again American mothers are likely to be slightly deficient in this so 150-200ug is properly the best amount.

The manganese is quite high in breast milk, and is needed for mitochondrial functioning so may be high due to an infant's high energy requirements.

The iron in breast milk is very low, as it is in all mammal milks, as iron interes with zinc absorption and zinc is needed for the developing brain. Infants have large iron stores when born (or at least they should do if the placenta is allowed to return the infant's blood back to its body after birth and not clamped early like is usually done in the developed world; as much as half an infant's total blood can be lost to the placenta with early cord clamping, which is a huge amount!) so little is needed in the diet until at least 6 months old (older if delayed clamping) and the first weaning foods should be high in iron such as meat or liver.

The copper in breast milk is actually pretty low, only ~0.6mg total a day (rather than per 84g protein) and an infant will slowly run down the coper stored developed before birth similar to what it does for iron, again meaning the best weaning food would be liver (from beef or lamb, not pork) as it's rich in copper too. This means that our copper requirement is more than ~0.6mg per day, and as discussed in the phytic acid nutrients post I recommend 1-2.4mg of copper a day.

Conclusion

We can see that looking at the vitamins and minerals of breast milk, again in the context of the body it's designed to nourish, gives is good insight into the nutrition of an adult. I points to us needing more retinol, calcium, magnesium, potassium, sodium, selenium, and copper than is normally achieved just eating fatty meat. This points to the need include a few other choice animal foods in our diets for optimal health.

What can we learn from breast milk? Part 1: Macronutrients

Warning: post contains maths!

Breast milk is 1% protein, 6.9% carbohydrate and 4.4% fat by weight, or 5.6% protein, 38.8% carbohydrate and 55.6% fat by calories. It is low in protein and high in both fat and carbohydrates... Or is it?

Protein

Due to babies huge energy requirements*, they actually get ~0.89 grams of protein per pound body weight**, but this is more than an adult needs as the infant is growing rapidly so this amount can be seen as the maximum we would need (especially considering formulas made with higher protein levels are toxic to infants). This translates as 150lb adult needing a maximum of ~134 grams of protein a day, and at 2000 calories a day, this is 27% of calories.

* An infant weighing 5kg/11lbs needs 700 calories; this is ~64 calories per pound. A 150lb adult may need 2000 calories, or ~13 calories per pound. The infant’s energy requirements are almost five times that of an adult’s on a per weight basis.

**700 calories @ 5.6% protein = 39.2 calories from protein = 9.8g protein / 11lbs = 0.89 protein/lbs.

How little protein do we need though if that's the maximum? Well many keto dieters eat as little as 60g of protein a day fine (~12% @ 2000 calories), but this is usually done in fear of slightly higher fasting blood glucose levels on a ketogenic/low-carb diet even though such a thing is perfectly natural and safe. They're eating the absolute minimum they can get away with, which I think is a poor strategy. The body has an efficient system for getting rid of excess protein, via urea and uric acid. As previously discussed uric acid is a potent antioxidant and why I think we don't get scurvy on all meat diets, so protein in excess of our pure tissue requirement can be seen as a good thing!

Phinney/Volek in The Art And Science of Low Carb Living/Performance generally recommend 1.5g/kg protein (~0.68g/lb), this is ~102g at150lbs (~20% @ 2000 calories). Other recommendations include 0.7+g/lb of lean mass (84g/150lbs@20%bf, 17% @ 2000 calories), this seems much more reasonable minimum. Basing your protein needs off lean mass rather than whole mass is much smarter, as fat tissue doesn't increase protein requirements but muscle mass does. 102g of protein is almost exactly half way between 84g and 134g, so is a good middle ground target of protein intake.

Carbohydrates

The brain is the biggest user of carbohydrates in the body; in infants, it uses 50% of the body’s total energy requirements, but by adulthood only uses up 20%. This means the adult brain uses 40% of the energy required by an infant brain: this works out to ~15% of calories from carbohydrates (38.8% x 40% = 15.5%).

BUT... the carbohydrate source is lactose, made of glucose and galactose. Now galactose is very special, it's not used as an energy fuel like glucose, it's used for myelin synthesis (that is making nerve insulation), this is why human breast milk is so high in lactose, for the galactose! So that ~15% becomes ~7% of calories coming from carbs for an adult (~38g @ 2000 calories).

BUT... we can make glucose from protein (via gluconeogenesis) and glycerol from fats. Gluconeogenesis is constant regardless of diet, as we've discussed before, but as far as I'm aware there is no cap on glycerol->glucose synthesis. Estimates are at about 10% of whole fat can be converted to glucose from the glycerol.

The actual dietary requirement for carbohydrates is zero, and even infants do very well on ketogenic diets; we can synthesis all the glucose we need (which is less while in ketosis) from GNG and glycerol. The main reason for muscle wastage in starvation is it's being used for GNG (which is constant even in starvation), this supplies the glucose requirement easily and blood glucose levels remain steady right up until you die.

Fat

The rest of the body’s calories come from fat, which in an adult eating ~27% protein and ~7% carbohydrates is ~66%, or ~147 grams of fat on a 2000-calorie diet. This would be the minimum fat, as this is the maximum protein and carbohydrates we need. Taking in our minimum 84g protein and no carbs would mean we need to eat 83% of our calories as fat or ~184 grams of fat on a 2000-calorie diet.

Summary

So understanding the macronutrient ratios of breast milk in context of the body it is designed for gives up a good idea of what ratios are healthy for an adult human. This works out to ~17-27% protein, ~0-7% carbohydrates, ~66-83% fat, or 84-137g protein, 0-38g carbs, and 147-184g fat on a 2000-calorie diet. Such a diet would almost always be ketogenic (very metabolically damaged people may not handle even 38g carbs).

As calorie expenditure increases, say due to increased exercise, the extra calorie should come from fat, little extra protein or carbs are needed. During very heavy exercise some non-insulin-stimulating carb source may be used to aid recovery such as super starch, palatinose, or possibly pure fructose in order to refill glycogen stores (as discussed previously our ability to refill glycogen is limited by GNG and is less than that of other carnivores).