As we have discussed possible Inuit diet profiles for their nutrient contents relevant to bone health in the series pertaining to Eskimo Diet and Health, I have come to realize that the idea that you can replicate Inuit diet and health by eating a diet composed of any selection of modern meat and fat does not hold water. For example, thanks to help from Greg, we found that to ensure adequate intake of manganese, Inuit had to eat shellfish; that a diet of meat and finfish alone fell short.
This fact came very clear to me when I read through the paper on vitamin C in the Inuit diet discovered by my able commenter Greg (Thanks Greg!): "Vitamin C in the Inuit diet: past and present," a master's thesis written by Karen Fediuk of the School of Dietetics and Human Nutrition at McGill University, Montreal, Canada, July 2000.
This paper demonstrates that the Inuit ate a variety of wild plant and animal tissues that supplied vitamin C. Further, even if you assume that Inuit only ate animal products most of the time, many of the marine animal tissues they consumed had very significant contents of vitamin C not found in modern livestock products, even from grass-fed animals.
For example, among common traditional Inuit foods, cisco eggs contain ascorbic acid at levels of 49mg/100g, whale skin 36mg/100g, and ringed seal brain up to 28mg/100g. Compare these to spinach supplying ascorbic acid at 51mg/100g, oranges at 50mg/100g, cabbage at 47mg/100g, and tangerines at 31mg/100g.
Frozen and raw muscle meats consumed by Inuit contain ascorbic acid at 1mg/100g on average. In contrast, modern muscle meats generally supply no vitamin C at all in a 100g portion, and liver only about 20-30mg/100g.
Fediuk found that in a traditional Inuit diet, absent modern foods, vitamin C intake would range from 90mg/d up to 262mg/d, depending on season (table 13.5 from her thesis below):
In winter, kelp, boiled ringed seal meat, raw whale skin, and raw ringed seal meat provided 92% of Inuit winter intake of vitamin C, which according to the table above amounted to 90mg/d. So these 4 items provided them with >80mg of vitamin C. In late spring, raw whale skin provided 71% of their vitamin C intake, with mussels providing the next largest share at only 10% of the total 185mg/d intake (from table above). That means the whale skin alone provided 131mg of vitamin C per day. I know of no product of modern, even grass-fed, livestock that will come anywhere close to this (if anyone else does, please let me know).
In contrast, someone eating a strictly carnivorous meat-and-fat diet composed of modern livestock meats, even if strictly grass-fed, would not consume anywhere near this amount of vitamin C on a daily basis. Therefore, a modern "zero carb" diet composed of terrestrial livestock is not a replica of an Inuit diet, and we can't expect it to produce the same health outcomes of a traditional Eskimo diet.
As I noted in Masai Use of Herbs, to replicate the diet and health of the Masai you have to eat the same quality of food (grass-fed cattle products) and use the herbs they use. Similarly, to replicate the diet and health of the precontact Inuit (if that was desirable) would require eating exactly the same variety and types of foods as the Inuit ate–shellfish, fish with bones, seal eyeballs, walrus liver, seal brains, whale skin, kelp, berries, partially digested contents of caribou stomachs, and so on–in proportions similar to what Inuit ate.
If you do something different from the Eskimo diet, you can't rationally expect that you will have the same results. Eskimos' experience certainly did not prove that a diet of modern meat and fat will keep you healthy without plant food intake.
One last interesting aspect of this paper. According to Stefansson, Eskimos ate a diet providing 70-80% of energy as fat and only 20% as protein, claimed to be required to prevent protein poisoning. Others have claimed that humans can tolerate no more than 35% of calories as protein for extended periods of time due to limits on the liver's ability to synthesize urea from waste nitrogen, and I have taken this as a demonstrated fact.
Therefore, I was surprised to find the following table in Fediuk's thesis:
The sources she cites estimated the coastal Inuit diet providing a minimum of 43% of calories and a maximum of 56% as protein, and fat ranged from only 43% to 53%. These figures all have carbohydrate intake of less than 7%, so I don't think we can dismiss them as results of incorporation of modern carbohydrates (i.e. post-contact diets). They describe the Inuit diet as having roughly equal caloric portions of protein and fat, not the modern high-fat low-carb diet.
A 3000 kcalorie diet (necessary for a young active hunter) providing 43% of calories as protein contains 322g of protein; with 56% protein it would provide 420g of protein. This exceeds levels Stefansson claimed and apparently demonstrated (in Effects on humans of 12 months exclusive meat diet) to be acutely toxic, at least in his own case.
I will have to do some more research to determine whether protein intakes of this level (twice what I proposed in my models of Inuit diet), from meat (not purified proteins) could have any influence on bone mass. It has been my impression so far that studies supposedly proving that dietary meat protein has no detrimental effect on bone health have utilized much lower protein intakes in the range of 2-3 times the RDA, whereas if this data is correct, the Eskimos were consuming 6-10 times the RDA.