Thus it seems unlikely to me that isolated coastal Eskimos who ate kelp suffered from any activity or mineral deficiency that could account for their unusual bone metabolism and mineral loss with age. Inland Eskimos who ate less fish and kelp may have had a more difficult time getting adequate calcium and magnesium, since without the kelp this diet would have only 42% of the recommended level of magnesium and about 400 mg less calcium, and without the sardines the calcium intake would fall very low.
It does seem possible that excessive vitamin A could have played a role, at least in some cases where people consumed liver from certain species. Subacute deficiency of vitamin C may also have played a role. On page 72 of NPD, Dr. Price summarized the omnivorous Eskimo diet: "Eskimos were able to provide their bodies with all the mineral and vitamin requirements from sea foods, stored greens and berries and plants from the sea." I don't know what other greens or berries the Eskimos ate, but they would have increased the vitamin C content as well. Thus, I do not feel certain that either of these can completely account for the degree of bone mineral loss observed in Eskimos.
I do want to emphasize the importance of kelp in this menu. If you take it out of the outlined diet, this makes the diet deficient in vitamin E, magnesium, manganese, potassium, and thiamin. It appears that by Weston Price's report, high nutrient density plant foods (seaweeds, greens, and berries) played an important nutritive role in the Eskimo diet.
Shortly after I posted this I noticed that I did not feel confident in my supposition that Eskimos ate the amount of kelp I proposed in my analogue diet, but I did not have time to edit it. This reminded me that when I posted on the Masai Use of Herbs, in response to a comment I stated that I would post on plant foods used by Eskimos. Then I received comments from Stephan and Tom (below) that expressed the same doubt. I got ahold of two old reports on plants used as food by Eskimos, and from these two papers it appears that coastal Eskimos did not use kelp in anywhere near the quantity I thought possible. It appears that they actually used more of land plants than seaweeds.
So in my next post on this subject I will present a revised Eskimo analogue diet. Suffice it to say the without kelp, the Eskimo diet has multiple mineral deficiencies that could promote osteoporosis.