Originally Posted by nelie
How do they not get scurvy and other nutrient deficiencies from nutrients found only in plants?
Some of the nutrients we think of as "found only in plants" really aren't. Sea mammal blubber (fat from whale and seals), is reported to be exceptionally high in Vitamin C (with more vitamin C per kilo than oranges).
In the modern SAD (standard american diet) many of the nutrients we can get "only from plants" can come from other sources, but they're sources we're not normally willing to eat (insects, organ meats, blood, skin, bones...).
The meat-eating people referred to in the reference study were Inuit people (Eskimos) of Greenland, Canada, and Alaska and while their traditional diet is "almost exclusively animal protein," that almost is very important, because they do eat some plant foods, just not many and not all year round. Blueberries and related berries for example are very high in Vitamin C (which is the nutrient that prevents scurvy), and the Inuit do eat berries when they're available (often mixed with seal blubber (also high in vitamin C) to create a traditional treat akutaq, called Eskimo ice cream).
The Inuit also used plants medicinally, for example brewing a tea or tonic from stinkweed.
Neanderthin and other ancestor and "primal" diets often quote the research of these people as well as other aboriginal hunter/gathering people who eat very little plant food (or at least receive very few calories from plant foods, but use plants as seasonings and medications)
Exercise is also a variable too often left out of the equation. Hunting and hunting/gethering cultures generally require quite a lot of movement (and physical games are very popular in traditional Inuit culture).