In this article:
"Sodium and potassium The second factor differentiating the author's studies from many others is optimized mineral nutriture, which has benefits for both cardiovascular reserve in the short term and preservation of lean body mass and function over longer time periods. The Inuit people lived much of the year on coastal ice (which is partially desalinated sea water), and much of their food consisted of soup made with meat in a broth from this brackish source of water. When they went inland to hunt, they traditionally added caribou blood (also a rich source of sodium) to their soup. With these empirically derived techniques, the Inuit culture had adapted the available resources to optimize their intakes of both sodium and potassium.
When meat is baked, roasted, or broiled; or when it is boiled but the broth discarded, potassium initially present in the meat is lost, making it more difficult to maintain potassium balance in the absence of fruits and vegetables. Because our research subjects were accustomed to eating meat, fish, and poultry prepared as something other than soup, we chose to give them most of their sodium separately as bouillon and a modest additional supplement of potassium as potassium bicarbonate. With these supplements maintaining daily intakes for sodium at 3–5 g/d and total potassium at 2–3 g/d, our adult subjects were able to effectively maintain their circulatory reserve (ie, allowing vasodilatation during submaximal exercise) and effective nitrogen balance with functional tissue preservation."
I thought ancient man had a sodium to potassium ratio of more like 1:10-16, favoring potassium.
This only applies to ketogenic or VLC diets really. When insulin falls low enough sodium is not retained at the normal rate. Either intake has to increase or the hormone aldosterone steps in to preserve sodium and hence circulating volume. The cost of that is high aldosterone causes low potassium (sodium is reabsorbed from the kidney's filtering system at the expense of potassium), so eating more salt to bypass that mechanism is wiser and will spare potassium too. Relying on aldosterone rather than higher salt intake is the reason for many low carb initiation symptoms.
That does seem to be a bit at odds with other information i have seen
This report; Paleolithic vs. modern diets - selected pathophysiological implications
estimates a potassium intake of 10,500mg/d & sodium as 768mg/d for a Paleolithic human based on 3000 kcal/d, 35 % animal: 65 % plant subsistence. That's a potassium:sodium ratio of nearly 14:1
Even the US DRI's have a ratio in favour of potassium; link to pdf
Last i checked the inuit are only a thousand years old, hardly 'paleo' and last i checked had problems with severe atherosclerosis and osteoporosis with a life expectancy of under 40 years of age.
until the end of the paleolithic humanity was stuck on africa, a VERY sodium poor and potassium rich continent, why then would we evolve to have a reliance on a very scarce mineral and need it in greater amounts ratio-wise to something found practically everywhere?