I started a carnivore diet a couple years back, and it's worked out very well for me - far better health, better mood, etc.
One of the things that almost all carnivores believe in is plenty of salt. The most strict carnivore diet is called the Lion diet, and is supposed to be extremely helpful especially for people suffering from autoimmune disorders. On the Lion diet, you eat only fatty ruminant meat (mostly beef), water, and...salt. So, the implication is that salt is critical.
Mainstream nutritional science also says that salt is necessary, but should be limited ("Sodium
Sodium is an essential nutrient", https://www.dietaryguidelines.gov/sites/default/files/2021-03/Dietary_Guidelines_for_Americans-2020-2025.pdf).
But here's the no-salt point of view. I've had the pleasure of reading some of Vilhjalmur Stefansson works. Vilhjalmur Stefansson was an explorer and anthropologist in the Arctic before World War I, and spent many years living with the Eskimo, hunting, fishing, eating, and living very similarly to them.
The main reason I learned about Stefansson is that he wrote and talked extensively about the carnivore diet, almost 100 years ago. He believed that the Eskimos, when they were still about 97% carnivore (before they adopted the western diet), were far healthier than Westerners, and had almost none of the "diseases of civilization.
Some of his more famous books are The Friendly Arctic, and My Life With The Eskimo. You can get all of them for free on annas-archive.org (https://annas-archive.org/search?q=Vilhjalmur+Stefansson). I highly recommend them.
Anyway, in the book My Life With The Eskimo, there was some information about the Eskimo's salt consumption that surprised me. Basically, they reject salt completely (until they became accustomed to it, and at that point they are similar to non-Eskimos in their desire for salt).
Most people are in the habit of looking upon the articles of our accustomed diet, and especially upon salt, as necessities. We have not found them so. The longer you go without grain foods and vegetables the less you long for them. Salt I have found to behave like a narcotic poison — in other words, it is hard to break off its use, as it is hard to stop the use of tobacco; but after you have been a month or so without salt you cease to long for it, and after six months I have found the taste of meat boiled in salt water distinctly disagreeable.
In the case of such a necessary element of food as fat, on the other hand, I have found that the longer you are without it the more you long for it, until the craving becomes much more intense than is the hunger of a man who fasts. (The symptoms of starvation are those of a disease rather than of being hungry.) Among the uncivilized Eskimo the dislike of salt is so strong that a saltiness imperceptible to me would prevent them from eating at all.
This circumstance was often useful to me later in our travels about Coronation Gulf, for whenever our Eskimo visitors threatened to eat us out of house and home we could put in a little pinch of salt, and thus husband our resources without seeming inhospitable. A man who tasted anything salty at our table would quickly bethink him that he had plenty of more palatable fare in his own house.
And this is from his book The Fat Of The Land
By the fourth month of my first Eskimo winter I was looking forward to every meal (fresh or high), enjoying them all, and feeling comfortable between times. But I kept thinking the cooked fish would taste better if only I had salt to use with it.
From the beginning of my northern residence I had suffered from the lack of salt. On one of the first few days, with the resourcefulness of a Crusoe, I had decided to make myself a little salt, and had boiled sea water down to where only a brown scum remained. If I had remembered as vividly my freshman chemistry as I did the books about shipwrecked adventurers, I should have known in advance that the sea contains many chemicals other than sodium chloride, among them iodine. The scum tasted bitter rather than salty. A more resourceful chemist could no doubt have refined the product. I gave it up, partly through the persuasion of my host, the English-speaking Roxy
The Mackenzie Eskimos, Roxy told me, believe that what is good for grown people is good for children and enjoyed by them as soon as they get used to it. Accordingly, they teach the use of tobacco when a child is very young. It then grows to maturity with the idea that it can not get along without tobacco. But, said Roxy, the whalers have told that many whites get along without tobacco, and he had himself seen white men who never used it, while of the few white women who had been in this part of the Arctic, wive: of captains, none used tobacco. (This, remember, was in 1906.)
Now Roxy had heard that white people believe salt is good, and even necessary for children; so they begin early to add salt to the baby's food. The white child then would grow up with the same attitude toward salt that an Eskimo child has toward tobacco. However, said Roxy, since the Eskimos were mistaken in thinking tobacco so necessary, may it not be that the white men are equally mistaken about salt? Pursuing the argument, he concluded that the reason why all Eskimos dislike salted food, though all white men like it, is not racial but due to custom. You could, then, break the salt habit with about the same difficulty as the tobacco habit, and you would suffer no ill result beyond the mental discomfort of the first few days or weeks.
Roxy did not know, but I did as an anthropologist, that in pre-Columbian times salt was unknown, or the taste of it disliked and the use of it avoided, through much of North and South America. It may possibly be true that the carnivorous Eskimos, in whose language the word mamaitok, meaning "salty," is synonymous with "evil-tasting," disliked salt more intensely than those Indians who were partly herbivorous. Nevertheless, it is clear that the salt habit spread more slowly through the New World from the Europeans than the tobacco habit through Europe from the Americans. Even today there are considerable areas, for instance in the Amazon basin, where the natives still abhor salt. Not believing that the races differ in their basic natures, I felt inclined to agree with Roxy that the practice of salting food is with us a social inheritance and the belief in its merits, at least to some extent, a mere part of our folklore.
Through this philosophizing I was somewhat reconciled to going without salt; but I was, nevertheless, overjoyed when one day Ovayuak, my new host in the eastern delta, came indoors to say that a dog team was approaching which he believed to be that of Ilavinirk, a man who had worked with whalers and who possessed a can of salt. We went out to receive the visitor and, sure enough, it was Ilavinirk. He was delighted to give me the salt, a half-pound bakingpowder can about half full, which he said he had been carrying around for two or three years, hoping sometime to meet someone who would like it for a present. He seemed almost as pleased to find that I wanted the salt as I was to get it. I sprinkled some on my boiled fish, enjoyed it tremendously, and wrote in my diary that it was the best meal I had had all winter. Then I put the can under my pillow, in the Eskimo way of keeping small and treasured things. But at the next meal I had almost finished eating before I remembered the salt. Apparently, then, my longing for it had been what might be called imaginary. I finished that meal without salt, tried it once or twice during the next few days, and thereafter left it untouched. When we moved camp the salt remained behind.