Why is salt deficiency so serious in Ancient time?

[CheertheSecond]

Salt can be extracted from food and a human body only requires very small amount daily.

Then how did Hyponatremia become so serious in the past?

I don't think with a sufficient diet we even need to add salt into our food these days.

What are the reasons for this problem in the past? Are the living conditions and living habits back then pose as risk factors for Hyponatremia? (More parasites and less hygiene which contribute to many intestinal diseases that cause Hyponatremia? Harder working life which led to loss of electrolyte through sweating and thus cause electrolyte imbalance? Is it because of lack of food that it causes Hyponatremia?)

 

[Crazy_Cat]

Salt trade was controlled in most places and considered high-end and luxury product like spices (what I assume)

 

[CheertheSecond]

Salt trade was controlled in most places and considered high-end and luxury product like spices (what I assume)

The problem of my question is you do not need to eat it to live healthy. You can get it from food.

 

[LilRora]

People's diets were way different a century ago, not to mention millenia ago. Most importantly, products were heavily limited by their origin, as there was no way to transport any perishables over long distances. I'm nowhere near an expert on this, but narrow diets could have easily caused a wide plethora of problems depending on their specifics, likely including hyponatremia.

 

[Nhatduongg]

I think medieval peasants diet consist of mainly grain and not much else, which does that.

 

[ElijahRyne]

Salt can be extracted from food and a human body only requires very small amount daily.

Then how did Hyponatremia become so serious in the past?

I don't think with a sufficient diet we even need to add salt into our food these days.

What are the reasons for this problem in the past? Are the living conditions and living habits back then pose as risk factors for Hyponatremia? (More parasites and less hygiene which contribute to many intestinal diseases that cause Hyponatremia? Harder working life which led to loss of electrolyte through sweating and thus cause electrolyte imbalance? Is it because of lack of food that it causes Hyponatremia?)

The main issue was a lack of iodine in the diet. As for salt, I believe eating a diet of refined grains can lead to a deficiency, but I could be mistaken.