salt is an essential substance for human survival, and sodium ions and chloride ions contained in salt are very important for human growth and development. Therefore, salt is essential in our human life. Now we can't live without salt for a meal. How did primitive people survive without salt? Don't they need to eat salt? Of course not, because primitive people ate some minerals with salt. The salt we eat now is refined salt that appeared after the industrial development to a certain extent. There are no heavy metal impurities in these salts, which are also very healthy for the human body. First of all, we need to know the role of these salts in our bodies. Salt contains sodium ions, which can keep water balance and acid-base balance in our body. And our cells also need this ion for various life activities. Primitive man is only a stage in the history of human evolution. They also need to eat salt, but they didn't have such refined salt at that time, so primitive people in different regions ate salt in different ways. For example, primitive people living by the sea began to extract salt from seawater. At this time, primitive people have begun to use fire. They will put seawater in a container and then burn it on the fire. This will get the most primitive sea salt. And those primitive people who are far away from the ocean, they will try their best to find one? Mud? . This kind of mud is what we now call a salt field. When primitive people found these salt pans, they found that there was a layer of salty substance like frost on them. This is salt, and primitive people will carefully collect these substances. Then someone asked, what if some primitive people live near the sea and there is no salt field? Primitive people who lived near the sea and had no salt fields obtained salt by preying on prey. We all know that blood contains a lot of salt, so some primitive people will get salt by preying on various prey, drinking their blood and eating their meat. Although it sounds incredible, it can only be done in order to survive.