Why is sweat salty
All humans experience sweating; just some have more of it and some have less of it. Sweating is the method adopted by the human body to keep the body temperature regulated. Sweat is a fluid quite similar in appearance to water. Its generation and then evaporation from the body constitute the process of sweating.
The evaporation of sweat creates a cooling impression because of the property of latent heat of evaporation of water. Sweat is manufactured in the glands near the epidermis in humans and many other mammals. Though the outward appearance of seat drops is pretty uninteresting, the human sweat is actually a complex mixture of minerals, water, urea and lactate. Sodium makes a contribution of about 0.9 gram/liter and calcium follows with a concentration of 0.015 gram/liter. It is worth mentioning here that salt also comprises of two basic constituents – sodium and calcium. The human body also contains a conspicuous amount of sodium which performs many vital functions such as regulating the ideal amount of water inside the cells and the blood stream. Thus, there is a healthy amount of both sodium and calcium in the sweat that appears on our body when we are in a particularly hot environment, or are undergoing any stressful physical exertion. This is precisely why the sweat tastes like the normal table salt we use in cooking. Some people have excess of sodium and calcium content in their bodies and this condition is generally seen in athletes as they are in habit of in-taking salt supplements regularly.
Sweat of such individuals is extremely salty, and there are cases when long distance runners and athletes observe a layer of salt on their bodies after finishing a stressful bout. Salt losses are so common for athletes that this forms a major part of their bodily concerns and they have no alternative to seeking help from external salt intakes. The excess presence of salt in the sweat leads to the problem of hyponatremia. This means less than the ideal sodium content in the blood, and is a matter of alarm.