Like many people, I have often been warned about the dangers of getting too much salt in my diet. While that is a very significant concern for many people, it wasn't until many years later that I was warned about the dangers and symptoms of getting too little salt in my diet. As with so many things, the key is balance - getting the right amount. What you may not realize is that salt is an essential part of hydration and brain functioning. Dehydration is caused by an electrolyte imbalance, which can happen either because you aren't getting enough fluids or you aren't getting enough salt.
When I looked into it, I found out I was chronically not getting enough salt. It may seem weird, but I'm a vegetarian who doesn't eat a lot of junk food and doesn't kike salty snacks. While processed foods tend to be rich in salt (I've seen frozen pizzas or cans of soup that will give you about 2/3 of your salt requirements for the day just from them), natural foods tend to be low in salt, especially vegetarian ones.
The primary warning that you may be low in salt is that you feel thirsty, yet cannot quench your thirst no matter how much water you drink. I found that I would sometimes become so horribly thirsty, but now if that happens and I eat a little bit of salt (it really doesn't take much) and have a small drink, then I stop being thirsty. If you think you may be low in salt, then the first thing to do is to look at the nutrtition information on the foods you eat. They will tell you what percentage of your USRDA the food contains. Try to add it up and see if you're close to the recommended amount. If you are, then you are probably fine, unless it's very hot or you exercise a lot. But you may find, like I did, that you aren't even close to getting the recommended daily allowance. If that's the case, you can try having just a little bit more salt in your diet. It can be good to consult with a doctor before making any significant changes though, and it can be vital if you have any medical issues that may be affected.
Being low in salt can cause you to have less energy, it can cause muscle pains, and it can make it more difficult to think clearly. People who have low blood pressure can be particularly vulnerable to salt deprivation, and can become light-headed. They tend to be more inclined to fainting from dehydration, which can be caused by insufficient salt. At an extreme, being low in salt can be fatal, but people will rarely take it to this extreme. While most people know that they need to replace their salt if it's particularly hot or they are physically exerting themselves a lot, many people don't realize that they also need a basic amount as part of good health. So, while you certainly shouldn't overindulge in salt, do make sure you are getting enough for healthy living.