Unlike sugar¹, salt is also necessary in small quantities. It is also quite useful/needed even in moderate quantities (say 1/10 - 1/2 teaspoon) in cases where i

Unlike sugar¹, salt is also necessary in small quantities. It is also quite useful/needed even in moderate quantities (say 1/10 - 1/2 teaspoon) in cases where it got flushed out. For example, you eat too much sugar/saccharides/food for body to process, blood sugar rises and salt is flushed to keep osmotic pressure. After a couple of hours, sugar is spent, you get cravings from falling (normalizing) blood sugar, but you're also hypotonic so you get headaches as your brain is swelling against your skull. Eating/drinking some salt (say 1g), some time after eating, when sugar levels fall (~1-3h) can do wonders. Eating more sugar also relieves the pain, but only by delaying the issue. Of course, not overeating sugar in the first place is even better. ¹ sugar in the sense of mono and disaccharides. Not sure if any saccharides are required in diet.