If you are really low on aldosterone, you can eat salt and your body will not hold on to it. Aldosterone is steroid hormone secreted by the adrenal cortex that regulates the salt and water balance in the body.
I was in the hospital 4 x's is 7 months with my sodium level being the lowest 119 when it should be (136-146). And I ate and ate salt and salty foods and even drank salt water and I could not hold the salt, I had to be put on fludrocortisone and at this time I am still on it..on it since 1/10.
I believe through and electrolyte blood test they can tell were your sodium level is...Big sign of low sodium in most people is if you crave salt.
Some of my symptoms of low sodium:
burning stomach-lower leg weakness (could not walk for 4 days when it was at 119)-dizziness-pains in my arms and numbness in fingers and toes, when I would stretch my foot out the foot would lock and hurt like -ell.- exhaustion and restless legs while trying to sleep.