water retention and sodium?

Question

i know excess sodium in our body causes water retention.excess sodium i know can be eliminated through sweat,diarrhea and urine.i have a doubt.does tears from our eyes contain sodium?does it also eliminate excess sodium from our body?

Answer 1

There probably is a very small amount of Sodium in tears-(140 meq/liter) but since our "tear" out put per day is so minute
( less than 30 cc - 1 oz) we probably excrete less than 5 meq per day from our tears. (Also most of our tears are reabsorbed back into the conjuntivae)
With urine- we have special hormones (Atrial Naturetic Hormone (ANF) and Aldosterone ) that regulate Sodium excretion through the kidneys.
Since the average adult makes over 2 liters of urine/ day, our kidneys are a lot more efficient at getting rid of Sodium in our urine.
Unfortunately, the human body was developed to more efficiently reabsorb sodium than to excrete sodium (more stimulators for Aldosterone than ANF), that is why many people have problems with edema and ankle swelling.

Its an interesting question, but to answer it- one needs to know how the kidneys work. And since tears are not under hormonal regulation, and so little tears are lost -compared to other fluids -they are not a useful mechanism for the body to get rid of Sodium.

I hope that this explanation is understandable. I am a Nephrologist.

Answer 2

Tears taste salty because of the sodium and other ions that it contains. You could reduce excess sodium though crying if you had the ability to cry buckets of tears. Maybe rivers of tears. You can get rid of more salt by just laying off the french fries.

Answer 3

Tears do contain sodium. However, since the volume of tears is so small, you won't lose much in fluid by crying. Urinating is the best way (and the body's most natural way) of removing toxins from the body.

Answer 4

All body fluids, including tears, contain sodium but if you're looking to reduce overall sodium levels through tears,,,,,

You'd really have to 'Cry me a river'....