h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

We all know salt is bad for you, but is it the sodium itself, or the salt?

I ask because I also use MSG and Sweetex pills (sodium saccharin) and probably ought to cut down on all of them...

Hi DaveBlackeye,

It's all sodium, I'm afraid. My mom's on the Mayo Clinic's lower sodium DASH diet, to control blood pressure, and she carefully tracks all sodium intake.

Here's a link: http://www.mayoclinic.com/health/dash-diet/HI00047




HN

Firstly, there is no documented evidence that salt is actually bad for you. There is an awful lot of quack science about blood pressure, hypertension and the like, founded on rudimentary knowledge of diffusion, and a lot of tenuous theories about heart disease with no actually supporting fact. The human body has an exceedingly effective method for disposing of excess salt, assuming you have functional kidneys. In fact, the kidneys are the most likely part of you to expire from excess salt, simply because they are being forced to do more work.

Asking whether 'salt or just sodium' is to blame is opening up a whole raft of chemistry. Sodium ions are a constituent part of table salt and completely dissimilar (macroscopically, at least) to sodium metal. There are a virtually infinite number of other salts, very few of which you would wish to go anywhere near your body. Arsenious chloride in your soup, anyone? The question is so ill-phrased as to be effectively pointless.

B

i had high blood pressure as a young man, i cut out execess salt and my blood pressure returned to normal

Okay, Mu Beta, you have a point. I did not inform DaveBlackeye of the difference between elemental sodium and the sodium ion in sodium chloride (table salt). I didn't imagine for an instant that he was proposing to use elemental sodium or arsenious chloride as condiments - possibly this shows a lack of imagination on my part. Finally I did not point out that the "salt = bad" was a sweeping generalization. This is the SEx forum, and I shall endeavor to be more specific in the future.

DaveBlackeye, salt (sodium chloride) is not necessarily bad. In fact, a little sodium is necessary for your body to function properly. But how much is enough, and how much is too much?

The National Academy of Sciences' Institute of Medicine has recommended not exceeding the range of 1,500 and 2,400 milligrams (mg) a day for healthy adults. Healthy adults with healthy kidneys are indeed able to excrete excess sodium as Mu Beta pointed out.

When the kidneys' ability to excrete sodium has been exceeded, the sodium starts to build up in the blood. Since sodium attracts and holds water, the blood volume increases. The heart then must work harder to move the greater blood volume. A number of health conditions, including chronic high blood pressure, can damage the kidneys upon which sodium excretion depends.

http://kidney.niddk.nih.gov/kudiseases/pubs/highblood/#how
National Institute of Diabetes and Digestive and Kidney Diseases

The sodium in sodium chloride is the same kind of sodium in monosodium glutamate (MSG) and in sodium saccharin. These sources of sodium, as well as the sodium naturally occurring in foods, all count toward the 1,500 to 2,400 milligrams per day for healthy adults.

Disclaimer: If you have a health concern, consult your doctor and not internet weirdos like me.


HN

"The question is so ill-phrased as to be effectively pointless."

In that case, well done MB for using so many words to utterly fail to answer it. I thought the title might've hinted that I was not seeking a GCSE chemistry lesson. Forgive me; I will endeavour to phrase my biology questions in such a way that chemists can understand them in future .

Happy Nerd - thank you , for both providing the answer I was looking for and seeing the irony. I need to keep tabs on all the sodium, not just the NaCl.