Advice - to RO or not to RO

[Ed4567]

Sorry if I'm going completly wrong here but anyway...

The water has NOTHING in it so SOMETHING must fill it. Regular tap water has all kinds of stuff in it, most of it nonnutritious but it's there so there's little need of equilibrium

As I said above diffusion occurs independantly for each type of molecule, the 'non-nutritious' stuff has absolutly no effect on the diffusion of vitamins or other minerals.

 

[Ed4567]

Should have added to the last post:

Therefore both pure water and tap water (not already containing the vitamin) will 'take in' the same amount of the vitamin from the body.

Maybe purified water does 'remove' some substances from the body, but then considering the impurites in tap water tend to be at a much lower concentration than those consumed in food, to me this seems unlikely.

 

[Ed4567]

Done a bit of searching on this:
http/reefcentral.com/forums/showthread.p...er&pagenumber=1
(you have to be a member so I'll copy the main couple of posts:

There is nothing wrong with RO or RO/DI water for drinking. Your body is very adept at maintaining osmotic equilium in the setting of hypo and hypertonic fluids. The primary components that make up serum osmolality are sodium, glucose, and blood urea nitrogen (which can be roughly estimated by Na x 2 + BUN/2.8 + glucose/18). Serum oncotic pressure is also maintained by blood protein, primarily albumin. None of these things are found in great quantity in tap water or RO/DI. It just tastes different because of the lack of contaminants normally found in tap water. Most of the trace elements and ions you get from your diet, not drinking water.

You can cause electrolyte imbalance by drinking enough RO/DI or tap water alone (called psychologic polydipsia, which is rare but usually seen in schizophrenics and others with mental illness.) And I'm talking gallons of excess water a day. You simply overload your kidneys ability to get rid of the hypoosmolar solution and eventually your sodium drops too low and you seize (typically when it hits less than 120 MeQ/dl - normal is 135 -145). In contrast this can happen inadvertently in newborns just by giving them as little as 8-12oz of tap water a day for several days due to their relative body surface area (which is why newborns should only receive formula or breast milk.)

Ok, now that I have bored everyone silly with this long winded explanation, the bottom line is RO/DI is just as safe as tap water, as long as you drink it to match your daily requirements. Any ions, minerals, etc that have been removed you will easily replace by eating. The only thing that you might not be getting enough of is flouride, but as long as you brush your teeth you will be fine. Just be careful with the kids since flouride in municipal water has been shown to reduce cavities in children, and they don't brush like they should. So drink up!

From the same person:

I am a pediatrician and I work in a molecular biology research lab. As I said above, water is primarily meant to maintain blood volume. Even if you get pretty dehydrated the electrolyte balance in your body stays pretty stable. By the same token, if you drink a lot of pure water (with no minerals, electrolytes, etc.) you will simply pee out the extra free water and your electrolytes wouldn't budge an inch. So don't worry, this stuff is perfectly safe (RO or RO/DI.)

And from an analytical chemist and lab director:

This thread should have it's own forum as it appears monthly and always has many contributors. Between the calcium being depleted from one's bones to people bursting from osmotic shock it is a classic.

RO units have been used for years for drinking water purposes. From under the counter units to massive million gallon per day plants it is a method that is recognized by EPA, AWWA, NSF and a host of other American and World health organizations. The greatest use is for de-salinization but it is also used to treat difficult supplies that would otherwise be unfit to drink. The main reason it is not more widely used is that it is wasteful when used on a large scale. The reject water loss outweighs the benefits of the output quality.

DI is a grey area. There is no known harm from drinking DI but there is also no demand because of the cost of treatment. This means there has been almost no attempt in the water treatment industry to promote its use. Of course, in an off hand way millions of people drink its close cousin sodium exchanged (demineralized) treated water form either home units or municipal supplies. Except for the added sodium in such water, there have been no health related issues. Drinking DI would even eliminate the sodium problem, but again, cost is the factor and DI would cost more than sodium exchange as the sulfuric acid and sodium hydroxide used as the regenerants cost more than salt. Also, these regenerant's disposal is somewhat more involved.

In many cases the difference between RO and RO/DI is merely one part per million of dissolved solids. If one ppm less does anything bad to one's body it is news to me.

Anyway I've been drinking it for years---which probably explains why people consider me strange.

 

[mlee0332]

I agree with ed. For example: Salt diffusion. Salt will diffuse thru the membrane of a cell until it reaches equillibrium, regardless of what else is in it's destination. BUT, thanx to semipermeable membranes, only certain things can pass in/out. If the cell NEEDS it, it will allow it in, and when its thru using it, it allows it out as waste. That said, the unhealthy stuff wont be allowed into the cell, unless it can use it in some way for energy, and the things that it is using wont be allowed out, until it is waste. So the good minerals we get from water, and food mostly, will be kept inside the cell.

Now what you are saying would be true if the membrane was permeable.

 

[bunjiweb]

An R.O. Filter is certainly worth it. They can lower the pH because they filter metals / minerals that can make the pH more alkali. (sorry if this has already been mentioned).
I have been contemplating in getting one myself, Although I am not sure where I could possibly put it...

Ben

 

[Def]

Ed, very interesting. I've changed my opinion now, based on that.

FWIW, I've even seen R/O units labelled with "do not use for drinking water"...