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Life Sciences => Physiology & Medicine => Topic started by: DrCuriosity on 08/11/2013 21:53:01

Title: Does chronic excessive water drinking cause accumulative effects on blood pres.?
Post by: DrCuriosity on 08/11/2013 21:53:01

I read some literature saying drinking water do have acute effects on blood pressure and heart rate, especially for people with damaged autonomic nervous system. But, for a longer term, if a healthy person continuously drinks more water than he should, does it have great influence on the regulation of blood pressure?

I am an engineering researcher trying to simulate water intake effects on cardiovascular system parameters based on system-level simulations. I am not quite familiar with physiological studies or clinical research on this topic... Just wondering if there is any clinical observation or common facts related to this question. Thanks!

Title: Re: Does chronic excessive water drinking cause accumulative effects on blood pres.?
Post by: CliffordK on 08/11/2013 22:03:50

You may read about water intoxication (https://en.wikipedia.org/wiki/Water_intoxication). 

Apparently it involves drinking more than one can excrete with urine, and thus diluting the blood which then causes fluid to enter into the cells.  While much of the body may be able to compensate, swelling in the brain can be detrimental.   

Title: Re: Does chronic excessive water drinking cause accumulative effects on blood pres.?
Post by: DrCuriosity on 08/11/2013 22:45:59

Quote from: CliffordK on 08/11/2013 22:03:50

You may read about water intoxication (https://en.wikipedia.org/wiki/Water_intoxication). 

Apparently it involves drinking more than one can excrete with urine, and thus diluting the blood which then causes fluid to enter into the cells.  While much of the body may be able to compensate, swelling in the brain can be detrimental.

Thanks for your answer, CliffordK.

I know if one drinks too much water, one will get water-intoxicated. Here I am considering "moderately" excessive water drinking. for example, if one thinks water drinking is good for health, and he/she intentionally drinks double the amount of water everyday. Does this affect his/her blood pressure regulation on a long term basis? Particularly, if he/she has once had cardiovascular disease.

Well... this maybe a quite vague question depending on this person's particular situation... I am just wondering if there is some clinical evidences.

Title: Re: Does chronic excessive water drinking cause accumulative effects on blood pres.?
Post by: CliffordK on 09/11/2013 02:27:25

Certainly you could look. 

However, if the kidneys are functioning properly, they should be able to regulate the body fluid volume whether you drink a quart of water a day or a gallon or two of water a day.  Perhaps you could get a transient volume overload shortly after drinking a 44 or 64 oz drink (double gulp (http://www.theatlanticwire.com/national/2012/06/7-eleven-downsizes-double-gulp-just-156-your-stomachs-capacity/53538/) (they shrunk [:(])).

Your arterial system is muscular, and can contract and relax to regulate blood volume and pressure (which is often a target of blood pressure meds).

The kidneys also regulate salt, so low salt diets can help a bit, but if the kidneys are good, the gains from a low salt diet can be very minimal.

I think there is a risk of athletes developing hyponatremia (https://en.wikipedia.org/wiki/Hyponatremia) with a very low salt intake.  It is rare for healthy non-athletes.  Here is an interesting article about hypotonic sports drinks and hyponatremia (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2577547/).