My friend recently bought a water filter. It's purpose is to raise the tap water's pH-level to alkaline level... She claims that alkaline water is good for our body because it reduces our acid level in our body. Is it true that waters with high alkaline (pH) level really healthy for human body? She paid $1000 for this water filter. Is it worth it? Please let me know soon if it's actually good for me, I'm thinking of purchasing one.

Dear Reader,

Filtered water seems to be all the rage these days – your friend is not alone in her enthusiasm for filters like Alkazone. However, any product that claims to change the body's acid/alkaline balance in any substantial way is not based on sound science. Significantly changing the pH balance in your body is virtually impossible, and actually not desirable.

A normal pH, the measure of acidity vs. alkalinity, is carefully monitored by various body systems to stay between 7.35 and 7.45. This is slightly on the alkaline side of neutral (7 on a scale of 1-14). Activities like changing your respiration rate or eating different foods impact the pH slightly, but the body quickly compensates, mainly by releasing neutralizing agents into the bloodstream or changing the acidity level of your urine. If your blood starts to become too acidic, the kidneys will quickly compensate by releasing more acid into the urine. Similarly, if the alkaline level rises above normal, your kidneys will release more basic solution into the urine. Because urine is held apart from the rest of the body fluids  and soon excreted, the body can maintain a stable pH by adjusting the pH of the urine, then getting rid of it.

Although claims have been made that a diet high in alkaline food or water will slow down the aging process or inhibit the growth of cancer cells, there is no human research to support this. Cancer cells may die in a test tube environment more alkaline than the normal body, but healthy cells cannot survive in that kind of environment either. So reducing acid levels in the body might kill cancer cells, but it would likely kill the rest of your cells too. In addition, important chemical reactions such as those involved in digestion can only take place within the normal 7.35-7.45 range.  That is why the body so carefully moderates its own acid/alkaline balance.

Therefore, even consuming large quantities of acidic or alkaline foods or water, or taking antacid tablets, or holding your breath for 5 minutes will not change the overall pH of your body, nor would one want it to. The water filter's claims are most likely bogus. That may leave you with $1000 of extra cash! Toast to that! With pure (filtered) water of course…

Alice

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