What is pH and Why is it Important?

pH is the abbreviation for the term "Hydrogen Potential", and is used to indicate the acidity or alkalinity (base) of a substance or compound as ranked on a scale from 1.0 to 14.0. Alkalinity increases as the pH value increases and acidity increases as the pH value decreases. See the graphic below for the pH of some common fluids.

The pH scale measures the logarithmic concentration of hydrogen (H+) and hydroxide (OH-) ions, which make up water (H+) + (OH-) = (H2O). When both types of ions are in equal concentration, the pH is 7.0 or neutral. Below 7.0, the water is acidic (there are more hydrogen ions than hydroxide ions). When the pH is above 7.0, the water is alkaline (there are more hydroxide ions than hydrogen ions). Since the scale is logarithmic, a change in the pH by 1.0 unit is equivalent to a 10-fold increase in acidity. So, a water sample with a pH of 6.0 is 10 times as acidic as one with a pH of 7.0, and pH 4.0 is 100 times as acidic as pH 6.0. For comparison of liquids found in everyday life: beer with a pH 4.5 is 100 times more acidic than natural spring water with a pH 7.5.

Role of pH in Digestion and Illness

Stomach acid and digestion takes place at a very low pH. Most foods are acidic and human physiology is geared towards handling a mostly acidic diet. The enzymes that process digestion are activated by low pH. Alkaline adjustments to the body would only be recommended in the case of an overly acidic stomach as adivsed by a physician. Furthermore people who consistently ingest antacid tablets beyond what is needed will experience a decrease in their stomach acid's function in killing food born pathogens. This is because the strong alkalinity of these medicines neutralizes the highly acidic and sometimes bothersome stomach acid, which kills food borne bacteria. Normal stomach acid plays an important function in defending the human body against illness.

High pH or Alkaline Water

Water has very limited ability to buffer against changes in pH. Increases in pH to 9-12 range require very little added base. For example our Home Master Artesian Full Contact is able to effect a full 1-2 point change in pH with only 30-60 mg/L of added calcium and magnesium. Although there are those who feel that drinking alkaline water is healthy, there are no proven medical benefits, beyond those associated with hydration / drinking water in general. While alkaline water can neutralize no more than 1 mEq of acid (HCl) - Antacids, which are given to neutralize gastric acid, are capable of neutralizing at least 10 mEq of acid, and contain far more calcium.

Document sources: US EPA; Jacobson, Tilbury, Lantz, Nix, University of Arizona Center for Toxicology

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