Alkaline Water – Debunking the Health Fad with Chemistry

By Samantha Stadmiller

A quick Google search of alkaline and you will likely find a sea of conflicting information about alkaline diets and alkaline water. Alkaline seems to be the new buzzword, but with all the contradicting information, it is hard to discern fact from fiction.

There are many claims out there that alkaline water is “good for your health”, “detoxifying”, and “energizing”. Many of these claims stem from the belief that an unhealthy body is acidic, therefore eating and drinking alkalizing foods can alter your body’s pH, make you healthier, and treat certain illnesses. There is little evidence to support these claims and there are many misconceptions about alkaline water. Here are five simple lessons from chemistry to explain the facts about alkaline water.

1.   Alkaline just means a pH above 7. Before even addressing the term alkaline, it is important to understand the concept of pH. pH is simply a scale for measuring the amount of hydrogen ions in a water-based (or aqueous) solution. So water that is described as alkaline just means that it has a pH that is greater than 7. There are many bottles of water marketed as alkaline and this just means the pH is somewhere between 7 to 14. Pure water on its own (at room temperature) has a pH of 7, no exceptions. For water to be either alkaline or acidic it must contain something else, which brings us to chemistry lesson 2.
2.   Alkaline water consists of water and other ions. Ions are simply charged molecules, which are charged because they have more or less electrons than their neutral compounds. Some common ions that are found in water include: calcium (Ca2+), magnesium (Mg2+), sodium (Na+), potassium (K+), bicarbonate (HCO3-), chloride (Cl-), and sulfate (SO42-). The positively charged ions are called cations while those negatively charged ions are called anions. Ionic compounds, often called salts, are commonly found as a cation-anion pair. These salts can be acidic, basic (alkaline), or neutral and therefore the pH of water containing the dissolved salts is dependent on the acidity or basicity of the salts present.
3. No two alkaline waters are the same, meaning their chemical compositions are not identical. Whether bottled or from the tap, alkaline water contains a variety of dissolved ions. If tap water is alkaline, it is because it picked up these ions from the Earth, your local water treatment facility, or the pipes. The chemical composition of tap water is therefore dependent on these variables. Bottled water that is labeled as alkaline is usually made by adding compounds, often basic salts, to increase the pH. A quick look at the ingredients label of a popular alkaline bottled water, that advertises a pH of 9.5, shows that it contains sodium bicarbonate, dipotassium phosphate, magnesium sulfate, and calcium chloride. Bicarbonates, sulfates, and some phosphates are basic ions, which contribute to the alkalinity of the water.
4.   Alkaline ionized water is not antioxidant-rich. You may have also heard claims that alkaline ionized water has miraculous antioxidant properties. Water ionizers work through a process called electrolysis, which is the breakdown of compounds by application of an electric current. The result of electrolysis on normal tap water is a solution that can have increased concentrations of particular ions and contaminants and can also have a composition similar to diluted bleach.The compound that makes the water similar to bleach is sodium hypochlorite, which is an oxidizing agent, not an antioxidant.
5.   Your body is already really good at maintaining pH. There still is a debate over whether diet can alter your overall body’s pH despite the lack of evidence to support it. Your body’s metabolism is highly complex and the body has elaborate machinery for maintaining the pH within a variety of tissues. This is because the proteins and enzymes that carry out biochemical reactions in your body require a particular temperature and pH to function properly. Your body also contains multiple buffers, or solutions that resist changes in pH, which helps keep the pH at its optimal level. Your stomach, for example, has an acidic pH of 1.5-3.5. This means that if your drink alkaline water, it will immediately be neutralized by the gastric acid in your stomach. Bottom line, food and drink cannot significantly alter your body’s pH.

Alkaline water, a health fad that marketers have taken advantage of to make a profit with sparse to non-existent scientific studies to back the miraculous health claims. At the end of the day, you need to stay hydrated, so drink your water, but don’t fret over the pH and don’t be fooled by the expensive gimmicks.

Peer-reviewed by Ruixue Hou