What Is Alkaline?

Substances Above pH 7

In This Article

The term alkaline is often used to describe blood, water, metals, or a special type of diet. In order to fully understand the term alkaline, you first must consider pH which comes from the term “power of hydrogen,” or the hydrogen ion concentration present in a given solution.

It helps to measure the acidity or alkalinity of a substance. Alkalinity or basicity are alternative terms for the same chemical characteristic.

pH test for alkalinity
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Alkaline Definition

In pure water, a small portion of the molecules lose one hydrogen from the H2O structure, in a process called dissociation. The water thus contains a small number of hydrogen ions, H+, and residual hydroxyl ions, OH-. There is an equilibrium between the constant formation and dissociation of a small percentage of water molecules.

The pH scale runs from 0 to 10. Pure water has a pH of 7, which is considered perfectly neutral. This means that it has exactly equal numbers of hydrogen and hydroxyl ions.

Any substance below 7 on the pH scale is considered acidic and substances that are above 7 on the pH scale are considered basic or alkaline.

How Does a Liquid Turn Alkaline?

Adding a base to pure water makes it become alkaline. In nature, water runs over rocks that contain basic minerals, so the water is often slightly alkaline.

When a base or alkali is added to water it accepts hydrogen ions. By soaking up the hydrogen ions formed by the dissociation of water, the balance of ion concentration shifts in favor of the hydroxyl ion concentration, making the solution alkaline or basic.

Common examples of bases include:

  • Lye (sodium hydroxide): Used in making soap
  • Baking soda (sodium bicarbonate): Used in cooking and antacids
  • Milk of magnesia (magnesium hydroxide): Used in antacids and laxatives
  • Ammonia: Used in cleaning products
  • Borax (sodium borate): Used for cleaning and pest control

What Is Alkaline Water?

Alkaline water is naturally or manmade water that has a pH of up to 8 or 9. Natural alkaline water such as spring water contains minerals that make it more alkaline.

Man-made alkaline water or ionized water goes through a chemical process called electrolysis. An electrical current is sent through the water, separating water molecules into acidic or positively charged ions and basic or negatively charged ions. The positively charged ions are siphoned off, leaving behind alkaline water.

Is Alkaline Water Good for Your Health?

The idea that alkaline water promotes health has been around for decades, based on the idea that the increase in pH of alkaline water neutralizes acidity in the blood, but there is little evidence to support its highly touted health benefits.

Some reported benefits include an ability to boost energy, strengthen bones, or fight cancer, but more research needs to be done to support or refute these claims.

Research on Alkaline Water

No independent research supports the use of alkaline water to fight cancer or boost energy. One major confounder to research on alkaline water is that the studies are often funded by alkaline water companies.

One independent study found that alkaline water with a pH of 8.8 deactivates pepsin, a digestive enzyme found in the stomach, and therefore may be helpful in treating acid reflux.

But it’s impossible to extrapolate what happens in a Petri dish to what happens in the human body. Also, it is unknown how much and for how long one must drink alkaline water to experience this health benefit.

Another preliminary study found that drinking alkaline water plus baking soda may to reduce the concentration of markers of bone breakdown, but these health benefits were seen over a short period of time. More studies need to be done to elucidate the long-term impacts on bone health.

Medical Alkaline Supplementation

Alkaline supplementation is commonly used to correct metabolic acidosis and growth hormone issues.

Severe forms of metabolic acidosis in children, such as renal tubular acidosis, are associated with low levels of growth hormone which results in short stature. In order to correct the imbalance, bicarbonate or potassium citrate is given to increase growth hormone and thereby improve growth.

Alkaline supplementation is sometimes used to offset ion imbalances in people after menopause. Increasing potassium bicarbonate in the diet neutralizes the daily net acid load in people after menopause, which results in a significant increase in growth hormone and osteocalcin.

Finally, some chemotherapeutic drugs have been found to work more effectively in an alkaline environment. In fact, numerous agents such as epirubicin and adriamycin require an alkaline media to be more effective. Still, there is no evidence in the scientific literature that supports the benefit of an alkaline diet for the prevention of cancer.

Is an Alkaline Blood Level Safe?

Life on earth depends on appropriate pH levels in and around living organisms and cells. Human life requires a tightly controlled pH level in the serum of about 7.4, more specifically the slightly alkaline range of 7.35 to 7.45, to survive. 

Having a blood pH that is too high or too low can have serious negative effects on one's life so it is important to consult a healthcare professional before making changes to your regular diet.

Possible Side Effects

Drinking natural alkaline water such as spring water is generally considered safe because it contains natural minerals. Most man-made forms of alkaline water are also safe since water companies generally follow tightly regulated industry standards for healthy water.

Alkaline water is commonly found in grocery stores, health shops, and even small boutiques that sell homemade alkaline water. Even though negative health outcomes are rare, they still occasionally occur.

When to Seek Emergency Care

You may have metabolic alkalosis if you drink alkaline water or consume an alkaline substance and begin to feel symptoms of:

  • Nausea
  • Vomiting
  • Hand tremors
  • Muscle twitching
  • Confusion
  • Numbness or tingling in the face, arms, or legs

If these symptoms occur, call 911 or contact a healthcare professional immediately.

Always exercise caution when drinking artificial alkaline water, as the high pH and artificial contaminants that are contained in the water may do more harm than good.

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  1. Koufman JA, Johnston N. Potential benefits of pH 8.8 alkaline drinking water as an adjunct in the treatment of reflux diseaseAnn Otol Rhinol Laryngol. 2012;121(7):431-434. doi:10.1177/000348941212100702

  2. Burckhardt P. The effect of the alkali load of mineral water on bone metabolism: interventional studies. J Nutr. 2008;138(2):435S-437S. doi:10.1093/jn/138.2.435S

  3. Schwalfenberg GK. The alkaline diet: Is there evidence that an alkaline pH diet benefits health?J Environ Public Health. 2012;2012:727630. doi:10.1155/2012/727630

  4. Waugh A, Grant A. Anatomy and Physiology in Health and Illness. 10th edition. Philadelphia, Pa, USA: Churchill Livingstone Elsevier; 2007.