Injecting Reality into the Alkaline Water for Health (AWH) Trend
Proponents of the alkaline water for health (AWH) trend (a term that I just coined) claim that drinking this ‘miracle liquid’ can increase your energy, prevent disease, slow aging, and prevent bone loss, among other health benefits. The AWH trend has its origin in the claim that most people are walking around with ‘low grade acidosis of the body’ caused by the acidity of many of the processed foods common to a modern diet. They claim that chronic, low grade acidity in the blood and cells is partly responsible for a number of the diseases that plague modern society, like cancer and osteoporosis. Advocates allege that if you drink alkaline water, it can counter this acidity and neutralize your blood and cells – leading to better health and longer life. However, nutrition science and basic biochemistry tell us that this is just plain wrong.
What is alkaline water? It is plain water that is altered so that it has a pH level greater than 7. A pH of 7 is neutral because it is in the middle of the pH scale, where a pH of 1 is extremely acidic and a pH of 10 is extremely alkaline. The normal pH of the human blood is about 7.4; acidosis occurs when body fluids are excessively acidic, and alkalosis occurs when the pH of bodily fluids is too alkaline. When these conditions occur in the human body they are generally caused by serious medical conditions such as diabetes, kidney disease, and various metabolic disorders. People with these issues require more in the way of medical treatment than a different type of water.
So the basic premise of the alkaline water theory is that ingesting alkaline water can change the pH of blood and cells, because the water is alkaline. Why is this theory so far off the mark? Because anything that you swallow goes into your stomach, and in response, the stomach releases digestive enzymes and hydrochloric acid to break down the newly acquired stomach contents. So the pH of the food or drink when it enters the stomach is irrelevant, it all gets acidified. Depending on whether your stomach is full or empty, or the contents of your meal, stomach pH generally ranges from 1 to 3. Then, when the stomach contents are ready to leave for the intestines, the pancreas secretes chemicals which neutralize the acid, so that everything comes out at the proper pH (approximately 8). How, then, is ingesting alkaline water supposed to change this? It can’t. There are no scientific, peer-reviewed studies that show otherwise.
Now, diet CAN change the pH of your urine in either direction on the pH scale because when your body breaks down foods to extract the energy and nutrients, leftovers called ‘ash’ are formed – kind of like what is left over in the fireplace after you burn logs. This leftover ash can be acid, neutral, or alkaline, depending on what the food was made of. Acid-forming ash components are things like phosphate and sulfur, and alkaline-forming ash components are things like calcium, magnesium, and potassium. However, the actual pH of the food isn’t an indication of whether the leftovers will be acidic or alkaline. Oranges, which we associate with being acidic, contain citrate which is metabolized to bicarbonate which is alkaline. Cool, huh?
When the basic leftovers of a digested diet are absorbed by the intestines and transferred to the blood, a healthy person maintains a normal blood pH through some very intricate processes involving chemical buffers in the blood, the exhalation of carbon dioxide (CO2), and the exchange of acids and bases (alkalinizing agents) by the kidneys. This is an extremely complicated process that would require an entire book chapter to explain, so suffice it to say that chemical buffers and breathing out CO2 are more immediate mechanisms to maintain blood pH, where the kidneys do the bulk of the regulation of body pH over time. In fact, it is one of their fundamental roles. Because the kidneys (which produce urine) are constantly working to keep BODY pH in the correct range by balancing the absorption and excretion of acids and bases, urine pH changes constantly throughout the day. This is why urine pH can be affected by the diet or other influences such as exercise and medication use. However, since urine is contained in the bladder and eventually exits the body, its pH doesn’t affect other bodily fluids, and measuring urine pH to determine blood pH does not work.
With respect to nutrition policy, the Food and Drug Administration not only rejects the health claims of alkaline water, but in 2014 issued a consumer warning against false, deceptive, and misleading claims on alkaline water. Dr. Stanley Goldfarb MD of the Hospital of the University of Pennsylvania said it best: “If you drink a lot of alkaline water, all you’re going to do is pee out a huge amount of alkaline material. There really is no rationale for this.”
Water is good for you, it is necessary for life, and most of us don’t drink enough of it. So drink your water, whether it is tap, filtered, bottled, or sparkling and with a spritz of lime – just don’t pay an arm and a leg for a product that doesn’t live up to the alkaline water for health hype.
Image courtesy ofJez Timms / Unsplash.com
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