Much has been made by those in the natural health arena about the importance of balancing the pH of the body through diet and sometimes through the use of various products. Unfortunately, much of the information in this area is extremely confusing and misleading. Although the dietary recommendations made on the basis of balancing pH or reducing the acidity of the body are generally good, in my opinion the benefits of these dietary recommendations don’t really have that much to do with the pH of the foods/products being acidic or alkaline.
Before I go into that though, I think a few points of clarification are in order. First, the relative acidity or alkalinity of a substance is measured as its pH (which stands for “potential of hydrogen” – a chemical term that refers to the fact that acids typically interact with other substances through their hydrogen atoms). The pH scale ranges from 0 (extremely acidic) to 14 (extremely alkaline). A substance with a pH of 7 is completely neutral.
While most people know that strong acids can produce damage, they may not be as familiar with the damage that can be caused by strongly alkaline substances. One example of a strongly alkaline substance is drain cleaner, which a lot of people think is an acid. So, the acidity or alkalinity of a substance does not make it good or bad, it’s just an indicator of its chemical nature.
The next point of clarification that is needed is that when nutritionists or people in the natural health field talk about acidic or alkaline diets, they are referring to the effect of a given food or diet on the body’s pH – most commonly measured through the urine (and sometimes saliva and/or blood). The acidity or alkalinity of the food itself has NOTHING to do with whether or not it causes the body to become more acidic or alkaline. So, foods that are themselves acidic, in the process of being digested and absorbed by the body, may cause the body (urine) to become more alkaline, and vice-versa. This is a common source of confusion.
Now that we have those issues out of the way, the next thing to discuss is the body’s buffer systems. The body has several mechanisms it can use to vary the pH of the blood. One reason why blood pH is important is because if it gets too acidic, the blood cells begin to clump together and become much less efficient at carrying oxygen, and much more likely to get stuck in blood vessels and result in circulation problems. So the body has systems to monitor and buffer the acidity of the blood. The details of how each of these systems works would fill an entire physiology textbook, so I’m not going to discuss the mechanisms here, but the major buffering systems include the respiratory system, the skeletal system, and the urinary system.
Of those buffering systems, I do want to briefly discuss the urinary system. Earlier I said that body pH is often measured through the urine. When the blood becomes too acidic, the kidneys transfer part of the excess acid from the blood to the urine. So, excessively acidic urine is an indicator that the blood is too acidic – or at least was temporarily.
With the exception of the buffering that the body does through respiration, the buffer systems use various minerals to alter the relative acidity or alkalinity of the body. Herein lies my primary issue with the acid versus alkaline diet concept.
It so happens that foods that fall under the highly-touted “alkaline diet” tend to be high in nutrients that the body uses to buffer acidity, as well as have numerous other beneficial effects. As stated earlier, this has NOTHING to do with the pH of the foods themselves. In fact, some of the most acidic foods you can eat (apples, citrus fruits, etc.) are some of the best at producing a more alkaline environment in the blood. Basically, the “alkaline diet” consists primarily of vegetables and fruits. Foods that promote acidity in the blood are primarily the protein foods (beef, eggs, poultry, pork, and fish) and grains. But once more, this has nothing to do with the relative acidity or alkalinity of the foods themselves, only their nutrient content.
As I said, the contribution of buffering nutrients from the alkaline diet foods is only part of their health benefits. Those same foods are a great source of anti-oxidants like vitamin C. Many are good sources of minerals like potassium and magnesium necessary for normal heart and muscle function. Most are good sources of fiber and enzymes that are important for normal digestive function. So these foods are beneficial in numerous ways and I think to get hung up on the acidity/alkalinity aspect is a mistake.
Why do I think this is a mistake? Because of the confusion in labeling a food as “acidic” or “alkaline”. If an acidic food is considered alkaline and a more alkaline food (very few foods are actually alkaline themselves – almost all foods have a pH of less than 7, which by definition makes them acidic) is considered acidic, how is the average person supposed to make sense of that? All that the alkaline diet promoters are doing is making something very simple extremely complicated.
Most people these days know that a diet high in fresh vegetables and fruit is healthier than a diet high in junk food. Wouldn’t it suffice to just advise people to eat a diet high in fresh vegetables and fruit and to minimize their intake of processed foods, animal proteins, and grains? Is calling that an “alkaline diet” going to make anyone more or less likely to follow it?
So if the “alkaline diet” is simply an over-complication of basic, healthy diet recommendations, how did this concept get so popular? My theory is that it developed as a marketing scheme for various products that are sold to “alkalinize the body”. After all, the average person knows that acid is dangerous, so they took the concept that people already had that acid was dangerous and used it to sell health products.
The other aspect of it is that because the acid/alkaline balance issue is so confusing and complicated that most people need a health care provider to advise them on it. I mean, if you pay good money to see a health care provider and he or she just told you to “eat your vegetables”, you might be a bit disappointed since your mom has probably been telling you that since you were a kid! So the health care provider needs to look smart, and one way to do that is to make something really simple and common-sense seem very complex.
So, is the alkaline diet bad? No, in fact it is a very healthy way of eating. My objection to it is the name. A healthy diet has nothing to do with whether the foods you eat are acidic or alkaline. A healthy diet has to do with getting the necessary nutrients so that your body can propely manage all of its functions, including maintaining normal pH.