pH Quackery and Human Acid-Base Homeostasis
Note: TV4 has since removed the clip, possibly because of embarrassment. It is no longer available online (note added 2012-09-07 22:52 DST).
An incredibly pseudoscientific set of medical claim was broadcasted on Sweden television (TV4) yesterday: pH quackery. The interviewed guests proposed that “having a basic body” is a universal cure for tiredness, stiffness, allergies, migraines and other miscellaneous problems. Sadly, they fail miserably at basic (no pun intended) human physiology. Enzymes and other proteins in the body depend on keeping the pH-level roughly constant. Otherwise they can loose their three-dimensional structure, and therefore function. This would be very dangerous to us. However, the human body have a robust system for regulation body pH to maintain it within physiologically optimal levels and only serious medical conditions can upset this balance, which is called acid-base homeostasis (Sherwood, Klandorf och Yancey, 2005, s. 599-603):
(1) Bicarbonate buffer system:: a chemical equilibrium with carbon dioxide on one side and hydrogen ions on the other (and some additional components, se below) If the concentrations of hydrogen ions increase, the equilibrium will be shifted towards producing more carbon dioxide in accordance with Le Chatelier’s principle). This carbon dioxide can be exhaled.
(2) Proteins: proteins usually have both a positive and negative charge, so they can bind or release hydrogen ions depending on pH.
(3) Hemoglobin in RBCs: when hemoglobin releases oxygen in an acidic environment with lots of carbon dioxide, it has a higher affinity for hydrogen ions and some become bound. These bound hydrogen ions no longer contribute to blood pH. Near the lungs, these hydrogen ions are released and combine with carbonate ions to form carbon dioxide, which are exhaled.
(4) Phosphate buffering: reminiscent of the bicarbonate buffer system, but has disodium hydrogen phosphate and hydrogen ions on one side of the equilibrium and sodium hydrogen phosphatase and sodium ions on the other.
(5) Renal regulation: kidneys can excrete both hydrogen and carbonate ions to regulate pH.
So in summary conclusion, the human body has a robust way to maintain inner pH at a constant and physiologically optimal level. Average foodstuff you eat do not upset this balance in any pathological way.
Let us look at the specific claims being made in the TV clip (my translation). Three people are being interviewed. Gertrud Ruslander is the elder lady in gray hair on the left, Sara Karlsson is the younger female in the center and Ragnar Rylander, emeritus professor in environmental medicine, sits to the right.
The definition of pH
TV host: So if we begin with you, Sara, what actually is the pH-value?
Sara Karlsson: To make it simple, it is hydrogen density. pH means hydrogen density. It is how much hydrogen one have, actually in relation to oxygen. So the more hydrogen, the more acidic you are and the more oxygen you have, the more basic you are.
Sara Karlsson makes a flawed attempt at defining pH. In reality, pH is a measure of the concentration of hydrogen ions. The lower the pH, the higher the hydrogen ion concentration. It has nothing to do with hydrogen density, how much hydrogen you have in your body per se or the ratio of hydrogen to oxygen. I suspect she is trying to describe the bicarbonate buffering system while conflating high levels of carbon dioxide from high acidity with low levels of oxygen:
Becoming more basic?
TV host: What do you do to become more basic? Tell me about that.
Sara Karlsson: Actually, it is about adding oxygen to large portions of your body and the most natural is lime, which we would get into our bodies through the water and it does not exist anymore. It is acidified..the environment is acidified and we take in too much…through the air and through bad food or chemicals and all of that stuff that effects the body. This is actually very new, because for 100 years ago, maybe it was enough to change diet to become really healthy. There are those that become really healthy from changing over to a vegan diet, for example. But today, it is almost never enough and diseases emerge at younger and younger ages. Adult-onset diabetes that you got when you where fifty before, you get today when you are three or four years old.
If you exhale carbon dioxide, you reduce pH levels in the blood by means of the bicarbonate buffer system. So far, so good. Lime can contain carbonate ions, but I doubt that you need to consume special quantities of lime in the drinking water is necessary. Like any supplements, it is probably enough to eat a varied diet.
Sara Karlsson also underestimates the power of the acid-base homeostasis in the human body. She appears to think that human pH just floats with external pH and the pH of items we consume or inhale. This, as we have seen, is not so.
Also, “chemicals” is a word that just refers to chemical compounds. Every time you drink pure water, you are drinking a chemical. Every time you eat wholewheat or brown rice, you are consuming a mountain of different chemicals. The relevant factor is therefore not if something is a chemical, but if it is a chemical hazardous to human health in the concentrations being consumed.
The connection made to type 2 diabetes is completely irrelevant. The increase in early-onset of type 2 diabetes is due to increased obesity and lack of physical exercise among young children and teenagers (Alberti et. al. 2004).
Misunderstanding the bicarbonate buffer system
TV host: Why is this? Because we are living in a different way and that this bank that existed before no longer exists?
Sara Karlsson: Exactly. We are born with a carbonate buffer, as it is called. It is an acid buffer that is suppose to take all of these toxins and acids. This is the most basal stuff for all humans. If you look at oxygen, it is breathing. In with oxygen, out with acids.
The bicarbonate buffer has nothing to do with “toxins”. It is a buffer that helps regulate pH in our bodies. The acids are not breathed out. As we breathe out carbon dioxide, the chemical equilibrium shifts towards producing more carbon dioxide (consuming hydrogen ions in the process), which we exhale.
The parade of anecdotal evidence
The TV host turns to Gertrud Ruslander. Ruslander says that she started getting menstrual cramps and migraines at the age of 12. She complains that the health care system just gave her pills. At the age of 50, someone told her to try something “alternative”. She says that people are adding lime to the environment outside, but never to our bodies. This is of course a confused argument: the body has many different systems for regulating internal pH, which cannot be found in the environment, or at least not to the same extent. So the analogy fails.
She spews out a long list of medical conditions she claims to have had: sensitivity to light, sensitivity to sound, clinical depression, dizziness, problems concentrating, broken collarbone, broken pinky and constant migraine etc. She also complains that when doctors hear “old lady” and “pain”, they just give her pills. Apparently, after starting to eat teaspoons of lime and various vitamin supplements, she was cured of all of these problems and have never had any issues in the last 25 years.
Needless to say, the emphasis of anecdotal evidence instead of research and the cure-all claim should make us skeptical, to say the least.
The interview moves on with Ragnar Rylander.
Significance and sample size
TV Host: Men Ragnar Rylander, when you do research in this area, how does the health care establishment view what Gertrud is telling us about?
Ragnar Rylander: It is a bit complicated because…the knowledge about acid/base is pretty old. There was a very successful doctor in Sweden in the 1930s that worked with this, Gunnar Berg, but for some reason the idea, the concept, has not been transferred to practical care. There are many studies that support what was told before, that you can cure the symptom of migraine, join pain and other types of disease, but it has never gotten a breakthrough in the health care system. I suspect that there are too few large studies. To be convinced, you need a study of 2000 and it is not enough to, like me, do studies of thirty or forty people. Even if it is significant, they say “no, we need larger studies, more people” and in the absence of this, one does not change from this pill orientated care we heard about before.
Do tell Rylander, what are these studies?
In general, Rylander does not seem to understand why sample size needs to be larger than 30 or 40 people to justify a radical change in the health care system or why significant results are not enough. I discussed this in greater detail in my post Butchering Scientific Studies. A large sample size is needed to (1) avoid the large effects of randomness on outcomes and (2) ensure that the efficacy of a treatment is more representative for the population. Merely statistical significance is not enough, because that only tells you how likely the results, or more extreme results, are given that the null hypothesis is true. It tells you nothing about the effect size (how large the effect is) or about its practical significance (is it large enough in the biological context to justify radically altering health care protocols)?
When they attempt to recommend a pH diet, they suggest that proteins acidify the body and should be avoided if not compensated by vegetables or eating lime. This is pretty ironic seeing how proteins are excellent regulators of pH, as we saw above.
References and further reading
Alberti, G., Zimmet, P., Shaw, J., Bloomgarden, Z., Kaufman, F., & Silink, M. (2004). Type 2 Diabetes in the Young: The Evolving Epidemic. Diabetes Care, 27(7), 1798-1811.
Sherwood, L., Klandorf, H. & Yancey, P. H. (2005). Animal Physiology: From Genes to Organisms. Belmont, CA: Brooks/Cole.
Mirkin, G. (2009). Acid/Alkaline Theory of Disease Is Nonsense. Quackwatch. Accessed: 2012-08-20.
Novella, S. (2008). Body PH Quackery. The Rogues Gallery: The Official Blog of the Skeptics Guide to the Universe. Accessed: 2012-08-20.
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