A common view on health, especially in Asian cultures, is that the root cause of maladies and diseases, especially cancer, is from an “acidic” body type, and that the key to good health and longevity is to achieve an “alkaline” body type through diet. This is often shared and spread on social media without second thought.
There are entire industries devoted to making products, such as alkaline water, based on this concept, along with countless internet memes and articles.
This view has been popularized by a Japanese doctor, who allegedly tested 100 cancer patients and found their blood to be acidic. The details are not known, however this sounds like a small retrospective cohort observational study. It is unclear if this study has been published in a peer-reviewed journal, or replicated independently, as I could not find it. Supposedly from this he infers causation and declares that an acidic body type is the root of all evil. Really? Assuming that his findings are true (doubtful for reasons to follow), an observational study by definition shows at most correlation. It cannot prove causation.
For example, say you look at a bunch of bad golfers, and you find that they share some common traits, such as poorly fitted, beginner clubs and a towel stuck in their back pockets. You look at the pro golfers and they all have pro clubs and no towels. It would be foolish to conclude that one is a poor golfer because of cheap clubs and tastelessly hanging towels, instead of other more plausible explanations such as luck, caddie, conspiracy, and minor details such as practice/skill level and hand-eye coordination.
OK, say the 100 known cancer patients all had acidic blood, and for some unknown reason were still alive. Since they were known cancer patients, most likely they were undergoing treatment (chemotherapy, radiation, etc.). It is possible that the acidic blood is a side effect from the therapy. It is also possible that the acidic blood was caused by the cancer, and not the other way around. Perhaps the instrumentation lacked calibration, or the author’s intentions were misaligned.
Let’s turn to an article oft attributed to and allegedly written by Dr. Kuo at the Veteran’s General Hospital in Taiwan. The claims are outlandish, but since it was reported by state run TV, it is likely that he actually did write this article. The claims are not automatically true because he is a medical doctor (argument from authority); nor are they automatically false because they do not fit my worldview. Each claim deserves to be looked at carefully and critically.
First the author commits the same logical fallacy about correlation and causation. Since this is the entire premise of the article, it should be dismissed. It’s like discussing the best strategy for surviving the zombie apocalypse.
The author claims specifically:
1. Acidic blood is the root of most diseases, based on information of unknown veracity and logical fallacy;
2. Clinical manifestations of acidic blood, without citation;
3. Four causes of acidic blood, without citation or reasoning;
4. Four categories of diseases causes by acidic blood, with no citation;
5. Six causes of acidic blood despite previously listing four;
6. Blood pH can be effectively influenced by food intake, with no citation;
7. People should attempt to increase blood pH level by eating specific foods;
8. Six categories of food from highly acidic to highly alkaline, without quantification;
9. Four types of people who are at higher risk;
10. Twenty three criteria to check if your blood is acidic (!) other than a pH test.
Let’s use the standard, universal definition of acidic being pH < 7.0 and alkaline being pH > 7.0. The central claim, of course, is that acidic blood is not healthy. Regular blood pH is between 7.38-7.42. Below 7.35, acidosis occurs, above 7.45, alkalosis occurs. To have acidic blood (pH <7.0) for an extended amount of time, would mean that your whole body acid-base buffer, i.e., homeostasis, is broken. It is technically true, however meaningless, that acidic blood is not healthy, since a termination event would likely occur quickly.
The truth is, everyone already has alkaline blood.
The clinical manifestations of acidic blood that the author states: “An acidic body type manifests itself in the following ways: dull complexion; athlete’s foot; lethargy; poor cardiovascular shape; obesity” are likely moot, as a dull complexion or fungal feet seem less important, especially when you are in a coma or dead.
To break acid-base homeostasis, it turns out, is not an easy task. One would think that bad things can happen if blood pH wanders outside of this very tight range; anybody that has taken chemistry knows that it doesn’t take much to alter pH levels. Wouldn’t it logically be easier to kill someone by injecting acid instead of, say, cyanide then? Actually, someone tried that. Enter Van Slyke and Cullen, who for some sadistic reason, injected a ridiculous amount of sulfuric acid directly into the bloodstream of a poor dog. The dog not only lived, but its blood pH level did not change by much. Presumably emboldened by this experiment, many others have proceeded to test the body’s acid-base buffer with a variety of acids and alkali, not only in dogs and cats, but in humans as well. All this happened in the early to mid 1900s, presumably before the time of IRB ethics reviews. The body is really, really good at regulating blood pH levels.
It turns out, the easiest way to make your blood pH level higher, at least temporarily, is by hyperventilating. It is certainly more effective than the foods that the author claims, which are both inconsistent and have no prior plausibility. Whether you can keep hyperventilating constantly is a different story.
Out of curiosity, let’s look at some of the other claims.
Foods that are highly or moderately acidic: Egg yolk, cheese, white sugar, bread, tuna, chicken, cream, horse meat(!). I have strong doubts that these foods are in any way acidic, except for horse meat which I have not consumed, at least not knowingly. Even if you use the special pleading logical fallacy and say that these foods break down into something strongly acidic, it makes no sense because in order to do so, something strongly alkaline must be formed at the same time. It’s like pushing on the steering wheel to make the car go faster; it cancels out.
Foods that are highly or moderately alkaline: wine, grapes, egg whites, strawberry, carrots, lemons(!!!). Lemons are alkaline, so the author claims. Maybe that’s why I see all the heartburn sufferers instinctively reach for the lemon instead of the Tums at a frequency of well, exactly never. Perhaps the author really meant lemon-colored Tums; otherwise the thought that a scientifically trained medical doctor working in a top government hospital could believe that a lemon is alkaline would make me very, very depressed. And wary.
It is never made clear as to how these foods, when ingested in normal amounts can influence pH value of blood, after passing through your stomach, which is more acidic than Coke (pH 1.5~3), and then passing through your intestines, which is alkaline. Food is mostly digested and absorbed in the intestines, an alkaline environment.
How about some other claims. “Excessive intake of acidic foods result in acidic blood, which makes the blood sticky, causing poor circulation, cold hands and feet, stiff shoulder, and insomnia”. In other words, food affecting blood pH (not established with low prior plausibility) is further stretched to also increase viscosity of blood. Asserted as fact without citation or evidence, I did a quick search on the literature, and surprisingly did find a study from 2002 supporting the viscosity claim, but not the symptoms. No studies validated the premise of normal food intake having hemorheologic effects.
Let’s look at the 6 asserted reasons behind acidic blood:
1. Improper balance between acidic and alkaline foods.
2. Lack of exercise.
3. Psychological stress.
4. Acidic habits such as smoking and drinking.
5. Irregular daily routine.
6. Environmental pollution, especially water and air.
Let’s see….wine was touted as a highly alkaline food, but here it suddenly becomes acidic. I’m confused. Environmental pollution is a head scratcher, as the amount of ingested water necessary to influence homeostasis would probably be deadly on its own. And unless you’re living next to an active volcano, air affecting homeostasis is probably the least of your concern.
I am not saying that whatever the author is recommended is invalid. On the contrary, a lot of it is good, reasonable, common-sense advice on a healthy lifestyle. However, the pity is that a lot of this sound advice is given under the pretense of nonsensical, magical thinking. Sound advice should stand on its own, with evidence to back it up.
It is unnecessary to package it with misleading and factually incorrect medical conditions. An analogy can be made with say, murder. One should not murder, simply because it is morally unacceptable. Some claim that murder is unacceptable because a book from the bronze/iron age threatens that murderers will be tortured for an infinite duration, in a location with uncomfortably high temperature after death. Convoluted, and simply unnecessary.