Let’s first briefly popularize the basic theory of acid-base balance in the human body: the acidity and alkalinity of different parts of the human body (expressed as pH value, pH = 7 is neutral, less than 7 is acidic, more than 7 is alkaline) are different: for example, gastric juices are acidic, the intestines are weakly alkaline; the kidneys will regulate the acidity and alkalinity of the urine according to the metabolism in the body, so that the pH value of the blood is basically balanced between 7.35 and 7.45. 7.45, with a pH below 7.35 being acidosis and above 7.45 being alkalosis. Normal human body fluids are typically buffered solutions that maintain a strong acid-base balance with minimal pH fluctuations, and are often referred to as homeostatic. An imbalance in acid-base balance can occur only in cases of severe vomiting, diarrhea, oxygen deprivation, and serious illnesses that prevent the kidneys from excreting excess acid or alkaline material in a timely manner. On the contrary, even if you can drink a bottle of vinegar in one gulp or swallow a bottle of calcium tablets, the effect on the pH of the body fluids will only last for a few minutes at most, after which the gastric juices will still be acidic, the intestines will still be alkaline, and the pH of the body fluids will still be stable at about 7.4. After understanding the theory of acid-base balance in the human body, looking back at the so-called acid-alkaline body and food pH theory is untenable. But even in the United States, there are still a small number of experts in the promotion of this theory, a book called “TheAcid-AlkalineFoodGuide” (acid-alkaline food guide) is still in the United States of America hot sales. According to the authors, strenuous exercise leads to lactic acid buildup, certain acidic foods increase the concentration of chloride ions in the body fluids, eating large amounts of protein leads to an increase in organic acids, and in order to maintain its normal pH, the body must increase the release of calcium ions from bone, increase the efflux of potassium and magnesium ions from the cells and fluids, and increase the load on the kidneys, lungs, and skin to excrete excess acidic ions. In the long run, this can lead to osteoporosis, muscle weakness, overloading of the body’s organs, and ultimately to a variety of diseases and also to cancer. However, these explanations are not supported by scientific theories, nor can we find the results of experimental studies recognized by peer experts; as for the relationship between the “acidic body theory” and the onset of cancer, which was once put forward by a Nobel Prize winner, they have never been found in the corresponding treatises. On the contrary, judging from our common sense, the average life expectancy in developed countries is longer than that in less developed countries, and the average life expectancy of modern people is even greater than that of ancient people. Although this is mainly attributed to the great achievements in the development of medical science, if we look at the acidity and alkalinity of food alone, modern people must consume more acidic food than ancient people, because the latter could not afford to eat acidic substances due to the limitations of their economic conditions, and their diets were mainly based on starch and vegetables, and they ate very little high-protein food, and more of them should have an alkaline body. More of them should be “alkaline body”, should rarely get sick, there should be no lack of longevity, but why also “life is seventy years old”? From the point of view of modern medicine, a large number of long-term high-protein, high-sugar, high-fat diet can easily lead to obesity and increase the risk of cardiovascular and cerebrovascular diseases, but also may increase the incidence of certain tumors, but “alkaline body shall not be tumors,” this statement has no scientific basis. Moreover, strictly controlling protein intake in accordance with the guidelines of the “food acid-base theory” will, on the contrary, lead to corresponding health problems due to malnutrition. Therefore, I personally believe that there is no need for us to be scared by such alarmist theories. In our medical field, apart from acidosis and alkalosis, there are also water intoxication and oxygen intoxication. …… If it is utilized and brought into play, I am afraid that new theories and doctrines will come out tomorrow.