Rumor debunked by experts
"If you can balance your body's pH level and turn your body into a weakly alkaline state, no matter what type of cancer you have, it will change and be cured."
"Cancer cannot form in a weakly alkaline human body; cancer can only form in an acidic body."
"People should eat more alkaline foods to make their bodies alkaline."
This theory, which classifies human constitutions into either acidic or alkaline and advocates for eating more alkaline foods to change the body's constitution, has been around for a long time. Recently, Luo Jing's death from lymphoma has been used as a pretext to claim that cancer is also caused by the body becoming acidic. Is this theory scientific?
Where does this theory come from? Tracing its source, the classification of acidic and alkaline constitutions seems to originate from vegetarian theory: most vegetables are broken down by the body into alkaline substances, while proteins from meat and eggs produce acidic substances. Therefore, eating more alkaline foods makes the body more alkaline and healthier.
About "Food Changing Body Acidity and Alkalinity"
Food cannot change the body's pH level
Experts say: It is almost impossible for food alone to change the pH of body fluids. From a nutritional perspective, the so-called human body acidity and alkalinity is an academic joke.
Nutrition classifies foods into acidic, alkaline, and neutral, but the acidity or alkalinity of food cannot change the body's pH. If this pH refers to the blood's pH, the normal range for human blood is 7.35 to 7.45, and the body itself has a very strong self-regulation ability.
For example, alkaline foods like fruits and vegetables have higher levels of potassium and calcium, but the human body doesn't absorb everything it's given. What it can't absorb is excreted through urine and feces. This precise bodily function is what prevents an excess of any single component from causing disease.
Whether eating acidic or alkaline foods, if a person consumes only one type and occasionally overdoes it, the body can self-regulate and repair. However, if this is done long-term, the body won't be able to repair itself in time, leading to disease. And once a disease has formed, the blood's pH level will indeed change.
But the reverse cannot be inferred—that "an acidic constitution causes disease." There is no experimental data in clinical practice to prove this.
About How pH is Measured?
It refers to blood
The analysis above concerns the pH level of the body's blood. So, does this so-called body pH refer to other body fluids?
Acidity and alkalinity refer to the blood. The water inside and outside of cells cannot be measured, and medicine does not use this as an indicator for judging disease.
Body fluids excreted from the body, such as urine, do have issues of acidity and alkalinity. "Urine acidity" and "body fluid acidity" are two different concepts. For example, taking baking soda tablets can alkalize urine. Eating too much seafood can cause some people's uric acid levels to become too high. This恰恰 shows that nutrients the human body cannot absorb are excreted through waste fluid—urine.
About "An Acidic Constitution Leading to Cancer"
Both excessive acidity and alkalinity can cause disease
Regarding the view that "eating more alkaline foods prevents cancer," this theory has some truth but is not entirely scientific and does not represent the situation of all patients. Alkaline foods are mostly vegetables and fruits. According to this view, if one is a long-term vegetarian, they won't get cancer? Obviously, that's not the case.
There is a saying in oncology: the poor get stomach cancer, the rich get colon cancer. This means that in the past, poor families who ate high-fiber foods (vegetables are high in fiber) for a long time suffered from stomach wear and tear, leading to disease. The rich, who ate large amounts of meat and fish for a long time, couldn't handle the burden on their intestines, which deteriorated into colon cancer. This is just a simple analogy; in reality, the causes of cancer are varied and cannot be determined by what you eat or don't eat.
Therefore, whether it's acidic or alkaline foods, advocating for eating only one type is incorrect and can easily lead to disease, including cancer. Zhang Haibo analyzes that this view has some significance in today's society because people generally consume too much high-fat food and neglect eating vegetables and fruits.
However, for dietary principles, nutrition experts all recommend following the "Dietary Balance Pyramid," reducing meat, eggs, and dairy products, and increasing vegetables, fruits, and whole grains. One must have a mix of meat and vegetables, a balance of acidity and alkalinity, and a balanced diet. Eating only alkaline foods (fruits and vegetables) or only acidic foods (meat and eggs) long-term will overwhelm the body's self-regulation system, inevitably leading to various diseases.
Conclusion
A balanced diet is the key to fighting disease
From the analysis above, it is clear that the acidity or alkalinity of food does not affect the pH of human blood. The human body has a normal pH range for blood; being too acidic or too alkaline is not good and indicates that the person already has a disease.
As for what to eat, there is no need to focus solely on alkaline foods. One should still follow the Dietary Balance Pyramid, with a mix of meat and vegetables and a balance of acidity and alkalinity, to ensure a balanced diet. At the same time, one must also exercise more. When the body's nutritional needs are met, its resistance will also increase, which is the real way to ward off all kinds of diseases.
Acidic and Alkaline Foods in Nutrition
Acidic Foods
Foods rich in minerals such as sulfur, phosphorus, and chlorine, whose final metabolic products in the body are acidic.
Includes: protein-rich meats, fish, poultry, eggs, as well as grains and nuts like peanuts, hazelnuts, and walnuts.
Alkaline Foods
Foods rich in minerals such as potassium, sodium, calcium, and magnesium, whose final metabolic products in the body are alkaline.
Includes: tofu, milk, celery, potatoes, bamboo shoots, mushrooms, carrots, kelp, mung beans, bananas, watermelon, strawberries, and most vegetables and fruits.