The balance between acidic food and alkaline food can be divided into acidic food and alkaline food according to the main mineral elements. Generally speaking, meat, poultry, fish, shellfish, shrimp, eggs, peanuts and other non-metallic elements in our daily staple food rice, white flour and non-staple food contain more phosphorus, sulfur and chlorine, which are metabolized into acidic substances in the human body, making body fluids weakly acidic. Therefore, these foods are physiologically called acidic foods. Most fruits, vegetables, beans, tea and milk contain many metal elements such as sodium, potassium, calcium and magnesium, which are metabolized into alkaline substances in the human body, making body fluids weakly alkaline. Physiologically, these foods are called alkaline foods. The body can only absorb alkaline substances directly from food; Acid-forming substances can come from food or be provided in the form of intermediate products and "end products" of food metabolism in the body.
It should be pointed out that the taste of food is not sour, but acidic. Sour substances in food are organic acids, such as citric acid and its potassium salt in fruits, which can be completely oxidized in the body. Citric acid can eventually produce carbon dioxide and water, leaving alkaline elements in the body. Therefore, this kind of food with sour taste is physiological alkaline food.
Under normal circumstances, human blood is weakly alkaline, which is beneficial to physiological activities. Because the human body has an automatic buffer system, it can handle the acid-base relationship by itself, which can keep the acid-base value in the blood within the normal range and achieve physiological balance. However, the buffering capacity of the organism itself is limited. If in daily life, all kinds of foods are often mismatched and taboos are ignored, it will easily lead to the imbalance of acid-base balance in human physiology, and in most cases, it will easily lead to the high level of acidic foods.
People in China have developed a diet with acidic food rice and flour as the staple food, and urine is usually acidic. If we don't pay attention to properly control the intake of acidic foods such as animal protein and less alkaline foods such as vegetables and fruits in daily life, it will easily lead to acidic substances in the blood, which will not only increase the consumption of alkaline mineral elements, but also lead to calcium deficiency in the human body, blood color deepening and viscosity increasing, causing acidosis. Therefore, we must pay attention to the proper combination of acidic food and alkaline food in diet to maintain physiological acid-base balance and prevent acidosis. At the same time, it is beneficial to make full use of various nutrients in food and achieve the effect of improving the nutritional value of food. In order to keep the balance between acidic food and alkaline food, it is necessary to mix them properly according to their pH values.
The proportion of eight essential amino acids in protein in diet is in balance with human needs. In the process of digestion, protein is completely decomposed into amino acids under the action of various protein hydrolases, and then absorbed in the form of amino acids, which are utilized by the body to form various protein. Protein contains more than 20 kinds of amino acids, which can be divided into essential amino acids and non-essential amino acids. The so-called essential amino acids are necessary for human body, but they cannot be synthesized in the body and must be provided by food. The so-called nonessential amino acids are essential for human body and can be synthesized by themselves without food supply.
Generally speaking, most animal proteins contain 8 kinds of essential amino acids with high content, which is close to the requirement of human body, so they are called high-quality protein. The low lysine content and poor quality of plant proteins have affected the utilization rate of protein. However, soybean protein contains high lysine, which is also a high-quality protein. Nevertheless, no matter what kind of food protein's amino acid composition, it can't fully meet the needs of the human body. Only when several kinds of foods are mixed together, the amino acid composition of protein in all kinds of foods is close to the needs of human body, and it reaches the best proportion in protein.
Therefore, in order to balance the contents of eight essential amino acids in protein and make the proportion meet the needs of human body, attention should be paid to the collocation of animal protein, usually plant protein and soybean protein in the diet composition, so as to ensure that high-quality protein accounts for 1/3 of the total supply in protein.
The three thermogenic nutrients in the diet should be balanced in a certain proportion. Protein, fat and sugar in diet not only provide necessary energy for human body, but also have its unique physiological functions. They use, restrict and transform each other and are in a dynamic balance. The three thermogenic nutrients must be kept in a certain proportion, so as to ensure a balanced diet and achieve the purposes of health care, health preservation and disease prevention.
According to the recommended dietary allowance standard for Chinese residents, the intake ratio of sugar, protein and fat should be (6 ~ 7):1:(0.7 ~ 0.8) if calculated by weight; According to their respective percentages of total heat energy, sugar accounts for 60%-70%, protein accounts for 10%- 15% and fat accounts for 20%-25%. Once the normal ratio of protein, fat and sugar is broken, it will cause a series of metabolic disorders. For example, the lack of heat energy and protein in diet will lead to malnutrition, anemia and multiple nutrient deficiencies, which will have a serious impact on human health; Excessive heat and protein in diet not only waste valuable food resources, but also cause obesity, diabetes and cardiovascular diseases due to excessive intake of heat and fat, which is also harmful to human health.
In a balanced diet, the mechanism of maintaining the proportion of three thermogenic nutrients is mainly determined by their metabolic characteristics in the human body. The metabolic characteristics of sugar in human body are: it can be quickly absorbed by the body, and the oxygen consumption is low. The final products of metabolism are carbon dioxide and water, which does not increase the burden of metabolism. The metabolic characteristics of protein and fat are: complex metabolic process and high oxygen consumption, and the final products of their metabolism are acidic substances such as ammonia, nitrogen and ketone bodies. If protein and fatty foods are eaten too much, they will eventually turn into fat in the body, leading to excessive calorie intake. If the activity is low, the excess part will be converted into fat deposited in the body, forming obesity. If it is not controlled, it will produce a series of changes in physiological functions and even lead to diseases. On the contrary, if you don't eat fat to lose weight, you can't eat more staple food (mainly sugar). Although the intake of protein and fat is limited, excessive intake of sugary foods will also be converted into fat in the body, and excessive storage of fat will also lead to diseases.
Maintaining a certain proportion of the three thermogenic nutrients can also protect protein from sugar and fat. If people don't eat enough sugar and fat, and the heat energy supply in the body is not enough, they will decompose the protein in the body and release heat energy to supplement the shortage of sugar and fat. But protein is the "building material" that constitutes the human body. Without it, it will seriously affect health. If we ingest enough sugar and fat at the same time as protein, we can reduce the decomposition of protein and use it to repair and build new cells and tissues.
In a word, human health depends on reasonable nutrition to a great extent. The fundamental thing to ensure reasonable nutrition is a balanced diet, and the principle of taboo should be followed. Otherwise, it will cause diseases, which is not good for your health.