Animal and plant-based proteins
The sources of protein are divided into animal and plant sources. The protein contained in meat is animal protein, but many meats are oxidized as soon as they are fried and fried, and the protein is denatured and becomes inferior protein.
The meat that contains the best protein is fish, followed by white meat and then red meat. The difference between white meat and red meat is the proportion of fat. Therefore, chicken breast is said to be white meat, while chicken leg meat is red in color, has more blood cells, and has higher fat, so it is red meat. Some people say that white meat is healthier, and this is the truth.
As for plant-based protein, beans have the highest content. For example, dry soybeans have a protein content of 40%, and the other 20% is fat, 35% carbohydrates and 5% minerals. A popular food in Middle Eastern countries is called lentil, which some people translate into Chinese as lentils. They are flat and round, like a flying saucer, and come in green, red, yellow, and black varieties. When people in the Middle East cross the desert, they rely on a camel, a pack of lentil and a jug of water. It can be seen that lentil is a nutritionally balanced food. In addition to vitamins and minerals, it is also rich in fiber, protein and starch. The proportion of protein is about 25%, fat 0.7%, and carbohydrate 60%. In the United States, lentil is less likely to cause allergies than soybeans. There are relatively few people eating in China, but those who are interested may wish to try it. The cooking method is usually to add water and cook it into a thick bean soup, which feels a bit like broth and tastes good.
The proportion of amino acids in each protein food is different, and the most complete proportions are eggs, duck eggs and meat, so animal protein is also called "complete protein". Plant-based proteins may have incomplete proportions, so they are called "incomplete proteins." For example, cereals (including brown rice and whole wheat), nuts and seeds lack lysine, while vegetables and beans lack methionine. Therefore, I usually recommend that vegetarians eat cereals and beans together, and the amino acid ratio It will form a complement, making protein absorption more complete.
The closer to human protein, the better
According to the definition of nutrition, the quality of protein depends on each ingredient in it.Whether the ratio of required amino acids is close to that of humans, the closer the better. Another criterion is how well the protein you eat is absorbed by your body? Usually 70% can be absorbed, which is already a good protein. The protein in which the amino acid ratio is closest to that of humans is eggs. The protein in meat is also good, and the ratio is very close to that of humans.
Some people are worried about cholesterol and dare not eat more eggs. In fact, eggs are a very healthy food. The key depends on how you cook them (see Chapter 4 "Myth 2: Eat less high-cholesterol foods?" for details). However, due to mass production and the addition of a lot of growth hormones, estrogen and antibiotics to the feed, the quality of modern eggs is much worse than before. When cheap eggs are opened, the egg whites disperse like water; in better eggs, the egg whites are semi-solid. The nutritional content of eggs is related to the chicken feed. Some chicken farmers are more health-conscious and feed their chickens cereals or grasses containing omega 3. The eggs they lay contain a large amount of omega 3 and are more nutritious. Therefore, it is worthwhile to buy better eggs, which are not only more nutritious but also do not contain artificial hormones.
So, how many eggs should you eat a day? In fact, as long as people are not allergic to eggs, in principle, it is okay to eat 1 to 3 eggs a day. For some people who particularly need to supplement protein, it is okay to eat four or five eggs a day. But here it refers to boiled eggs, braised eggs and tea eggs. If it is scrambled eggs and fried eggs, because cholesterol is easily oxidized and protein is easily denatured, it is better not to exceed 1 a day.
Balanced protein intake
Although protein is an essential and important nutrient in meals, it cannot be consumed endlessly. When it is deficient, it can cause blood sugar instability, hypothyroidism, and adrenal fatigue. For example, when tryptophan is deficient, it can lead to depression, sleep problems, and excessive sensitivity to pain. However, eating too much can also lead to the loss of electrolytes and minerals, resulting in arrhythmia or osteoporosis, and will increase the burden on the liver and kidneys. Therefore, kidney dialysis patients must be very careful about protein intake.
Eating too much protein often means eating too much meat. High-temperature barbecues can easily oxidize animal fats and cholesterol, leading to an increase in bad cholesterol (LDL), leading to heart disease or stroke. In addition, a high-protein diet can easily produce high purine levels, which can cause gout. In addition, protein metabolism requires a lot of vitamin B6 and B vitamins, so eating too much protein can easily lead to vitamin B6 deficiency. B vitamins are found in many vegetables, so when eating a lot of meat, remember to also eat a lot of vegetables to maintain normal protein metabolism.
Eating too much protein can also cause high acidity in the body. The normal pH in the body should be maintained between pH7.35~7.45.It can be too acidic and not too alkaline. Too acidic will cause many chronic diseases. The most common one is the loss of calcium, magnesium, zinc and other minerals, because in order to neutralize excessive acidic substances, the body must release some alkaline minerals. The most commonly used substances are calcium and magnesium from bones. This is the main reason why people who are addicted to meat are prone to osteoporosis. Milk is also an acidic food, so I don’t agree with the idea of using milk to supplement calcium, because the more milk you drink, the more acidic your body becomes, which makes it easier for you to lose calcium and suffer from osteoporosis, unless you also supplement a large amount of alkaline foods (such as vegetables) to balance your body's pH.
The importance of protein to the body
In recent years, a variety of weight loss methods have become popular. For example, the "Atkins Diet", which claims to eat only meat and no meals, advocates taking in a large amount of protein and as few carbohydrates as possible; on the contrary, there are also diets that advocate eating a large amount of protein. The "Dean Ornish" and "Pritikin Diet" are high in carbohydrates, but eat a small amount of fat and moderate amounts of protein; the more moderate ones include the "Zone Diet", which introduces Between the Ajin diet and the Ounixu diet, it is emphasized that the ratio of carbohydrates, protein and fat should be 40:30:30. In addition, there are blood type diet, detox diet, vegan diet, lacto-ovo-vegetarian diet, hypoallergenic diet, low-fat diet, fasting diet, low-salt diet, gout diet, raw food diet, longevity diet, Indian diet, Chinese diet, Ryukyu diet diet, the Japanese diet, the Mexican diet, the Mediterranean diet, and the Pyramid Diet published by the USDA many years ago. Such a wide variety of various dietary methods are very popular, and they have theoretical propositions behind them, and some people follow them.
So, why do we need to talk about these first when talking about the importance of protein? Because the proportions of protein intake in these different diets vary greatly. Some eat almost no protein at all, and some only eat protein at all. So should you eat protein? How to eat protein? It has caused confusion among many people. In fact, no one diet is suitable for everyone, because everyone has different physiques, different growth backgrounds, different living environments, and different levels of physical health. Therefore, which diet is best for you depends on your proficiency in Chinese and Western medicine and Medical experts in various types of diets will test and analyze your diet and tailor a comprehensive diet plan for you. In this book, I will also explain in detail the misunderstandings, pros and cons of various diets that I know. I believe that after reading this book, you will definitely know what you should eat. What not to eat? What can be eaten? What should you eat less of? What can’t be eaten at all? Have a basic understanding. If you have further needs, I would like professional assistance. I hope there will be more and more help.The more doctors and nutritionists receive training in this area, the more they can serve the many people in urgent need.