Entering a well-off society, people have solved the problem of food and clothing, and all expect to improve their quality of life and live a happier, healthier and longer life. So, what is life? It has become a common concern. What is life? Some people say that life lies in exercise, which promotes metabolism and gives people vitality. Some people say that life lies in stillness. You see, the secret of the tortoise's thousand-year life lies in the word "quiet". Some people say that life lies in nutrition, eat well, drink enough, and make up in time. Why not exercise and live longer? All these statements have some truth, but they are not very reasonable. Human life is an extremely complicated phenomenon in nature. Where does life come from and where does life go? Humans have been exploring for thousands of years, and there is no accurate and complete answer so far. At present, a new discipline is emerging in the world, called cognitive science. It is a new and higher-level expansion of the study of life science, brain science, cosmology, mysticism and other comprehensive disciplines. I know a young friend who majored in this subject in a famous American university. Every time I visit relatives and friends and return to China, I bring a lot of new information about life that I have never heard of. Surprisingly, what was traditionally dismissed as "idealism", "superstition" and "absurdity" has now become the frontier subject of the latest subject research. He introduced me to a thick original English book sold in the bookstore of Shanghai International Studies University. Limited by my English level, I finally didn't have the courage to see it. It seems that although I am interested in exploring the unknown, I can't do it. Learning, researching and exploring the new subject of cognitive science can only be the business of young people. However, with my superficial understanding of China's traditional health preservation, I can also talk about what life is. I think life lies in balance. This view may be more appropriate and comprehensive than life lies in exercise, stillness and nutrition, and it is also more suitable for health preservation. Life balance is mainly three kinds of balance: nutritional balance, static balance and psychological balance. The so-called nutritional balance means that the diet is reasonable, clean and hygienic, and the nutrition is moderate. Nutrition is the material basis of life, and the calorie expenditure of daily life activities needs to be balanced by the calorie intake of some nutrients. Therefore, whether you eat and drink enough or replenish in time, you should follow the principle of balance, rationality and moderation. Now there are some proverbs about nutritional balance in the medical field and society, which are very reasonable. For example, when I was working in Beijing, I heard that "five ones a day": a glass of water after getting up, an egg for breakfast, a spoonful of vinegar at noon, a glass of wine for dinner and a bottle of milk (preferably yogurt) before going to bed. I basically did it, and the effect was good. Back in Shanghai, I heard two more words. One is "12345": a cup of yogurt every day; Two or two grains per meal; Three servings of protein a day (referring to one egg, two meats, fish and shrimp, and two bean products); Eat "four essentials" every day: not salty or sweet, coarse or fine, eat less and eat more meals, and be full in seven or eight minutes; Eat 500 grams (a catty) of fruits and vegetables every day. The other sentence is "red, yellow, green, white and black": "red" refers to tomatoes and red wine (red grapes can be used instead); "Yellow" refers to pumpkin, corn, soybean and carrot; "Green" refers to green tea and green leafy vegetables; "White" refers to oats, water bamboo and white radish; "Black" refers to black fungus, mushrooms, black beans, black rice and black sesame. In recent years, an expert who studies olive oil recommended me to eat a spoonful of olive oil on an empty stomach in the morning, which is good for my health. I have been suffering from hyperlipidemia for more than ten years. I took the exam in the first year and got results. After taking it for more than three years, I have a physical examination every year, and my blood lipid index is within the normal range. I have also recommended it to friends and colleagues, and the results have all worked. Proper nutrition is a very important issue in diet balance. Nowadays, people's overnutrition, fatty liver and obesity deserve attention. There is a proverb: "If you want to be healthy, your stomach is always empty;" I want to live a long life, and there is no shit in my intestines. "This means that if you don't have enough to eat, you must empty it. This is very important for health. A Japanese doctor specializes in human defecation and wrote a best-selling book, Intestinal Revolution, which is worth reading. The so-called dynamic and static balance means moving to keep healthy, calming to nourish the heart, exercising moderately and relaxing the nerves. For middle-aged and elderly people, the best exercise is brisk walking, and it is also good to insist on swimming if conditions permit. Japan promotes "10,000 steps a day" among its citizens. If you can't adhere to the "ten thousand steps", walking for half an hour can also achieve the effect of strengthening the heart and lungs. Besides, I play Tai Ji Chuan, do yoga, practice eighteen methods and run. Good, too. Here we should pay attention to the principle of body balance in sports. Walking, swimming, boxing, yoga, doing exercises and jogging all conform to this principle. Others, such as playing tennis and badminton, only exert their strength unilaterally, which is not conducive to physical balance and is not suitable for the elderly. Meditation with eyes closed can make people relax, clear their heads, enhance their memory, feel calm and refreshed. According to the research of Harvard Medical School, meditation can improve brain activity, metabolism, blood pressure, respiration and heart rate, lower blood pressure and effectively change cardiopulmonary function. Teacher nan huaijin's book Meditation and Immortality has very penetrating insights and experiences on how to sit still, how to meditate, what effect can be achieved, and so on. It is very practical and is a must-read book for those who care about health and longevity. In addition, the book Revolution of the Brain written by a Japanese doctor can also be read. The so-called psychological balance is to always maintain a good mood, a good mood, and be comfortable with reputation, gains and losses, life and death. This is easier said than done. Most people's sub-health is caused by psychological restlessness, and 60% of diseases are also caused by psychological and mental factors. Because, in modern society, the competition is fierce, the pressure is great, the work changes greatly, the environment is uncertain, the family affairs are complicated, and the interpersonal relationship is complex, which makes people often in a state of stress and fatigue. Psychological imbalance, fidgeting and anxiety, one after another, have become the normal state of life. It is not easy to maintain psychological balance in this environment. Eliminating various negative emotions such as worry, depression, regret, loss, sadness, anger and sadness requires self-restraint, openness, restraint and patience. This requires people to have a spiritual realm that they can afford and let go, a broad mind that does not compare with others, does not make false demands, enjoys themselves and is content with contentment, is psychologically prepared to bear setbacks, setbacks and failures, and has a good attitude of letting nature take its course, calmly coping with twists and turns. In a word, being cheerful, optimistic, open-minded, peaceful and living smartly is one of the most important secrets of health and longevity. I hope my friends will remember and never forget! This article would like to end with "The Ballad of Comfort" written by Zhao Puchu, an old gentleman and Buddhist. What is life? People may get some enlightenment from it. At sunrise, the East China Sea sets in the West Mountain, and there is also a day of sadness and joy. People are comfortable when they are not entangled in things. I like to adopt old money every month, more or less. Less meat and more vegetables, sweet in the rough, sweet in the fine. Don't choose old and new clothes, good clothes also keep out the cold, and lai also keeps out the cold. Chatting with intimate friends often, both ancient and modern. My inner grandchildren are watching, too. Children are happy and women are happy. Families comfort each other, the poor and the rich. Exercise hard in the morning and evening, be busy and optimistic, be idle and optimistic. Broad-minded, healthy, not immortal, but better than immortal.