The "Neijing" (Inner Canon of the Yellow Emperor) states that one of the reasons people in ancient times "lived out their full natural lifespan and passed away at the age of a hundred" was their "moderation in diet." Moderation in diet includes regularity, eating at fixed times and in fixed amounts, and avoiding being too hungry or too full.
Dietary moderation is especially important for the elderly. The basal metabolic rate of the elderly gradually decreases with age. At the same time, after entering old age, physical activity decreases, and the energy consumed also decreases accordingly. Therefore, the energy supplied to the elderly should also be reduced accordingly.
In recent years, geriatric experts have proven that restricting dietary intake is very important for the health and longevity of the elderly. If people in old age do not reduce their food intake, leading to excess calories, it will have adverse effects on their health. Because overeating at each meal concentrates blood in the gastrointestinal tract, it is bound to cause ischemia and hypoxia in important organs such as the heart and brain, easily inducing or aggravating coronary heart disease, angina pectoris, myocardial infarction, cerebrovascular diseases, as well as diabetes, cholecystitis, etc. In addition, overeating can lead to obesity, and obesity in turn can cause many diseases. Research data shows that people who die from tumors in middle age and later are more numerous among those who overeat and are obese than among normal people. Many materials abroad also show that the weight of the vast majority of long-lived elderly people is normal or on the low side. This shows that obesity harms the body, while being light-lived leads to longevity. Therefore, many longevity researchers in the world believe that using the method of dietary moderation to slow down the speed of physiological aging is a good way to maintain health and longevity. Ancient Chinese health experts also advocated that the elderly should "eat less." The book "Laolao Hengyan" points out:
"In all matters of eating, less is always beneficial. The spleen can then grind and transport it, transforming it into essential fluids. Otherwise, even very easy-to-digest things, if eaten in excess, will instead cause harm. Therefore, it is said that eating less soothes the spleen." The book "Shoushi Baoyuan" summarizes it more clearly: "Eat only half-full and do not have too many flavors; drink wine to only a third and do not be too frequent."
According to China's dietary structure and characteristics, appropriate dietary restriction mainly involves reducing the intake of staple foods, while moderately increasing the intake of protein-rich side dishes, such as lean meat, beans and their products, dairy products, fish, vegetables, fruits, etc. This helps prevent the aging of tissues and organs and reduce the accumulation of subcutaneous fat. In addition, foods rich in fat and high-sugar foods such as pastries and candies should also be reduced, and snacks, late-night meals, and high-fat foods should be avoided. In cooking, it should be mainly light, and methods such as frying and deep-frying should be used less. In summary, appropriate dietary restriction for the elderly is beneficial for preventing disease and promoting health and longevity.