1. Supplemental nutrition: After diet enters the human body, it nourishes viscera, supplements nutrition, qi and blood, meridians, limbs, muscles and even bones, fur and nine orifices. The nutrients needed by the human body must be continuously supplemented through diet. The nutritional effect of food on human body is also manifested in the selectivity of various foods to human organs, meridians and parts.

2. Material basis of "God": Diet is the nutritional basis of essence, qi and spirit. Only when the body is well nourished, the essence will be sufficient and the mind will be healthy.

3, treatment of diseases: dietotherapy is often better than drug treatment. There are many foods that can be used to treat diseases, such as pig bone marrow for strengthening brain and improving intelligence, hawthorn for resolving stagnation, garlic for treating dysentery, angelica mutton soup for treating postpartum blood deficiency, and adzuki bean for treating edema.

4, anti-aging: For the elderly, we must pay attention to the deployment and maintenance of diet, only in this way can we delay aging. The reason why diet is anti-aging and anti-aging is that its function is produced by tonifying kidney and benefiting qi, nourishing kidney and strengthening body. Deficiency of kidney essence can lead to signs of premature aging such as loose teeth, premature whitening and forgetfulness.