1, "Old people should eat less and eat more when they live longer" is correct. The function of various organs in the elderly is declining, and eating less and more meals is convenient for digestion and absorption. But according to you, your grandfather just eats less now, not more meals. It is suggested not to correct your grandfather's idea of eating less now, but to provide him with more meals of food, such as fruits, nuts, milk and so on.

2. Proper exercise is necessary. Exercise can accelerate the blood circulation of the body and deliver nutrients to all parts of the body to meet the needs of metabolic renewal of various organs of the body. At the same time, the garbage in the body is discharged from the body to achieve health and longevity.

3, exercise can increase the digestion of calories, so the appetite will be greater, and now your grandfather has less exercise, which will also lead to a decline in appetite. I suggest that you or your family often take him out to play. Older people are afraid of loneliness, sometimes they don't want to go out alone, or they are afraid of being injured again, which will affect themselves and their families. If you have relatives around you to accompany him, go out for a walk, chat, take a walk, or listen to his stories and play chess with other old people, you will make him feel warm and appreciate your care and love for him.