60-year-old male (female) is 40kg thin, 1.6m, and doesn't eat much meat and greasy things. How can you make her fat? !
It is normal for people to like to eat some light food when they reach a certain age. If you are worried, buy some nutritious food and cook it lightly, just like fish porridge oil. Don't put too much nutrition to keep up! Moreover, people are old, their physical conditions are not as good as before, and their absorption is not as good as before. No matter how much you eat, you can't get fat!