If lucky enough to miss cancers and heart disease in one's 40s and 50s, low-calorie (low-volume) dietary habits might delay the effects of aging: Calorie Restriction and Aging, Eating less--while maintaining adequate nutrition--is a recipe for longer life in many animals.
If you don't care, good for you. If maintaining energy, vitality, and functionality matters to you, then it's worth thinking about.
While we recommend low-carb or even keto diets for weight loss programs (and even say skip the exercising - it doesn't help with that goal very much), the simplest and easiest body fat fitness plan is volume control.
That means volume of beer, soda pop, meals, and snacks. We've all noticed how avidly overweight people eat with no awareness of satiety - only of "fullness" (or of when all the food is gone). Portion control takes a little thought and planning.
My experience is that restaurants in the US and Europe (except for the fanciest ones) tend to serve the equivalent of two or three meals for a fit healthy person. However, there is no law that we must clean our plates. The Great Depression is long gone.
I've posted in the past, literally ad nauseum, about "false hunger," and ritual or recreational eating.
For devoted weight trainers, heavy-lifters, it is more complicated for any age.
