The passage of time is a continuing thing. At 18, you're going to live forever, and you are definitely not at 52, so that is a recurring topic. I still think it's the main stuff.
“A vegan diet takes care of most of what we need to do. But you'll also want to minimize the use of oils generally, because while olive oil and other vegetable oils are better for your heart than chicken fat, they are as fattening as animal fats.”