I've since discovered another piece of advice I wish she had taught me. It's one I'll pass onto my daughter.
The best time to go shopping for groceries is right after a grueling work out. I always feel great after working out and the last thing I want to do is ruin that work out with bad food. I stock up on fruits, veggies and lean meats. I buy good foundation foods like brown rice and whole grain bread. I avoid the sweets and sugars. I don't dare put junk food in my cart. A bag of chips or a tray of brownies has no power over me. It's a great feeling!
While some might be tempted to splurge after a work out I feel the opposite. I feel healthy and I want to continue it with good, fresh, whole foods. And it makes it easier to stick to my budget because I'm buying things on my list and controlling the impulse buys. Score!