Nutrition and money seem to have a direct relationship: if you've got more money, you buy better food. So it's certainly harder to eat well on a limited budget, but not impossible.
Leanne Brown, author of several cookbooks, demonstrates in Good and Cheap: Eat Well on $4/Day. She visited The Exchange in 2015, and we rejoin the interview here.
The book is now out in a Spanish-language version, and in either language, it's FREE. Leanne Brown offers it in a PDF version for people who can't afford the printed version. Listen for quality tips on quality (but low-cost) eating.