Marion Nestle’s book What to Eat is a fascinating book. She explores the supermarket through multiple lenses, providing clarity to the unbelievably perplexing issues that face us multiple times a day as we decide what to put in our mouths.
She covers the nutritional issues. She unravels the links between healthy food and the environment. She exposes the marketing pushes that encourage us to make choices against our best interests. Best of all, she does all this while writing intelligent, clear, non-condescending, and entertaining prose.
I read the whole book, but I think it would also serve as a useful reference if you felt the sudden need to evaluate your choices around fish, for example. I can always use more motivation to eat better and facts are useful, so I will keep it on my shelf.