- Eat, Drink, and Be Healthy : The Harvard Medical School Guide to Healthful Eating (2001)
- Nutritional Epidemiology, 3rd edition (2013) (co-edited with Meir Stampfer)
- Willett's Nutritional Epidemiology, second edition (2018) (edited by Willett)
- The Salt Sugar Fat Fix : How the Food Giants Hooked Us (2020) (co-authored with Marion Nestle)
In addition to these books, Walter Willett has published scientific articles, reviews, and policy recommendations in various medical and nutritional journals.