Book excerpt: Nutrition aside, there are other interesting topics worth exploring in the pursuit of health. Can cancer be prevented? Why doesn’t everyone live long, healthy lives? What is the relationship between cardiovascular disease and the immune system? How does the immune system affect overall health? Which is a healthier food option: natural and wholesome plant foods or animal-based foods? How do our lifestyles affect our health? Good health is not a secret. To achieve good health, we must first understand it. By drawing links between diet, health, and the immune system, this book provides fascinating insights into the preventive science of Nutritional Immunology.