One of the most popular diets, the Mediterranean diet is not only good for your gut, but also good for your heart and cognitive health. The Complete Mediterranean Cookbook: 500 Vibrant, Kitchen-Tested Recipes for Living and Eating Well Every Day ($20) has over 500 recipes from Italy, Greece, Egypt, Morocco, Turkey, and Lebanon. The diet is heavy on anti-inflammatory foods, like fish and vegetables, with fewer recipes devoted to meat and poultry. With over 3,000 5-star Amazon ratings, this cookbook definitely deserves to be added to your rotation.