Because one is bacterial and the other is fungal, they respond to different ingredients
I find this book to be the best starting point for people on how to learn more about the physiology of dieting, how to implement dieting principles based on science which works time and time again, avoiding the most common errors, implementing free meals and refeeds to make the diet even more effective (nothing is called cheating or breaking the diet here), and how to move back to maintaining your weight in a simple and easy way even without counting calories
For example, if you burn 600 calories through a hard cardio workout, energy compensation may subtly influence you to burn fewer calories the rest of the day, in general, around-the-house activity
To combat this, experts recommend eating smaller, more frequent meals, avoiding greasy or spicy foods, and incorporating bland foods like crackers, toast, or applesauce into your diet until the nausea subsides
The important thing is the importance of food sources in supporting rather than supplementing nutrition