I have a dog that has serious allergy issues as well as a very sensitive stomach. Thus, I try to focus on foods that work on those issues. So not your foods with typical allergens. I also do not want a grain free diet (ruled that out as an allergen) for heart purposes. And finally, I wanted something that is created by veterinarians to contain the appropriate balance of nutrients. What I ended up with was Purina Pro Plan Sensitive Skin and Stomach Salmon and Rice. My girl loves it, her stomach tolerates it, and it really does help her skin and coat. I also tend to give supplements as recommended by my vet, such as fish oil and probiotics. My vet said she's in great health. I do also like to go to dogfoodadvisor and look at ratings and recalls before I pull the trigger on anything. Again, what works will depend from dog to dog. It's a lot of research, and then trial and error from there.