GoodGuide studied 1,500 products in 50 brands of dog and cat food to rate the top products in dry and wet petfood, and Science Diet took the number one spot for both dog and cat food brand.

Ratings take into account things like concern for the environment, personal health and social responsibility to come up with scores in the categories of health, environment and society. The top-five rated brands, according to Good Guide, are:

Top 5 Cat Food Brands 

1. Science Diet
2. Eukanuba
3. Evo
4. Innova
5. Eagle Pack

Top 5 Dog Food Brands 

1. Science Diet
2. California Natural
3. Innova
4. Evo
5. Karma

In addition, GoodGuide provides consumer tips on buying the right petfood. Pet owners should look for products that show transparency by revealing such information as calories to better monitor pets' health. They should also choose foods that have undergone real-life tests, not just lab tests, which will be represented by a phrase like "Animal feeding tests using AFFCO procedures substantiate that (name of product) provides complete and balanced nutrition." Finally, consumers should pay close attention to marketing claims and verify them through other sources if possible.