In light of current concerns regarding diet-associated dilated cardiomyopathy, it seems appropriate to expand upon what constitutes a “good” diet and how you, the pet owner, can determine on your own what is the best diet to feed your pet. 
The pet food industry is a multi-billion dollar industry and significant amounts of money have been spent on training pet owners to look at ingredient. We’ve all seen those Blue Buffalo commercials! The problem is that the ingredient list is perhaps the least useful item to use when it comes to evaluating a pet food formula. I realize that may sound shocking, but stick with me and I’ll explain why. 
Many pet owners are surprised to learn that pet food ingredients must be listed in order of weight. This includes water weight, so ingredients with high water weight are going to be listed before dry ingredients. In other words, a diet with deboned chicken (70% water) as the first ingredient may actually contain less chicken than a diet with chicken meal (<10% moisture) as the second, or even third, ingredient. Another popular trick for manipulating the ingredient list is to utilize ingredient splitting. Ingredient splitting is where the manufacturer takes a single, whole ingredient and lists it according to its separate parts (such as pea protein, pea fiber, and pea starch instead of simply listing “peas”). This allows the manufacturer to list the separate components further down the ingredients, making it appear as though there is less of that particular ingredient present in the formula. In all honestly, the only thing the ingredient list is good for is to look for ingredients that need to be avoided in the event of a food allergy or food sensitivity. It tells us absolutely nothing about the quality, quantity, or sourcing of any of the ingredients. 
So what should we be using to evaluate the quality of a particular diet? If ingredient lists are unreliable and precise formulations closely guarded proprietary secrets, the only criteria we can successfully measure is the level of knowledge and expertise of the manufacturer. Specifically that boils down to the following:

  1. At least one full-time, board certified veterinary nutritionist or PhD nutritionist should on staff and responsible for diet formulation. In addition, the company should employ a team of food scientists, chemists and nutritionists to properly address all the intricacies of formulation that are necessary to properly and thoughtfully craft a diet.
  2. Diets should be produced in manufacture-owned and operated facilities, rather than farmed out to third parties.
  3. Strict quality control measures should be in place that evaluate the integrity, composition, and safety of the diet, starting from the supplier and ending well after production has finished.
  4. Formulas should be found to be complete and balanced for a given life-stage by completing AAFCO approved feeding trials, rather than by formulation to meet AAFCO requirements.
  5. A complete guaranteed analysis should be available upon request in order to ascertain the exact amount of a specific nutrient in a predetermined sample size (for example, the grams of protein per 100 kilocalories).
  6. The calories per serving should be readily available.
  7. The manufacturer should be conducting and publishing research in peer-reviewed journals.
These guidelines are all reasonably objective and straight forward to measure and ascertain. They help to ensure that an extensive level of knowledge and expertise is present when formulating food for our pets and that the various formulations are driven by science and research, rather than marking trends. When it comes to quality pet foods, experience is the name of the game and science reigns supreme.