A good place for basic dog food quality evaluation is the Dog Food Advisor database. They give star ratings and everything to make comparisons a bit easier. In general, lower carbohydrates and less fillers (corn, food coloring, by-products) can lead to improved behavior. Most of the major brand food sold at grocery stores are not ideal — they are the canine version of fast food. Dogs may scarf them down, but they tend to lead to less focused attention and more hyper behavior.
Is it bad to give my dog people food?
It’s great to give dogs high quality (and plain) people food. Meat, vegetables, a small piece of cheese, yogurt, and peanut butter can all have a place in either training or the dog’s diet. A bunch of pizza crusts aren’t ideal. Any cooked bones are dangerous, as they can splinter, so don’t toss the dog that plate of gnawed chicken wings. Normal meals should be adjusted down accordingly, just as with training treats.
The high rated foods seem really expensive.
Keep in mind that the better foods usually have fewer non-digestible fillers, and thus you can feed much less. This is why dogs fed high quality foods have much smaller poops. So less scooping is another nice benefit.
What about feeding raw?
It can be more work for the person, but nutritionally it is sound as long as it’s done right.
For those who want a deep dive: