All mammals need a mix of vitamins, minerals and fatty acids that can’t be produced by the body and must be supplemented by the animal’s diet, but each species’ dietary needs are unique. And cats are no exception.
Unlike dogs and humans, cats are carnivores. They evolved eating different foods and thus, need different essential nutrients. For example, cats can’t synthesize adequate amounts of the amino acid taurine. If it’s not supplemented by their diets they can develop eye and heart problems. 
A happy cat holds her tail high and steady.