Calories
To maintain a healthy body weight, pets needs to consume enough calories. In animal nutrition, a Calorie, the unit that we see on the Nutrition Facts label for human foods, is typically called a kilocalorie, or just “kcal”.
Protein
Protein is made up of building blocks called amino acids. Dogs and cats need a certain amount of protein every day, but they also need adequate amounts of each amino acid in the correct proportions to each other to use them most efficiently.
Fat
Fat, like protein, is made up of smaller units called fatty acids and while all animals need some fat in their diet for good health, certain fatty acids are critical to good health and body function.
Carbohydrates
While adult dogs and cats do not have a strict requirement for carbohydrates in the diet, moderate levels of carbohydrates are well-tolerated by both species. Adding carbohydrates to the diet allows for lower fat, lower calorie diets.
A diet of just protein, fat, and carbohydrates will not provide everything an animal needs for good health, however. While vitamins and minerals do not provide any calories, they are of critical importance for normal body function.
Minerals are the main components of bone and are also critical for normal muscle contraction, including the heart. They are also critically important as components of the red blood cells.
Vitamins are critically important for normal body functioning – they help the cellular machinery to work to breakdown protein, fat, and carbohydrates.
Water provides no calories and only small amounts of minerals, but it must be consumed in appropriate amounts every day for normal body function.