Nutrients promote growth, provide energy, and help the body perform metabolic functions, such as maintaining and synthesizing tissues and regulating temperature. Dogs are omnivorous, meaning they can obtain these nutrients from a variety of foods: meats, grains, fruits, and vegetables. Providing high-quality nutrients in the correct amounts is the best way to ensure that your pug leads a long and healthy life.

Dogs need protein, carbohydrates, fats, and water to maintain good health. Meat, eggs, fish, grain, or a combination of meat and grain all provide protein. Common meat proteins you might see listed on a dog-food label include beef, chicken meal, and meat by-products. Protein that comes from animals is of higher quality than protein from grain.

The Label Breakdown

Besides providing the most concentrated form of energy of all the nutrients, fat has the benefit of being highly digestible. The downside is that foods high in fat taste so good that dogs — especially pugs — tend to eat too much of them. That's one of the reasons you need to exercise portion control, because your pug won't do it for himself. The main sources of carbohydrates in dog foods are grains such as corn, oats, rice, and wheat. They provide the body with complex carbs in the form of starch and are cooked to enhance digestibility and flavor. Fiber comes from sources such as beet pulp and rice or wheat bran. As with most things, moderation is key when it comes to fiber in the diet. Too much leads to puggy flatulence, which you definitely want to minimize.

Water is the most important nutrient in a dog's diet. It makes up 60 to 70 percent of a dog's body and is important for cell and organ function. Dogs can go for long periods without food — although this would make for a very unhappy pug — but without water they can die within days.

Making sure your pug gets plenty of water, in addition to the right food, is essential for maintaining good health.

Vitamins and Minerals

Vitamins are organic molecules that serve an essential function in many of the body's metabolic processes. With a few exceptions (such as vitamin C), most vitamins can't be synthesized by the body, so they must be provided in the diet. Vitamins are powerful, so the body requires only a tiny amount of each one. Vitamins fall into two categories: fat-soluble and water-soluble. Fat-soluble vitamins — A, D, E, and K — can be stored in the liver, while water-soluble vitamins are excreted in the urine if the body doesn't use them right away. Among the vitamins you might see on a dog-food label are thiamin, riboflavin, niacin, pyridoxine, pantothenic acid, biotin, folic acid, and choline.

Like vitamins, minerals are essential for life, although the body needs only tiny amounts to function. Minerals provide skeletal support and are involved in nerve transmission and muscle contractions. Macrominerals, which include calcium, phosphorus, and magnesium, account for most of the body's mineral content. Microminerals, also called trace elements, are present in the body in very small amounts. Microminerals include zinc, manganese, iodine, and selenium.