When most people eat, they may not consider the food they put into their bodies is not only fuel for energy, its nutritional value helps ward off chronic systemic diseases like cardiovascular disease and diabetes, prevents deficiencies and curbs issues like obesity and weight gain and metabolic syndrome. There are seven major classes of nutrients we must consume or face serious illness and even death. They are vitamins, minerals, carbohydrates, proteins, fats, water and fiber. Let's break down the nutritional information available.

The nutritional value of a product is placed on food labels so that you can evaluate the nutrient content in a single serving of a food item. Nutritional information is provided in a format regulated by law and uses established daily values for comparison. This breakdown allows you to compare foods consistently from product to product and gives you a break down of the nutrients it contains and the energy provided by the food.

Fats

Fats are composed of fatty acids bonded to a glycerol. Fat is classified as either saturated or unsaturated. Generally, saturated fat is solid at room temperature while unsaturated fat is a liquid. Unsaturated fats may be further classified as mono-unsaturated or poly-unsaturated. Trans fats are saturated fats which are typically created from unsaturated fat by adding the extra hydrogen atoms in a process called hydrogenation.

Fiber

Dietary fiber consists mainly of cellulose that is indigestible because we do not have enzymes to digest it. Fruits and vegetables are high in dietary fiber. Dietary fiber is important because it provides bulk to the intestinal contents and stimulates peristalsis - the rhythmic muscular contractions passing along the digestive tract.

Water

About 70% of the non-fat mass of the human body is made of water. Normally, about 20 percent of water intake comes from food, while the rest comes from drinking water and beverages. Water is excreted from the body in many forms; through urine and feces, through sweating, and by exhalation of water vapor in the breath.

Minerals

Dietary minerals are the chemical elements required by living organisms, and are present in common organic molecules. They include macro-minerals like calcium, magnesium, and sodium, as well as trace minerals such as cobalt, copper, chromium, iodine, iron, manganese, nickel and zinc. Nutritional supplements are available to

Carbohydrates

Complex carbohydrates take longer to metabolize since their sugar units are processed one-by-one off the ends of the chains. Simple carbohydrates are processed quickly and thus raise blood sugar levels more quickly resulting in rapid increases in blood insulin levels compared to complex carbohydrates.

Protein

Protein is composed of amino acids that are our body's structural materials like muscles, skin and hair. The body requires amino acids to produce new body protein and to replace damaged proteins that are lost in the urine. Amino acid requirements are classified in terms of essential and non-essential amino acids. Consuming a diet that contains adequate amounts of essential amino acids is particularly important for growing animals.

Vitamins

As of 2005, twelve vitamins and about the same number of minerals are recognized as "essential nutrients", meaning that they must be consumed and absorbed in nutritional supplement form - or, in the case of vitamin D, alternatively synthesized via UVB radiation - to prevent deficiency symptoms and death.

In the US, nutritional information standards and recommendations are currently controlled by the US Department of Agriculture. Dietary and exercise guidelines from the USDA are presented as the food pyramid, which supersedes the four food groups.