Anorexia: Loss of appetite leading to severe weight loss.

Antioxidants: Natural or synthetic vitamins A, C, E, selenium, and some enzymes that absorb and attach to free radicals, preventing them from attacking normal cells.

Calories: A measurement of the energy your body gets from food. Your body needs calories to "fuel" all of its functions, such as breathing, blood circulation, and physical activity. When you are sick, your body may need extra calories to fight fever or other problems.

Carbohydrates: One of the 3 nutrients that supply calories to the body (the other 2 are fats and proteins). Carbohydrates are needed to produce energy; the energy produced by carbohydrates is 4 calories per gram.

Dehydration: When the body loses too much water to work well. Severe diarrhea or vomiting can cause dehydration.

Diet: The foods you eat and drink, both liquids and solids.

Digestive tract: The parts of the body that eat, digest, and excrete food. It includes the mouth, esophagus, stomach, intestines, rectum, and anus.

Fat: One of the 3 nutrients that supply calories to the body (the other 2 are proteins and carbohydrates). The energy produced by fat is 9 calories per gram.

Fatigue: the feeling of being tired physically, mentally, and emotionally. Cancer-related fatigue persists over time and can interfere with usual activities. This fatigue is different from the fatigue of everyday life, which is usually temporary and relieved by rest.

Fatty acids: the building blocks of fats; also what the body breaks fats down into.

Fiber: The part of plant foods that the body cannot digest. Fiber helps to move food waste out of the body quickly. Fiber is found in fruits, vegetables, dry beans and peas, nuts and seeds, and breads and cereals. Fiber is not found in animal foods (meat, milk, and eggs).

Fluids: Liquids.

Free radicals: Highly reactive oxygen-free compounds created during normal cell metabolism which can damage important cell proteins and enzymes and can even cause DNA changes that can cause cancer.

Gastrostomy: Surgical placement of a tube through the skin into the stomach for liquid feedings through the tube. Also called a G-tube.

Jejunostomy: Surgical placement of a tube through the skin into the intestine for liquid feedings through the tube. Also called a J-tube.

Minerals: Nutrients needed in small amounts by the body to help it function properly and stay strong. Iron, calcium, potassium, and sodium are examples of minerals.

Nutrients: Chemical compounds (water, protein, fats, carbohydrates, vitamins, and minerals) that make up foods.

Nutrition: A 3-part process that gives the body the nutrients it needs. First, you eat or drink food. Second, the body breaks the food down into nutrients. Third, the nutrients travel through the bloodstream to different parts of the body where they are used as "fuel" and for many other purposes. To give your body proper nutrition, you have to eat and drink enough of the foods that contain key nutrients.

Phytochemical: See phytonutrient.

Phytonutrient: Plant compounds such as carotenoids, limonoids, and phytosterols that are thought to have health-protecting qualities.

Proteins: One of the 3 nutrients that supply calories to the body (the other 2 are fats and carbohydrates). The protein we eat becomes a part of our muscle, bones, skin, and blood. The energy produced by proteins is 4 calories per gram.

Registered dietitian: A health care professional with extensive scientific background in food, nutrition, biochemistry, and physiology. This knowledge is applied to promoting health and preventing disease through counseling and education.

Sodium: A mineral your body needs to keep body fluids in balance. Sodium is found in table salt. Too much sodium can cause you to retain water.

Total parenteral nutrition (TPN): Delivery of nutrients directly into the bloodstream through a needle that is put into a vein.

Tube feeding (enteral nutrition): A small, thin, flexible tube is placed into the nose and threaded into the stomach to provide liquid nutrients when a person cannot eat enough. The tube can also be placed surgically into the stomach (see gastrostomy) or intestine (see jejunostomy).

Vitamins: Key nutrients, such as vitamins A, C, and E, that the body needs in small amounts to grow and stay strong. Most can be found naturally in foods. There are also supplements in pill and liquid form.

Whole grain: Whole grains or foods made from them contain all the essential parts and naturally-occurring nutrients of the entire grain seed. If the grain has been processed (for example, cracked, crushed, rolled, extruded, lightly pearled and/or cooked), the food product should give you about the same rich balance of nutrients that are found in the original grain seed. Whole grain types include wheat, oats, corn, and rye along with lesser-known grains like barley, spelt, groats, wheat berries, millet, and flaxseed. Whole grains are found in cereals, breads, flours, and crackers and some whole grains can be used as side dishes or part of an entree. Find whole grains by checking the package label for the words "whole" or "whole-grain." Phrases like "stoned wheat," "cracked wheat," and "wheat flour" don't guarantee the presence of whole grain.

Revised: 02/04/2008