Nutrition Glossary (cont.)
Electrolytes: These are nutrients that affect fluid balance in the body and are necessary for our nerves and muscles to function. Sodium and potassium are the two electrolytes most often added to sports drinks. Generally, electrolyte replacement is not needed during short bursts of exercise since sweat is approximately 99% water and less than 1% electrolytes. Water, in combination with a well-balanced diet, will restore normal fluid and electrolyte levels in the body. Replacing electrolytes may be beneficial during continuous activity of longer than 2 hours, especially in a hot environment.
Enzyme: A protein that acts as a catalyst to mediate and speed a specific chemical reaction.
Fat: 1) With proteins and carbohydrates, one of the three nutrients used as energy sources by the body. The energy produced by fats is nine calories per gram. Proteins and carbohydrates each provide four calories per gram. 2) Total fat is the sum of saturated, monounsaturated, and polyunsaturated fats. Intake of monounsaturated and polyunsaturated fats can help to reduce blood cholesterol when substituted for saturated fats in the diet.
Fatty Acids: There are three main types of fatty acids: saturated, monounsaturated and polyunsaturated. All fatty acids are molecules composed mostly of carbon and hydrogen atoms. A saturated fatty acid has the maximum possible number of hydrogen atoms attached to every carbon atom. It is therefore said to be "saturated" with hydrogen atoms.
Some fatty acids are missing one pair of hydrogen atoms in the middle of the molecule. This gap is called an "unsaturation" and the fatty acid is said to be "monounsaturated" because it has one gap. Fatty acids that are missing more than one pair of hydrogen atoms are called "polyunsaturated."
Saturated fatty acids are mostly found in foods of animal origin. Monounsaturated and polyunsaturated fatty acids are mostly found in foods of plant origin and some sea foods. Polyunsaturated fatty acids are of two kinds, omega-3 or omega-6. Scientists tell them apart by where in the molecule the "unsaturations," or missing hydrogen atoms, occur.
Fiber: The parts of fruits and vegetables that cannot be digested. This fiber is of vital importance to digestion, helping the body move food through the digestive tract, reducing serum cholesterol, and contributing to disease prevention. Also called bulk or roughage.
Fiber and cholesterol: Soluble fiber substances are effective in helping reduce the blood cholesterol. This is especially true with oat bran, fruits, psyllium and legumes. High soluble-fiber diets may lower cholesterol and low-density lipoproteins ( the 'bad' lipoproteins ) by 8% to 15%.
Folate (folic acid): Folic acid is an important factor in nucleic acid synthesis (the genetic material of all cells). Deficiency leads to megaloblastic anemia. Important as a supplement for women of childbearing age to prevent nervous system birth defects.
Food, "Super":Foods with alleged healing or health-promoting capabilities. The healing power of foods is a popular concept. Medicinal or nutritionally high- powered foods have been part and parcel of the natural products industry for a long time and, through emerging scientific research and particularly through growing public interest, they have reached the mainstream. Not all items advertised as "super" foods or healing foods have been proven to promote health, however, and some may be contraindicated for people with certain health conditions. Before making drastic changes to your diet, always consult with your physician or a professional nutritionist.
Functional foods: As defined by the Institute of Medicine in Washington, are "those foods that encompass potentially healthful products including any modified food or ingredient that may provide a health benefit beyond the traditional nutrients it contains." Functional foods can include foods like cereals, breads and beverages which are fortified with vitamins, herbs or neutraceuticals.
Glucosamine: A molecule derived from the sugar glucose by the addition of an amino (NH2) group, glucosamine is a component of a number of structures including the blood group substances and cartilage.
Glucosamine is an unproven nutritional supplement. It has received acclaim as a "cure" for arthritis -- for which there is no evidence.
Glucosamine has also been hailed as a remedy for the relief of osteoarthritis symptoms. It may improve symptoms in selected patients with osteoarthritis, according to preliminary European studies, but definitive longterm proof is lacking. Glucosamine has not been evaluated for other forms of arthritis.
Glucosamine has been marketed as a "cartilage rebuilder" partly on the assumption that, because glucosamine is a component of cartilage, consuming it will help rebuild damaged cartilage. (The notion that glucosamine would help rebuild cartilage is analogous to the idea that eating hair will put hair back on a bald head). There is no evidence that glucosamine alone, or in combination with chondroitin, is of any value in rebuilding cartilage.
Glucose: The sugar that is the chief source of energy. Glucose is considered a simple sugar. Found in the blood, it is the main sugar that the body manufactures. The body makes glucose from all three elements of food-protein, fat and carbohydrates-but in largest part from carbohydrates. Glucose serves as the major source of energy for living cells. It is carried to each cell through the bloodstream. Cells, however, cannot use glucose without the help of insulin. Glucose is also known as dextrose.