main source of energy. Carbs turn into sugar and are called “starches”. Cheaper source of energy than are proteins and fats. Easily digested, grow well in most climates, and keep well without refrigeration. Made of carbon, hydrogen, and oxygen.
• Cellulose: fibrous, indigestible form of carbohydrate. Provides bulk in the digestive tract and causes regular bowel movements.
Lipids; provide source of energy and are for insolation and body temperature. Classified as saturated or polyunsaturated. Provide most concentrated form on energy, but are most expensive source of energy. Also maintain body temperature by providing insulation; cushion organs and bones; aid in the absorption of fat-soluble vitamins; and provide flavor to meals.
• Cholesterol: fatty substance found in body cells and animal fats.
basic components of all body cells, essential for building and repairing tissue, regulating body functions, and providing energy and heat. Essential for building and repairing tissue, regulating body functions, and providing energy and heat. Made of carbon, hydrogen, oxygen, and nitrogen, and some contain sulfur, phosphorus, iron, and iodine. Made of “amino acids”. Proteins that contain nine of the amino acids are called “complete proteins”. Proteins that contain any remaining thirteen amino acids are called “incomplete proteins”.
organic compunds that are essential to life. Important for metabolism, tissue, building, and body process regulation. Allows body to use the energy provided by carbohydrates, fats, and proteins. Usually classified as water soluble or fat soluble.
• Water soluble: vitamins dissolve in water, not normally stored in the body, and easily destroyed by cooking, air, and light.
• Fat soluble: vitamins dissolve in fat, can be stored in the body, not easily destroyed by cooking, air, and light.
inorganic (nonliving) elements found in all body tissues. Regulate body fluids, assist in various body functions, contribute to growth, and aid in building tissues.
found in all body tissues. Essential for the digestion (breakdown) of food, make up most of the blood plasma. Helps body tissues absorb nutrients, and helps move waste material through the body. The average person should still drink six-eight glasses of water each day to provide the body with the water it needs.
the process by which the body breaks down food into smaller parts, changes the food chemically, and moves the food through the digestive system. Two types of digestive action are;
• Mechanical: food is broken down by the teeth and moved through the digestive tract by a process called “peristalsis” (a rhythmic, wavelike motion of the muscles)
• Chemical: food is mixed with digestive juices secreted by the mouth, stomach, small intestine, and pancreas.
Digestive juices contain enzymes, which break down the food chemically so the nutrients can be absorbed into the blood.
process in which blood capillaries pick up the digested nutrients. Nutrients are carried by the circulatory system to every cell in the body. Absorption mostly occurs in the small intestine, but water, salts, and some vitamins are absorbed in the large intestine.
process in which nutrients are used by the cells for building tissue, providing energy, or regulating various body functions. The nutrients are combined with oxygen, energy and heat are released. Rate, at which the body uses energy just for maintaining its own tissue, without doing any voluntary work, is called “basal metabolic rate, BMR”. The body stores nutrients for future use and these stored nutrients are used to provide energy when food intake is not adequate for energy needs.
Measuring Food Energy
amount of heat produced during metabolism is the way the energy content of food is measured. The heat is measured by a unit called “kilocalorie (kcal) or calorie”. The number of kilocalories in a certain food is known as that foods “caloric value”.