Download Chapter Twelve – Food and Nutrition

Chapter Twelve – Food and Nutrition
Your Nutritional Needs
Food and Energy
 Your body needs food, and food affects your health in many ways
1. How you look and feel
2. How you resist disease
3. How you perform physically and mentally
 Food provides your body nutrients – the substances that the body needs
to regulate bodily functions, promote growth, repair body tissue, and
obtain energy
 You body requires over 40 different nutrients for these tasks
 Nutrition is the process in which the body takes in and uses these
nutrients
 When your body uses nutrients, chemical reactions take place in your
cells and energy is released
 Metabolism is the chemical process by which your body breaks down food
to release as energy
 Metabolism involves the use of energy and material for growth and repair
of bodily tissues
Six basic Nutrients
1. Carbohydrates
 Two types of carbohydrates: simple and complex
 Simple carbos consist of sugar, but glucose is most important
 Glucose is the major provider of energy for your body
 Glucose is a simple sugar that is produced when you eat complex
carbohydrates.
 When you eat, you eat more glucose than your body can use, it is stored
as glycogen – stored starch/sugar in your body.
 All other types of sugars are converted to glucose after they enter your
body (ex. fruits, vegetables, milk, cookies, candy, and soft drinks)
 Complex carbos are made up of sugars that are linked together to form
chains
 Starch is a main complex carbohydrate found in plant foods like potatoes,
grains, and fiber
 Fiber is the part of grains and plant foods that cannot be digested.
 Fiber also is known as roughage, helps move food through the digestive
system.
 There are two types of fiber:
1. Insoluble fiber helps prevent constipation and is associated with
reduced risk of colon cancer.
2. Soluble fiber reduces your blood cholesterol level and your risk of
developing heart disease
2. Fats
 Nutrient with the highest energy content
 Fats supply body with energy and form part of cell walls
 Necessary for healthy skin and hair
 Two types of fats: saturated and unsaturated
 Unsaturated fats (poly and mono) are usually liquid at room temperature
 Most vegetable oils, nuts, and seed are unsaturated fats
 Saturated fats exist in animal fat like beef, chicken, pork, lamb, and dairy
products
 Usually solid at room temperature
 Saturated fats can affect the amount of cholesterol – the waxy, fatlike
substance found in the cells of all animals – in your blood
 Elevated cholesterol levels are linked to heart disease
Trans-fatty acids
 Trans-fatty acids are fatty acids that are formed when vegetable oils
are processed into solid fats, such as margarine or shortening.
 Hydrogenation is the process of converting vegetable oils into solid
fats.
 Trans-fatty acids appear to raise blood cholesterol levels.
3. Proteins
 Can serve as a source of energy
 The really important function of proteins is the growth and repair of body
tissues
 High protein foods include: milk/milk products, meats, eggs, poultry,
cheese, nuts, beans, peas, and lentils
 Your body has 20 Amino Acids, 9 are called essential – very important amino acids and come from animal sources
 A complete protein is a protein that contains all of the essential amino
acids.
 An incomplete protein is a protein from plant sources that does not contain
all of the essential amino acids.
4. Vitamins
 Nutrients that are made by living things, and are required in small
amounts, and assist chemical reactions
 Vitamins do not directly provide your body with energy or raw materials to
make cells
 Vitamins help with the processes of your body, such as the breakdown of
nutrients
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Some occur naturally – vitamin C from the sunlight, but most must be
supplied in food you eat
Two classes of vitamins: Fat-Soluble and Water Soluble
Fat soluble vitamins dissolve in fat; Vitamins A, D, E, K
Water soluble vitamins dissolve in water; Vitamins C and all of Vitamin B
Vitamin deficiency is a condition in which a person does not obtain enough
of a specific nutrient
5. Minerals
 Nutrients that are not manufactured by living things
 Minerals occur naturally in rocks and soil
 Plants absorb the minerals, animals eat the plants, we eat the plants and
animals
 There are 24 essential minerals for good health
 Our body needs 6 of them, calcium, magnesium, phosphorus, sodium,
potassium, and chlorine, in different amounts
 Calcium is important in blood clotting and CNS, as well as bone growth
 Iron is necessary for healthy red blood cells (girls and women needs lots)
 Anemia – a lack of sufficient iron in one’s body, making them tired, weak,
and easily sick
6. Water
 About 65 percent of your body weight is water
 Water is essential for all life processes
 Water
1. Is primary component of blood
2. Helps create new tissues
3. Helps produces energy
4. Carries waste out of body
5. Regulates body temperature
 Water contains electrolytes that regulate many processes in cells
 Humans need approximately 8 cups (2 liters) of water per day
 Dehydration results from not having enough water in your body
 Symptoms of dehydration include weakness, rapid breathing, and weak
heartbeat