Nutrition Health 12

10/17/07 DO NOW: What Do You Know about Healthful Eating? On Page 109 of your textbook, answer the “Myth or Fact” questions in your notebook. You do not need to write out the questions.

Focus of Nutrition The area of health that focuses on: Selecting foods that contain nutrients Eating the number of recommended servings from the Food Guide Pyramid Following Dietary Guidelines Planning a healthful diet that reduces the risk of disease

Focus of Nutrition Evaluating food labels Developing healthful eating habits Protecting against food-borne illnesses Maintaining a desirable weight and body composition

Selecting Foods that Contain Nutrients Nutrient – A substance in food that helps with body processes, helps with growth and repair of cells, and provides energy There are 6 basic classes of Nutrients Energy is measured in calories Calorie – unit of energy produced by food and used by the body

Classes of Nutrients No one food contains all the nutrients needed for health Basic classes of nutrients: Proteins Carbohydrates Fats Vitamins Minerals Water

Protein Protein is a nutrient needed for: Growth Building, Repairing, and Maintaining body tissues Supplying Energy Helps the body maintain strength and resist infection Proteins form part of every cell in the body & make-up more then 50% of total body weight

Protein (cont.) Each gram of protein provides 4 calories of energy Diets deficient in protein can: Stunt a person’s growth Impair the development of certain tissues Impair mental development Excess protein is burned as energy or stored as fat Overeating Proteins Two types of proteins: Complete Proteins Incomplete Proteins

Complete Protein Complete Protein is a protein that contains all of the essential amino acids Amino Acids – the building blocks that make up proteins The body needs 20 amino acids to function properly (the body can produce 11 of these) Sources: Meat, Fish, Poultry, Milk, Yogurt, Eggs, and Soybeans Essential Amino Acids – the 9 amino acids the body cannot produce These must come from the foods we eat

Incomplete Protein An incomplete protein is a protein that does not contain all of the essential amino acids Come from plant sources: Grains (whole Grains, pastas, and corn) Legumes (dried beans, peas, lentils) Nuts and Seeds Combining different plant sources of incomplete proteins can provide all of the essential amino acids

Carbohydrates Carbohydrates – main source of energy for the body Include sugars, starches, and fiber Supply 4 calories of energy per gram of food Body can only store limited amounts of carbohydrates Excess carbohydrates converted and stored as fat

Carbohydrates (cont.) Sources of Carbohydrates: Vegetables, beans, potatoes, pasta, breads, rice, bran, popcorn, and fruit Types of Carbohydrates: Simple Carbohydrates Complex Carbohydrates

Simple Carbohydrates Simple Carbohydrates are sugars that enter the bloodstream rapidly and provide quick energy Found naturally in fruits, honey, and milk Processed sugar (table sugar) is added to many foods during processing (sweets, ketchup, sauces, soda) Provide calories but few vitamins and minerals

Complex carbohydrates Complex carbohydrates are starches and fiber Sources: grains (breads/pasta), vegetables (potatoes/beans) Starch – food substance that is made and stored in most plants Fiber – the part of grains and plant that cannot be digested Good for Digestion Makes you feel full Reduces cholesterol and risk of heart disease Sources: wheat, bran, cereals, fruit, vegetables

Carbohydrates (cont.) Carbohydrates are converted to glucose (simple sugar) Used for energy Excess converted to glycogen, stored in muscles (converted back to glucose when needed for energy)

Fats A Fat is a nutrient that provides energy and helps the body store and use vitamins 1 gram of fat supplies 9 calories of energy Store and transport fat-soluble vitamins Fat Soluble Vitamins – vitamins that dissolve in fat and can be stored in the body Include Vitamins A, D, E, and K

Fats (cont.) Fats are stored as fat tissue that surrounds and cushions internal organs They contribute to the taste and texture of many foods Fats are needed for: Maintaining body heat Store and use vitamins Maintaining an energy reserve Build brain cells and nerve tissues

Fats There are two main types of fats: Saturated Fats Unsaturated Fats Saturated Fats – A type of fat from dairy products, solid vegetable fat, and meat and poultry Usually in solid form when at room temperature Contribute to the level of cholesterol that is in a person’s blood Cholesterol – A fat-like substance made by the body and found in certain foods Dietary Cholesterol – Cholesterol in food Found in foods of animal origins (Meats, Dairy Products) Blood cholesterol level is combination of the dietary cholesterol and cholesterol produced by the body

Fats (cont.) Dietary Cholesterol: Found in foods of animal origins (Meats, Dairy Products) Blood cholesterol level is combination of dietary cholesterol and cholesterol produced by the body Prevention of high blood cholesterol levels: Eat fewer saturated fats Reduce the risk of heart disease and some cancers

Unsaturated Fats Unsaturated Fat – Obtained from plant products and fish and is usually liquid at room temperature Two types of unsaturated fats: Polyunsaturated Fats (sunflower, corn, and soybean oils) Monounsaturated Fats (olive oil, canola oil)

Fats (cont.) Visible Fat – Fat that can be seen when looking at food Invisible Fat – Fat that cannot be seen when looking at food (ex: the eggs and shortening in a piece of cake) Trans Fatty Acids – produced when polyunsaturated fats are hydrogenated Raise cholesterol and contribute to other health problems

Vitamins Vitamin – A nutrient that helps the body use carbohydrates, proteins, and fats Do not supply energy Needed for a balanced diet Two types of Vitamins: Fat-soluble Water-soluble

Types of Vitamins Fat-soluble vitamins – a vitamin that dissolves in fat and can be stored in the body There are 4 fat-soluble vitamins: A, D, E, K Stored primarily in the liver Water-soluble vitamins – a vitamin that dissolves in water and cannot be stored in the body Examples: B complex, Vitamin C

Vitamin Deficiencies Those who do not eat a balanced diet may develop vitamin deficiencies Vitamin C deficiency – Symptoms: Loosened teeth and gum disease Vitamin D deficiency – Symptoms: Rickets, poor teeth, soft bones in adults Rare in US – most common in underdeveloped countries Foods are the best source of nutrients

Minerals Mineral – a nutrient that regulates many chemical reactions in the body Two types of Minerals: Macro Minerals (calcium, sodium) Required in amounts greater then 100mg Trace Minerals (iron, zinc) As important to the body as macro minerals

Minerals (cont.) Iron – an important component of hemoglobin and functions as a carrier of oxygen in the body Iron deficiency can lead to anemia Condition in which the body is unable to produce sufficient red blood cells A person who does not get enough iron: Susceptible to illnesses and infection Poor appetite Feel weak Continually tired Decrease in the body’s ability to transport oxygen

Minerals (cont.) Calcium – needed for building bones and teeth maintains bone strength Functions in the contraction of muscles and in blood clotting Sources: Milk and milk products, dark green leafy vegetables, calcium fortified orange juice, dried beans

Sodium Sodium – regulates and maintains the balance of fluids in the body Source: table salt Occurs naturally in many foods and added to many processed foods Extra salt is not needed to maintain adequate intake

Water Water – a nutrient that is involved with all body processes Makes up the basic part of the blood Helps with waste removal Regulates body temperature Cushions the spinal cord and joints Makes up more then 60% of body mass Carries nutrients to all body cells and waste products from the cells to the kidneys

Water (cont.) Water leaves the body through perspiration and urine People can only survive 3 days without water Dehydration – a condition in which the water content of the body has fallen to a low level