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Understanding Nutrition and Your Diet. Chapter 5. Nutrients = elements in food that are required for the growth, repair, and regulation of body processes Carbohydrates Fats Protein Vitamins Minerals Water Fiber. Nutrients. Energy from Food. Calorie = unit of energy
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Understanding Nutrition and Your Diet Chapter 5
Nutrients = elements in food that are required for the growth, repair, and regulation of body processes Carbohydrates Fats Protein Vitamins Minerals Water Fiber Nutrients
Energy from Food Calorie = unit of energy • 1 calorie = amount of energy needed to raise the temperature of 1 gram of water by 1 degree Celsius • In common usage, “calorie” refers to “kilocalorie” (1,000 calories)
Carbohydrates • Major energy source: 4 calories/gram • Types • Monosaccharides • Disaccharides • Polysaccharides • Recommended intake: 45-65% of total calories from carbohydrates
Carbohydrates • Simple sugars • Average American adult consumes about 140 pounds of sweeteners each year • Sugar, corn sweetener, syrup, honey • Sodas, candy, bakery and processed goods • Sugar substitutes • Saccharin • Aspartame • Sucralose, tagatose • Sorbitol, xylitol • Acesulfame potassium • Neotame
Fats • Functions: Insulation, carrier of vitamins, storage of long-term energy, and satiety • Energy source: 9 calories/gram • Types • Saturated • Monounsaturated • Polyunsaturated • Trans • Recommended intake: 20-35% of total calories
Saturated fats Solid at room temperature Primarily found in animal fats Negative effects on heart health Monounsaturated and polyunsaturated fats Liquid at room temperature Vegetable oils Positive effects on heart health Omega-3 polyunsaturated fats found in fish are considered especially healthful Types of Fats
Types of Fats: Trans Fats • Altered form of unsaturated fat (hydrogen added) • Associated with unhealthy changes in cell membranes • Raises levels of “bad” cholesterol and lowers levels of “good” cholesterol • Found in margarine, snack foods, and some deep fried fast foods • Check food labels
Types of Fats: Cholesterol • White fatlike substance found in cells of animal origin • Functions: Synthesizes cell membranes; starting material in formation of hormones and bile • The liver can synthesize cholesterol • Excess cholesterol in the body can clog arteries and increase risk of cardiovascular disease
Low-fat does not necessarily mean low-calorie Higher price tag Low-fat dairy and salad dressings have less saturated fat Simplesse, Olestra Fats cannot be broken down and absorbed by body Unpleasant side effects Fats Low-fat foods Fat substitutes
Fats: General Recommendations • 20-35% of total daily calories from fat • Less than 10% of calories from saturated fat • Less than 300 mg/day of cholesterol • Keep trans-fatty acid consumption as low as possible • Get most fats from sources of unsaturated fats • Fish • Nuts • Vegetable oils
Protein • Functions: Growth and maintenance of tissue, acid-base balance • Energy source: 4 calories/gram • Amino acids = building blocks of protein • 11 can be built by the body • Nonessential amino acids • 9 must be obtained from food • Essential amino acids
Protein • Complete protein sources supply all essential amino acids • Animal foods, soybeans • Incomplete protein sources supply some but not all essential amino acids • Plant foods • Recommended intake: 10-35% of total calories
Vitamins • Organic compounds needed in small amounts for normal growth, reproduction, and maintenance of health • Serve as co-enzymes • Provide no energy: 0 calories/gram • Types • Water soluble • B-complex vitamins and vitamin C • Fat soluble • Vitamins A, D, E, K
Vitamins: Should I Take a Supplement? • Following dietary recommendations would allow most Americans to meet their nutrient needs without supplements • Many people eat too many nutrient-deficient foods • Caution with using supplements • Hypervitaminosis = toxicity • Megadoses of any vitamin can be harmful • Recommendations for certain groups • Folic acid, vitamin B-12, vitamin D
Phytochemicals • Phytochemicals = physiologically active components of foods that may deactivate carcinogens • Many phytochemicals function as antioxidants • May protect cells from damage caused by unstable molecules (“free radicals”) • Examples • Carotenoids • Polyphenols • Allyl sulfides
Minerals • Inorganic materials that act as structural elements and regulators of numerous body processes • Provide no energy: 0 calories/gram • Types • Macronutrients: “Major minerals” found in high amounts in the body • Micronutrients: “Trace elements” found in small amounts in the body
Water and Fluids • Average adult loses about 10 cups of water per day • Urination, bowel movements, breathing, perspiration • Functions: Provide medium for nutrients, waste transport, temperature control • For every pound of body weight, you need about 0.5 ounce of fluid • Sources: Beverages, fruits, vegetables
The six Classifications of Nutrients • Vitamins • Minerals • Water • Protein • Carbohydrates Sugars Starches • Fats Cellulose
Calories per gram: Protein 1 Gram = 4 calories Carbohydrates 1 Gram = 4 calories Fat 1 Gram = 9 calories Generally speaking, You need to have save about 3000 Calories (kcals) In order to lose a pound of weight
Variables which affect nutrient needs: 1. Age 2. Gender 3. Activity Level 4. Climate 5. Health 6. State of nutrition
Trans fats review triglyceride
Fiber • Cellulose-based plant material that cannot be digested • Provides no energy: 0 calories/gram • Types: • Soluble (gel-forming) • Insoluble (absorbs water) • Benefits • Moves stool through digestive tract • Lowers blood cholesterol levels • Steadies blood sugar levels • Recommended: 21-38 grams/day • Most American adults: 11 grams/day
Dietary Reference Intakes • Dietary Reference Intakes (DRIs) = recommended nutrient intakes • Estimated Average Requirement (EAR) • Recommended Dietary Allowance (RDA) • Tolerable Upper Intake Level (UL) • Acceptable Macronutrient Distribution Range (AMDR)—percent of total daily calories • 45-65% as carbohydrate • 20-35% as fat • 10-35% as protein
Tools for Planning a Healthy Diet • The USDA Food Guide: MyPyramid • The Dietary Guidelines for Americans
MyPyramid • Personalized approach • Amounts recommended from each food group vary based on age, gender, and activity level • Visit www.mypyramid.gov • Balance food intake and physical activity
MyPyramid Food Groups • Fruits • 2 cups/day for a 2,000-calorie diet • Eat a variety of fruits • Favor whole fruits over fruit juices • Vegetables • 2 1/2 cups/day for a 2,000-calorie diet • Eat a variety of vegetables • Dark green vegetables • Orange vegetables • Legumes • Starchy vegetables • Other vegetables
MyPyramid Food Groups • Milk and milk products • 3 cups/day for a 2,000-calorie diet • Favor fat-free or low-fat products • Vegans and those who are lactose intolerant should choose other sources of calcium
MyPyramid Food Groups • Meat, poultry, fish, eggs, dry beans, and nuts • 5 1/2 ounce-equivalents for a 2,000-calorie diet • 1 ounce equivalents: • 1 ounce cooked meat, poultry, fish • 1 egg • 1/4 cup legumes or tofu • 1 tablespoon peanut butter • 1/2 ounce nuts or seeds • Choose lean and low-fat foods
MyPyramid Food Groups • Breads, cereals, rice, and pasta • 6 ounces/day for a 2,000-calorie diet • 3 or more ounces/day should be whole grains • 1 ounce equivalents: • 1 slice bread • 1 cup dry cereal • 1/2 cup cooked rice, pasta, cereal
MyPyramid Food Groups • Oils (vegetable oils, fish, nuts, seeds) • 24 grams or 6 teaspoons/day for a 2,000-calorie diet • 1 teaspoon equivalents: • 1 teaspoon vegetable oil or margarine • 1 tablespoon low-fat mayonnaise • 2 tablespoons light salad dressing • Discretionary calories http://www.thecaloriecounter.com/foods/1400/14533/food.aspx
Dietary Guidelines for Americans • Adequate nutrients within calorie needs • Consume nutrient-dense foods within and among the food groups • Weight management • Balance calories from foods and beverages with calories expended • Make small decreases in calorie intake to prevent gradual weight gain over time
Dietary Guidelines for Americans • Physical activity • Regular moderate physical activity • 30 minutes/day to reduce risk of chronic disease • 60 minutes/day to prevent gradual, unhealthy weight gain • 60-90 minutes/day to sustain weight loss • Decrease sedentary activities
Dietary Guidelines for Americans • Food groups to encourage • Fruits • Vegetables • Milk • Fats • Total fat: 20-35% of total calories • Saturated fat: <10% of total calories • Cholesterol: <300 mg/day • Limit trans fats
Dietary Guidelines for Americans • Carbohydrates • Choose whole grains often • Limit added sugars • Sodium and potassium • Sodium: Consume less than 2,300 mg/day (about 1 teaspoon of salt) • Potassium: Consume potassium-rich foods such as fruits and vegetables
Dietary Guidelines for Americans • Alcoholic beverages • Those who choose to drink should do so sensibly and in moderation • Up to 1 drink/day for women • Up to 2 drinks/day for men • Food safety • Take steps to avoid microbial foodborne illness
Vegetarian Diets • Reliance on plant sources for most of the nutrients the body needs • Ovovegetarian: Includes eggs • Lactovegetarian: Includes dairy • Ovolactovegetarian: Includes eggs and dairy • Vegan: Excludes all animal products • Requires more planning • Need to maintain adequate intake of vitamin B-12, calcium, iron, zinc, vitamin D • Semivegetarian: Great reduction (but not elimination) of meat products • Pescovegetarian: Includes fish, eggs, dairy products
Nutrition and the Older Adult • Older adults may find food less tasteful, harder to chew • Lower energy requirements • Psychosocial factors • Social isolation • Depression • Alcohol consumption • Limited transportation
Required by the FDA since 1973 New in 2006 Amount of trans fat Proteins derived from major food allergen sources Food Labels
NuVal http://www.nuval.com/Shop/trading
Fast Foods • Fat density of fast foods • 40-70% of calories in fast foods is fat • Recommended intake: 20-35% of total daily calories from fat • Most people underestimate the calorie content in a fast food meal by as much as 500 calories