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Discover the science of nutrition and its vital role in health and disease. Learn about essential nutrients, body composition, and nutrient classification. Explore the importance of carbohydrates, lipids, proteins, vitamins, minerals, and water for optimal health.
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Nutritional Goals • Quality intake that allows you to function at your best and promotes health. • Intake that provides adequate levels of each nutrient • Quantity of intake that promotes a healthy body weight.
Nutrition Defined • Nutrition – the science that links foods to health and disease • Study processes by which nutrients are • Ingested • Digested • Absorbed • Transported • Metabolized • Excreted
What’s Considered Food? • Foods contain nutrients and are derived from plant or animal sources • Nutrients – substances in foods that are needed for growthand maintenance of a heathy body • ~ 40 nutrients identified at this time
Essential Nutrients • To be classified as an essential nutrient: • The biological function of nutrient is known • Omission from the diet leads to a decline in a biological function • Return of the nutrient before permanent damage is done restores the biological function
Classifying Nutrients • Essential nutrients– another way to think about… • nutrients the body either cannot make or cannot make enough of to maintain health • These nutrients must be obtained from foods (ingested in some manner) • Examples: • Vitamins • Calcium, iron, and other minerals • Some of the amino acids
Classifying Nutrients • Nonessential nutrients– body can make from other nutrients ingested Examples: • Cholesterol • Some amino acids
Classifying Nutrients There are 6 Classes of Nutrients 1. Carbohydrates 2. Lipids (fats) 3. Proteins 4. Vitamins 5. Minerals 6. Water
Describing the Nutrients • There are several ways to classify the 6 classes of nutrients. • Essential or nonessential • Organic or inorganic • Macronutrient or micronutrient • Energy yielding or not • Promote growth, development, maintenance • Regulate body functions
Classifying Nutrients by Composition • Organic nutrients - contain carbon • Carbohydrates • Lipids • Proteins • Vitamins • Inorganic nutrients - do not contain carbon • Minerals • Water
Quantity Needed • Macronutrients: need in relatively large amounts • Carbohydrates, lipids, proteins • Micronutrients: need in relatively small amounts • All other nutrients
Classifying Nutrients • Energy-yielding nutrients (3): • Carbohydrates • Fats (lipids) • Proteins
Nutrients 1. Carbohydrates: C, H, O • 4 kcal/gram • Body’s primary source of energy • Use as glucose • Glucose is the brain’s only source of energy • Carbohydrate stores are limited ~12-24 hours (in liver and muscle)
Classes of Carbohydrates • Simple sugars • Monosaccharides and disaccharides • Complex carbohydrates • Starch • Fibers – cannot be digested, pass through system
Carbohydrate rich foods? • Simple • Complex • Fiber
Lipids 2. Lipids – fats and oils: C, H, O • 9 kcal/gram • Body’s alternate source of energy • Use fat along with glucose as an energy source most of the time • Stores are unlimited
Types of Lipids • Fats • Solids at room temperature • Mostly animal sources • Animal sources of fats contain the lipid cholesterol • Associated with health issues • Oils • Liquids at room temperature • Plant sources, fish oils • Contain essential fatty acids
Other Lipids • Cholesterol • Non-essential nutrient • Animal sources only • Associated with cardiovascular disease • Trans fats • Made when unsaturated oils are processed • Hydrogenation reaction makes trans fats • Associated with health issues
Proteins • Proteins: C, H, O, N, S • Primary function is structural • Muscles, bones, hair, antibodies, hemoglobin, enzymes….. • 4 kcal/gram (same as _______) • Body’s least desirable source of energy • Protein is used for energy only when carbohydrate is NOT available as an energy source.
Classes of Proteins • Proteins are made of ~20 amino acids • 9 of these are essential • Complete proteins – contain all 9 essential amino acids • Incomplete proteins – lacking one of more essential amino acids
Protein Rich Foods? • Animal proteins • Source of complete protein • Meat, poultry, fish, eggs, dairy • Plant Proteins • Source of incomplete protein • Grains, beans (legumes), nuts, seeds, some vegetables
6 Classes of Nutrients • Carbohydrates • Lipids (fats and oils) • Proteins • Vitamins • Minerals • Water
Vitamins • Essential • Organic, micronutrient • Not energy-yielding (no calories) • 2 classes of vitamins: • water-soluble • fat-soluble
Minerals • Essential • Inorganic, micronutrient • Major minerals: eg..Ca, P, Na • Trace minerals: eg…Fe, Zn • Not energy-yielding • Indestructible, can be lost in cooking water • Structural functions, some are electrolytes – play role in muscle and nerve function
Water • Water (H2O) • Essential • Organic or inorganic? • Noncaloric • We are ~60% water
Other Components of Foods • Phytochemicals – chemicals found in plants that are associated with health • Not considered essential nutrients • See page 14
Energy-Yielding Non-nutrient • Alcohol – 7 kcal/gram • Not an essential nutrient because it does not have any required functions in the body
A little more on energy • Where does the energy come from? • Measure energy in kilocalories in U.S. • What most think of as a “calorie” is really a kilocalorie • Kcal = amount of energy needed to raise the temperature of 1 kg of water by 10C • Measure energy in kilojoules (kJ) in most other countries
Energy in the Body • The body uses the energy yielding nutrients to fuel all activities • All energy yielding nutrients are “caloric”. • If more energy is ingested than is needed to fuel body activities the extra energy is stored as _________ and ________ occurs.
Evaluating a Food Label • _____ grams carbohydrate • _____ grams fat • _____ grams protein • TOTAL KCAL: ____________
Diet and Health • Diet - the foods one consumes • The quality of your daily diet affects the risk of chronic diseases • Meaning…..The food choices you make daily have a cumulative impact on your health
Nutrition and Health • Chronic health issues associated with diet include: • Heart disease • Hypertension • Obesity • Type II Diabetes • Osteoporosis
Improving your Health • Goal is to reduce the number of risk factors that are in your control • Risk factor = something that statistically increases the incidence of a disease • Risk factors may not be the cause of the disease
Leading Causes Death - U.S. (2014) • Heart disease: 614,348 • Cancer: 591,699 • Chronic lower respiratory diseases: 147,101 • Accidents (unintentional injuries): 136,053 • Stroke (cerebrovascular diseases): 133,103 • Alzheimer's disease: 93,541 • Diabetes: 76,488 • Influenza and pneumonia: 55,227 • Kidney disease: 48,146 • Intentional self-harm (suicide): 42,773
Obesity in the United States • Obesity plays a role in chronic health issues • Diabetes • Heart disease • Stroke • Hypertension • Some cancers • High cholesterol
Improving Health • Risk factors you cannot control: • Age • Gender • Genetics (family history) • Ethnicity
Improving Health • Risk factors in your control: • Smoking • Alcohol intake • Over-consumption of calories • Physical inactivity • Poor quality diet
Healthy People 2020 • Focuses on: • Healthy eating patterns • Healthy physical activity patterns • Healthy weight
Healthy People 2020 • Americans with a healthful diet: • Consume a variety of nutrient-dense foods within and across the food groups, especially: • whole grains, fruits, vegetables, low-fat or fat-free milk or milk products, and lean meats and other protein sources.
Healthy People 2020 • Americans with a healthful diet: • Limit the intake of saturated and trans fats, cholesterol, added sugars, sodium (salt), and alcohol.
Food Choices • Small group exercise • What influences your food choices each day? • Why do you eat what you eat? • Get into groups of ~4 and make a list of what impacts your food choices most days.
Personal preferences Habit Ethnic heritage Tradition Social interactions or pressure Availability Convenience Economy $ Positive or negative associations Emotional Comfort Values -Religious, political, environmental Health concerns Nutritional value Food marketing Food Choices – see page 5 for text’s answers