Chapter 1 What is Nutrition Science that studies food in how it nourishes our bodies and influences our health Includes studying our eating patterns making recommendations Identifies how we consume digest metabolize and excrete nutrients Nutrients Organic v Inorganic o Organic Contain carbon and hydrogen Carbohydrates lipids proteins vitamins o Inorganic Not contain carbon and hydrogen Minerals water Macronutrient v micronutrient o Macronutrient Body requires in relatively large amounts Carbohydrates lipids proteins o Micronutrients Nutrients needed in relatively small amounts Vitamins and minerals Fat soluble v water soluble o Fat soluble Vitamins A D E K Stored in body o Water soluble Vitamin C and the B vitamins B12 only one stored in the body Energy yielding nutrients o Lipids 9 kcal g o Protein 4 kcal g o Carbohydrates 4 kcal g o Alcohol 7 kcal g DRI s apply to healthy adults Dietary reference intakes DRIs o Consists of EAR RDA AI UL Recommended Dietary Allowance RDA o Average daily nutrient intake level that meets the needs of 97 98 of healthy people in a particular life stage and gender group Estimated average requirement EAR o Average daily intake level of a nutrient to meet the needs of half of the healthy people in a particular life stage or gender group o Used to define the RDA of a nutrient Tolerable Upper Intake Level UL o Highest average daily nutrient intake level likely to pose no risk of adverse health effects to most people o Consumption of a nutrient at levels above the UL increases the potential for toxic effects and health risks increases Estimated Energy Requirement EER o Average dietary energy intake to maintain energy balance in a healthy adult o Defined by age gender weight height and level of physical activity Acceptable Macronutrient distribution range AMDR o Ranges of energy intakes from macronutrients that are associated with reduced risk of chronic disease while providing adequate intakes of essential nutrients o If nutrient intake falls outside this range there is a potential for increasing our risk for poor health Chapter 2 What are the tools used to assist in designing a healthful diet Food labels 2010 dietary guidelines for Americans USDA Food Patterns MyPlate Nutrient Density Relative amount of nutrients per amount of energy number of calories What are the recommendations of the Dietary guidelines for Americans and MyPlate Balance Calories to maintain weight Consume fewer foods of concern Consume more healthful foods nutrients Follow healthy eating patterns What is a chronic disease A long lasting condition that can be controlled but not cured Ex diabetes heart disease Chapter 13 Healthy Body weight Body Mass Index Expresses the ratio of a person s weight to the square of his or her height o Weight kg height m 2 Normal BMI 18 5 25 kg m2 healthy Underweight BMI 18 5 may have an eating disorder or genetically tiny Overweight BMI 30 Components of Energy Expenditure Basil Metabolic rate majority of calories burned by this Thermic effect of food TEF o Energy expended to process food o About 5 10 of energy content of a meal Energy cost of physical activity o About 15 35 of total daily energy output o Energy expended on body movement muscular work Chapter 13 5 Eating Disorders Anorexia Nervosa o Restrictive eating that leads to self starvation o Fear of weight gain trigger stress and anxiety o Causes Amenorrhea condition of having no menstrual periods for at least 3 continuous months Bulimia Nervosa o Characterized by repeated episodes of binge eating followed by some sort of purging o Symptoms chronically inflamed sore throat swollen glands in neck above jaw worn tooth enamel gastroesophageal reflux disorder intestinal distress and irritation from laxative abuse kidney problems from diuretic abuse sever dehydration Binge Eating o Characterized by binge eating an average of twice a week or more typically without compensatory purging Night Eating o Characterized by intake of the majority of the day s energy between 8 pm and 6 am o Mood and sleep disorders also common with this disorder Chapter 4 5 7 alcohol Alcohol abuse Liver damage irreversible Bone health Pancreatic injury and diabetes Cancer Alcohol oxidation steps Small amount oxidized in stomach before being absorbed into the bloodstream o Gastric ADH reduces absorption of alcohol Most alcohol absorbed into bloodstream and transported to the liver In the liver the ADH pathway dominates lower intakes of alcohol and the MEOS pathway is important in higher intakes Moderate alcohol consumption According to Dietary Guidelines for Americans o 1 drink per day for women o 2 drinks per day for men Metabolic tolerance Liver becomes more efficient in its breakdown of alcohol BAC rises more slowly after drinking Functional tolerance Individuals show few signs of impairment intoxication even at high BAC Chapter 3 Hunger appetite Hunger o Physiological drive for food o Nonspecific satisfied by variety of foods o Triggered by hypothalamus Appetite o Psychological desire to consume specific foods o Aroused by environmental cues Hormones regulate appetite Pancreatic hormones insulin and glucagon maintain blood glucose levels Feeling full satiated results from signals from the stomach and a rise in blood glucose CCK cholecystokinin signals the gallbladder to release bile Accessory organs of digestion Gallbladder Pancreas Liver Absorption Process of taking molecules across a cell membrane and into cells of the body Digestion Large food molecules are broken down to smaller molecules mechanically and chemically Elimination Undigested portions of food and waste products are removed from the body Segmentation Rhythmic contraction of circular muscles in the intestinal walls Mixes the chime and enhances its contact with digestive enzymes and enterocytes 4 types of absorption Passive diffusion o Nutrients simply pass through the enterocytes and into the bloodstream without the use of a carrier or energy Facilitated diffusion o Requires a carrier protein Active transport o Requires energy and a protein carried to transport nutrients Endocytosis pinocytosis o Active transport by which a small amount of intestinal contents is engulfed by the cell membrane into the cell Chapter 4 Smallest molecules that makes up carbohydrates are called monosaccharides Carbohydrate digestion Begins in the mouth Salivary amylase breaks carbohydrates down to maltose Most chemical digestion occurs in small intestine Ketosis Caused by a diet
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