Exam 1 Study Guide5 Types of Scientific Studies:1. Case Studies- individuals2. Cohort Studies- a group of people3. Epidemiological Studies- populations4. Intervention Studies- include clinical trials that analyze cause and effect5. Laboratory StudiesNutrition Label: Nutrition Labeling & Education Act 1990 (NLEA)- established which foods should be labeled and standardized serving sizes by weight- Requires that label emphasizes calories, fat, cholesterol, sodium, and fiber- Vitamins: A & C- Minerals: Calcium and IronIngredients are also placed in descending order of weight on the labelClasses of Nutrients:ProteinsCarbohydratesLipids (fats)VitaminsMineralsWaterFood Energy is measured in kilocalories- The amount of heat energy needed to raise the temperate of one kilogram of water by 1 degree C is a kilocalorie and is also referred to as caloriesProteins – 4 kcal/gramCarbohydrates – 4 kcal/gramFat – 9 kcal/gramAlcohol – 7 kcal/gramVitamins, Minerals, and Water do not provide energyMeasured in:Grams – proteins, carbs, fats (lipids)Milligrams/Micrograms – vitamins and mineralsPhytochemicals- beneficial non-nutrients that some foods contain Nutrient Density = Nutrient Content / Kilocalorie ContentDietary Reference Intakes: composed of the following recommendations1. RDA: Recommended Dietary Allowances- Levels of nutrient intake adequate to meet needs of nearly all healthy people in the US- Different RDAs for different age and gender groups2. EAR: Estimated Average Requirement- The amount that meets the optimal nutrient needs of half the individuals in a specific group3. AI: Adequate Intake- Same as RDA, but lacking enough scientific evidence to set an RDA4. UL: Upper Limit - Tolerable Upper Intake Level- Total intake from food, fortified food and supplements should not exceed this amount or diverse health effects may resultDietary Guidelines:1. Purpose: to provide science-based advice for ages 2 and above2. Target Audience: nutrition policy for policymakers, nutrition educators and healthprofessionals3. Created by both the USDA and HHS4. Updated every 5 yearsTwo key concepts of the Dietary Guidelines:Maintain calorie balance over time to achieve and sustain a healthy weightFocus on consuming nutrient-dense foods and beveragesGenerally want to reduce intakes of sodium, saturated fats, and added sugarsIncrease seafood intakeMY Plate – Food PyramidMacronutrient Breakdown of Diet- Total fat 20-35% of kcalo Less than 10% saturated fato Less than 300 mg cholesterol- Carbohydrates 45-65% of kcal- Protein 10-35% of kcalServing: a unit of measurePortion: amount of food actually served or consumedBody Organization:Cells- the basic unit of life- Nucleus is control centerTissue- a group of cells performing a specialized function- Epithelial, Connective, Muscular, NervousOrgan- a group of tissues performing a specialized function- Brain, Heart, LiveThe Digestive SystemDigestion is the breakdown of food components into small enough structures to facilitate absorption- Is both a mechanical and chemical process that takes place at the same time1. The Mouth – chewing (mechanical), saliva (chemical) begins digestion of fat2. The Esophagus- peristaltic movement (mechanical)3. The Stomach- grinding and churning of food (mechanical), pepsin and HCL breakdown proteins into polypeptides (chemical)4. Continues through intestines, colon, liver, and eventually excreted5. Look at sept 17 pptVitamins Vitamins are organic compounds and contain carbonAre needed in small amountsEssential for the body and lack of a vitamin can lead to deficiency syndromesClassification of Vitamins:Fat Soluble- absorbed like dietary fat and they require bile- Vitamins A, D, E, and K- Carried in blood using protein carriers and can be stored in body fat tissues and liverWater Soluble- generally have lower body stores and usually excreted in urine- Thiamin, Riboflavin, Niacin, Pantothenic Acid, Vitamin B6, Folate, Vitamin B12, Biotin and Vitamin C- Low likelihood of toxicityMineralsMinerals are necessary and essential to bodily functionsVitamins and Minerals absorbed best from food (bioavailability)Increased risk of toxicity form high dose supplementsBioavailability- the amount of a nutrient in a food that is actually available for human useVitamin AFunctions: eyesight, cell differentiation and division, gene regulation, bone and teeth growthWhen light falls on the eye, Vitamin A splits from rhodopsin (a pigment within the cells of the retina), which initiates a signal that conveys the sensation of sight to the
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