HN Study Guide PDF: Introduction to Nutrition

Chapter 1: Introduction to Nutrition Factors Influencing Food Choices ​ Taste, culture, social reasons, trends, convenience, emotions, habits, health concerns, advertising, etc. Nutrition Basics ​ Essential Nutrient: A nutrient necessary for body function that must be obtained from...

Chapter 1: Introduction to Nutrition Factors Influencing Food Choices ​ Taste, culture, social reasons, trends, convenience, emotions, habits, health concerns, advertising, etc. Nutrition Basics ​ Essential Nutrient: A nutrient necessary for body function that must be obtained from the diet. Classes of Nutrients Macronutrients (Provide energy in kcals/gram): ​ Carbohydrates: 4 kcal/g ​ Proteins: 4 kcal/g ​ Lipids (Fats): 9 kcal/g Micronutrients (Do not provide energy but are essential for body functions): ​ Vitamins (fat-soluble: A, D, E, K; water-soluble: B-complex, C) ​ Minerals (Major: calcium, potassium, etc.; Trace: iron, zinc, etc.) Calories & Energy Nutrients ​ Calories represent energy provided by macronutrients. Nutrition Professionals ​ Registered Dietitian Nutritionist (RDN) ​ Licensed Nutritionist ​ Healthcare providers with nutrition expertise Evaluating Nutrition Information ​ Look for peer-reviewed research, credible sources, and expert opinions. Chapter 2: Nutritional Assessment & Guidelines ABCDs of Nutritional Assessment  1.​ Anthropometric - Measurements of body size and composition (e.g., BMI, waist circumference). 2.​ Biochemical - Lab tests for blood, urine, or tissue samples. 3.​ Clinical - Observations of physical symptoms (e.g., hair loss, skin health). 4.​ Dietary - Food intake history, diet records, and food frequency questionnaires. Dietary Reference Intakes (DRIs) ​ EAR (Estimated Average Requirement) - Average daily nutrient intake estimated to meet the needs of 50% of individuals. ​ RDA (Recommended Dietary Allowance) - Average intake level sufficient for nearly all healthy individuals. ​ AI (Adequate Intake) - Used when RDA cannot be determined. ​ TUL (Tolerable Upper Limit) - Maximum daily intake unlikely to cause adverse effects. Acceptable Macronutrient Distribution Ranges (AMDRs) ​ Carbohydrates: 45-65% of daily calories ​ Lipids: 20-35% of daily calories ​ Proteins: 10-35% of daily calories Dietary Guidelines for Americans (2020) ​ Focus on variety, nutrient density, and portion control. ​ Limit added sugars, saturated fats, and sodium. ​ Increase fruit, vegetable, whole grain, and lean protein intake. Choose MyPlate/Daily Food Plan ​ Emphasizes balance, variety, moderation, and nutrient density. Food Labels ​ Basic Label Format: Nutrition Facts panel, ingredients list, serving size. ​ Daily Values (DV): Helps compare nutrient content of foods. ​ Health Claims vs. Structure-Function Claims: ○​ Health claims require FDA approval (e.g., "lowers cholesterol"). ○​ Structure-function claims do not (e.g., "supports immune health"). ​ Whole Grains: Must contain the entire grain kernel. ​ Fortified & Enriched Foods: ○​ Fortified: Nutrients added that weren’t originally present. ○​ Enriched: Nutrients added back after processing. ​ Organic Labeling: Must meet USDA organic standards. ​ Weight Stigma & Nutrition: Stigma can negatively impact healthcare and nutrition choices. ​ BMI (Body Mass Index): Screening tool for weight-related health risks. Chapter 3: Digestion & Metabolism Digestive Tract & Major Organs ​ Order of Digestion: Mouth → Esophagus → Stomach → Small Intestine → Large Intestine → Rectum Key Definitions ​ Bolus: Chewed food mixed with saliva. ​ Chyme: Semi-liquid food mixture in the stomach. ​ Peristalsis: Wave-like muscle contractions moving food through the GI tract. Phases of Digestion 1.​ Cephalic Phase: Brain signals digestive system when food is seen/smelled. 2.​ Gastric Phase: Stomach releases digestive juices and enzymes. 3.​ Intestinal Phase: Nutrient absorption in small intestine. Role of Digestive Organs ​ Salivary Glands: Produce saliva, begin carbohydrate digestion. ​ Esophagus: Moves food via peristalsis. ​ Stomach: Breaks down food with acid and enzymes. ​ Small Intestine: Main site of digestion and absorption. ​ Large Intestine: Absorbs water and forms waste. ​ Pancreas: Produces digestive enzymes and insulin. ​ Liver: Produces bile for fat digestion. ​ Gallbladder: Stores and releases bile. Nutrient Transport ​ Blood Transport: Water-soluble nutrients (carbohydrates, proteins, B vitamins, vitamin C) enter bloodstream. ​ Lymphatic Transport: Fat-soluble nutrients (lipids, vitamins A, D, E, K) enter the lymphatic system. Gut Health & Microbiome ​ Prebiotics: Non-digestible fibers that feed beneficial bacteria (e.g., garlic, onions, bananas). ​ Probiotics: Live beneficial bacteria (e.g., yogurt, kefir, sauerkraut). GI Disorders  ​ Dysphagia: Difficulty swallowing. ​ GERD (Gastroesophageal Reflux Disease): Acid reflux causing heartburn. ​ Peptic Ulcer: Sores in the stomach lining. ​ Celiac Disease: Autoimmune reaction to gluten damaging the small intestine. Chapters 4 & 11: Carbohydrates Types of Carbohydrates ​ Simple CHO: ○​ Monosaccharides: Glucose, fructose, galactose ○​ Disaccharides: Sucrose, lactose, maltose ​ Complex CHO: ○​ Oligosaccharides ○​ Polysaccharides: Starch, glycogen, fiber Dietary Fiber ​ Health benefits: Digestion, heart health, blood sugar control ​ Sources: Whole grains, fruits, vegetables, legumes Added Sugars ​ Sources: Sodas, candy, baked goods ​ Concerns: Obesity, diabetes, dental issues Blood Glucose Regulation ​ Insulin: Lowers blood sugar ​ Glucagon: Raises blood sugar Types of Diabetes ​ Type 1: Autoimmune, insulin-dependent ​ Type 2: Insulin resistance, lifestyle-related ​ Gestational: During pregnancy, risk of Type 2 later Chapter 5 & 11: Lipids Functions & Types ​ Triglycerides: Composed of glycerol and three fatty acids, used for energy storage.  ○​ Saturated Fatty Acids: Found in animal products and some plant oils; solid at room temperature. ○​ Monounsaturated Fatty Acids: Found in olive oil, avocado, nuts; liquid at room temperature. ○​ Polyunsaturated Fatty Acids: Found in fish, flaxseeds, walnuts; includes essential fatty acids. ○​ Essential Fatty Acids: ​ Omega-3 (Linolenic Acid): Supports heart and brain health; found in fatty fish, flaxseeds. ​ Omega-6 (Linoleic Acid): Supports growth and inflammation control; found in vegetable oils. ​ Phospholipids: Major components of cell membranes, help emulsify fats. ​ Sterols (Cholesterol): Essential for hormone production, cell membranes, and bile synthesis. ○​ Found in animal-based foods like eggs, dairy, and meat. Heart Health & Lipoproteins ​ Lipoproteins transport lipids in the blood: ○​ HDL (High-Density Lipoprotein): "Good cholesterol," helps remove excess cholesterol. ○​ LDL (Low-Density Lipoprotein): "Bad cholesterol," high levels increase heart disease risk. ​ Cardiovascular Health & Risk Factors: ○​ High intake of trans fats and saturated fats increases LDL levels. ○​ A diet rich in unsaturated fats, fiber, and plant foods supports heart health. ○​ The Mediterranean Diet emphasizes healthy fats, whole grains, and lean proteins to reduce heart disease risk. Functions & Types ​ Triglycerides: Energy storage ​ Phospholipids: Cell membranes ​ Sterols (Cholesterol): Hormone synthesis Heart Health & Lipoproteins ​ HDL: "Good cholesterol" ​ LDL: "Bad cholesterol" ​ Mediterranean Diet: Healthy fat balance Chapter 6: Proteins Amino Acids & Protein Structure ​ Amino Acids: Building blocks of proteins. ○​ Essential Amino Acids: Must be obtained from the diet. ○​ Non-Essential Amino Acids: Can be synthesized by the body. ○​ Conditionally Essential Amino Acids: Required under specific conditions (e.g., illness, stress). ​ Protein Structure: ○​ Composed of amino acids linked by peptide bonds. ○​ Denaturation: Process where protein structure is altered due to heat, acid, or mechanical action. Protein Functions ​ Enzyme and hormone production. ​ Tissue growth, repair, and maintenance. ​ Fluid balance, immune function, and energy source when needed. Protein Metabolism & Nitrogen Balance ​ Protein Turnover: Continuous breakdown and synthesis of proteins in the body. ​ Nitrogen Balance: ○​ Positive Balance: Needed for growth, pregnancy, and muscle building. ○​ Negative Balance: Occurs during illness, malnutrition, and muscle wasting. Protein Quality & Dietary Sources ​ Complete Proteins: Contain all essential amino acids (e.g., animal products, soy). ​ Incomplete Proteins: Missing one or more essential amino acids (e.g., plant-based proteins). ​ Protein Complementation: Combining different plant-based protein sources (e.g., rice and beans). Vegetarian Diets & Protein Considerations ​ Types of Vegetarian Diets: Lacto-ovo, vegan, pescatarian, etc. ​ Health Benefits: Reduced risk of chronic diseases, lower environmental impact. Protein Energy Malnutrition (PEM) ​ Kwashiorkor: Severe protein deficiency, leading to edema and muscle wasting. ​ Marasmus: Severe calorie and protein deficiency, resulting in extreme weight loss and weakness. ​ Amino Acids: Essential vs. non-essential ​ Protein Quality: Complete vs. incomplete proteins ​ Vegetarian Diets: Protein complementation ​ Malnutrition: Kwashiorkor, Marasmus