NUTR 2030: Study Guide for Chapters 1-7 (Science of Nutrition, Macronutrients, Digestion, Carbohydrates, Lipids, Proteins, Alcohol)

Chapter 1: Science of Nutrition

Macronutrients and Nutrients

• Macronutrients are nutrients required in large amounts for energy and body functions. They include carbohydrates, proteins, and lipids (fats).

• Micronutrients are needed in smaller amounts and include vitamins and minerals.

• Water is also an essential nutrient, vital for all bodily processes.

Nutrition-Related Diseases

• Diseases such as obesity, cardiovascular disease, type 2 diabetes, and certain cancers are influenced by nutrition.

Energy Nutrients and Calories per Gram

• Carbohydrates: 4 kcal/g

• Proteins: 4 kcal/g

• Fats (Lipids): 9 kcal/g

• Alcohol (not a nutrient): 7 kcal/g

Influential Factors of Food Choices

• Taste, culture, social trends, cost, convenience, habits, emotions, and health concerns all influence food choices.

Definition of Nutrition

• Nutrition is the science of how food nourishes the body and influences health.

Healthy People 2020

• A set of health objectives for the nation to achieve over a decade, including goals to improve nutrition and reduce chronic diseases.

Essential vs. Nonessential Nutrients

• Essential nutrients must be obtained from the diet because the body cannot make them in sufficient quantities.

• Nonessential nutrients can be synthesized by the body.

Water-Soluble vs. Fat-Soluble Vitamins

• Water-soluble vitamins: B vitamins and vitamin C; not stored in the body, excess excreted in urine.

• Fat-soluble vitamins: Vitamins A, D, E, K; stored in body fat.

Do Vitamins Provide Energy?

• Vitamins do not provide energy (calories) but are essential for energy metabolism.

Anthropometrics and Assessing Dietary Intake

• Anthropometrics: Measurements of body size, weight, and proportions (e.g., BMI, waist circumference).

• Dietary intake can be assessed using food diaries, 24-hour recalls, and food frequency questionnaires.

Obesity and Quality of American Diet

• Obesity rates are high in the U.S., often due to excess calorie intake and low physical activity.

• The typical American diet is often high in added sugars, saturated fats, and sodium, and low in fruits, vegetables, and whole grains.

Functional Foods

• Foods that provide health benefits beyond basic nutrition (e.g., probiotics in yogurt, phytochemicals in fruits).

Chapter 2: Tools for Healthful Eating

Principles of Healthy Eating

• Balance, variety, moderation, and adequacy are key principles.

Tools for Nutrition Recommendations

• Dietary Guidelines for Americans provide science-based advice for healthy eating patterns.

• MyPlate is a visual tool to help plan balanced meals.

Nutrient-Dense Foods

• Foods high in nutrients but relatively low in calories (e.g., vegetables, fruits, lean proteins).

Nutrition Facts Panel

• Provides information on serving size, calories, and nutrient content per serving.

Exchange System

• A meal planning tool that groups foods with similar macronutrient content for diabetes and weight management.

Nutrient Content, Health, and Structure/Function Claims

• Nutrient content claim: Describes the level of a nutrient (e.g., "low fat").

• Health claim: Describes a relationship between a food and reduced risk of a disease.

• Structure/function claim: Describes the effect of a nutrient on normal body structure or function (e.g., "calcium builds strong bones").

Chapter 3: The Human Body & Digestion

Organs of the GI Tract

• Mouth, esophagus, stomach, small intestine, large intestine (colon), rectum, anus.

Accessory Organs

• Liver, pancreas, gallbladder.

Enzymes and Hormones

• Digestive enzymes (e.g., amylase, pepsin, lipase) break down macronutrients.

• Hormones (e.g., gastrin, cholecystokinin/CCK) regulate digestion.

Mechanical vs. Chemical Digestion

• Mechanical digestion: Physical breakdown (chewing, churning).

• Chemical digestion: Enzymatic breakdown of food.

Absorption and Transport

• Nutrients are absorbed mainly in the small intestine.

• Water and some vitamins are absorbed in the colon.

• Nutrients are transported via the cardiovascular and lymphatic systems.

Key Terms

• Pepsin: An enzyme in the stomach that digests proteins.

• Cholecystokinin (CCK): Hormone that stimulates bile release from the gallbladder.

• Lingual lipase: Enzyme in saliva that begins fat digestion.

• Sodium bicarbonate: Secreted by the pancreas to neutralize stomach acid in the small intestine.

Chapter 4: Carbohydrates

Types of Carbohydrates

• Monosaccharides: Single sugar units (glucose, fructose, galactose).

• Disaccharides: Two sugar units (sucrose, lactose, maltose).

Fiber

• Insoluble fiber: Adds bulk to stool, helps prevent constipation.

• Soluble fiber: Lowers blood cholesterol, regulates blood glucose.

Dietary Reference Intake (DRI)

• Guidelines for recommended intake levels of nutrients.

Lactose Intolerance

• Inability to digest lactose due to low lactase enzyme.

Gluconeogenesis

• Formation of glucose from non-carbohydrate sources (e.g., amino acids).

Types of Diabetes

• Type 1: Autoimmune destruction of insulin-producing cells.

• Type 2: Insulin resistance; often related to obesity.

Added Sugar Products

• Foods and beverages with sugars added during processing (e.g., soda, candy).

Key Chemical Reactions

• Hydrolysis: Breaking bonds with water (e.g., digestion of starch).

• Condensation: Forming bonds by removing water (e.g., forming disaccharides).

High Fiber and Whole Grain Food Sources

• Whole grains, legumes, fruits, vegetables.

Ketones and Ketone Bodies

• Produced during fat metabolism when carbohydrate is low.

Diverticulitis and Diverticulosis

• Diverticulosis: Formation of pouches in the colon wall.

• Diverticulitis: Inflammation of these pouches.

Diabetes: Long-Term Consequences and Prevention

• Complications include heart disease, kidney failure, blindness, nerve damage.

• Prevention: Healthy diet, regular physical activity, maintaining healthy weight.

Chapter 5: Lipids

Classification of Fatty Acids

• Saturated fatty acids: No double bonds; solid at room temperature.

• Unsaturated fatty acids: One or more double bonds; liquid at room temperature.

• Polyunsaturated fatty acids (PUFAs): Multiple double bonds (e.g., omega-3, omega-6).

Lipoproteins

• Complexes that transport lipids in the blood (e.g., LDL, HDL, VLDL, chylomicrons).

Essential Fatty Acids

• Must be obtained from the diet (e.g., linoleic acid, alpha-linolenic acid).

Omega Fatty Acids

• Omega-3 (e.g., EPA, DHA) and omega-6 fatty acids are important for heart and brain health.

Stability and Rancidity

• Unsaturated fats are more prone to rancidity (oxidation).

• Prevention: Antioxidants, refrigeration, hydrogenation.

Heart Disease and Lipids

• High intake of saturated and trans fats increases risk of heart disease.

Hydrogenation

• Process that adds hydrogen to unsaturated fats, making them more solid and shelf-stable but creating trans fats.

Triglycerides

• Main form of fat in the diet and body; composed of glycerol and three fatty acids.

Chapter 6: Proteins

Protein Structure and Synthesis

• Building blocks: Amino acids (20 types).

• Peptide bonds: Link amino acids together.

• Protein structures: Primary, secondary, tertiary, quaternary.

• Essential amino acids: Must be obtained from the diet.

Protein Functions

• Enzymes, hormones, transport, immune function, structure, energy (if needed).

• Albumin: Major blood protein for fluid balance.

Protein Digestion and Absorption

• Begins in the stomach (pepsin), continues in the small intestine.

Protein Metabolism

• Involves transcription (DNA to mRNA), translation (mRNA to protein), elongation (adding amino acids).

• Denaturation: Loss of protein structure due to heat, acid, or agitation.

Protein Needs and Calculations

• Recommended Dietary Allowance (RDA): 0.8 g protein/kg body weight for adults.

• Calculation: $\text{Protein~needs~(g)} = \text{Body~weight~(kg)} \times 0.8$

Complete Proteins and Vegetarian Diets

• Complete proteins: Contain all essential amino acids (e.g., animal proteins, soy).

• Vegetarian diets may require combining plant proteins to obtain all essential amino acids.

Protein Deficiency Diseases

• Marasmus: Severe energy and protein deficiency.

• Kwashiorkor: Severe protein deficiency with adequate energy intake.

Protein Quality Assessment

• PDAACS: Protein Digestibility Amino Acid Corrected Score.

• Amino Acid Score: Measures protein quality based on essential amino acid content.

Chapter 7: Alcohol

Standard Drink

• Contains about 14 grams of pure alcohol (e.g., 12 oz beer, 5 oz wine, 1.5 oz spirits).

Short-Term and Long-Term Effects

• Short-term: Impaired judgment, coordination, risk of accidents.

• Long-term: Liver disease, cardiovascular disease, cancer, addiction.

Progression of Alcohol Liver Disease

• Fatty liver → Alcoholic hepatitis → Cirrhosis.

Alcoholism and Alcohol Abuse

• Alcoholism: Chronic disease characterized by uncontrolled drinking and preoccupation with alcohol.

• Alcohol abuse: Pattern of drinking that results in harm to health, relationships, or ability to work.