Comprehensive Nutrition Study Guide for Final Exam

Estimated Average Requirements (EARs)

Nutrient intake values estimated to meet the needs of 50% of healthy individuals in a particular life stage and gender group.

Recommended Dietary Allowances (RDAs)

Nutrient intake levels sufficient to meet the needs of 97-98% of healthy individuals in a particular life stage and gender group.

Adequate Intakes (AIs)

Nutrient intake levels assumed to be adequate when an RDA cannot be established due to a lack of sufficient data.

Tolerable Upper Intake Levels (ULs)

The maximum daily intake levels that are unlikely to cause harmful effects in almost all individuals in a particular life stage and gender group.

Acceptable Macronutrient Distribution Ranges (AMDRs)

Recommended ranges for the intake of carbohydrates, fats, and proteins as a percentage of total daily calories.

Purpose of Healthy People 2030

Healthy People 2030 is a U.S. government initiative that sets national objectives to improve the health of Americans over the next decade.

Characteristics of Eating Patterns Associated with Positive Health Outcomes

High in fruits, vegetables, whole grains, and lean proteins; emphasizes plant-based foods and includes moderate amounts of healthy fats; low in processed foods, refined sugars, and red meats.

Characteristics of Eating Patterns Associated with Detrimental Health Outcomes

High in processed foods, added sugars, refined grains, and unhealthy fats; low in fruits, vegetables, and whole grains; high in sodium and low in fiber.

Diet Quality in the United States

The overall diet quality in the U.S. is suboptimal, with many people consuming diets that are high in calories but low in essential nutrients.

Four Modifiable Lifestyle Risk Factors for Chronic Disease

Poor diet, physical inactivity, tobacco use, and excessive alcohol consumption.

Characteristics of Lifestyle Medicine

Focuses on preventing, treating, and even reversing chronic diseases through lifestyle changes; emphasizes patient empowerment and long-term health improvements.

Potential Future Benefits of Nutrigenomics

Nutrigenomics is the study of how individual genetic variations affect responses to nutrients and dietary patterns, potentially leading to personalized nutrition plans.

Four Broad Dietary Guidelines

Follow a healthy eating pattern across the lifespan; emphasize a variety of nutrient-dense foods from all food groups.

Nutrient-Dense Foods

Foods that provide a high amount of vitamins, minerals, and other nutrients relative to their calorie content.

Limit added sugars, saturated fats, and sodium

Reduce intake of processed foods, sugary drinks, and high-fat meats. Aim for less than 10% of calories from added sugars and saturated fats.

Healthy U.S.-Style Eating Pattern

Emphasizes whole foods, such as fruits, vegetables, whole grains, lean proteins (like fish and legumes), and low-fat dairy. Limits added sugars, sodium, and saturated fats.

Typical American Eating Pattern

High in processed foods, red meats, sugar-sweetened beverages, and refined grains. Low in fruits, vegetables, and whole grains.

Variety

Eating a wide range of foods from different food groups.

Balance

Ensuring an appropriate intake of macronutrients (carbs, proteins, fats) and micronutrients.

Moderation

Avoiding excess calories and harmful substances like added sugars and unhealthy fats.

Nutrient Density

Choosing foods that provide a high amount of nutrients for the fewest calories.

Examples of Nutrient-Dense Foods

Leafy greens (e.g., spinach, kale), Berries (e.g., blueberries, strawberries), Whole grains (e.g., quinoa, brown rice), Lean protein sources (e.g., chicken, fish, beans), Nuts and seeds (e.g., almonds, chia seeds).

MyPlate

A visual guide to healthy eating that divides a plate into sections representing the five food groups: fruits, vegetables, grains, protein, and dairy. It encourages portion control and a balanced intake of these groups.

Fruits

Rich in vitamins, minerals, and fiber; help reduce the risk of chronic diseases like heart disease and cancer.

Vegetables

High in fiber, vitamins, and antioxidants; support digestive health and may help prevent certain cancers.

Grains

Whole grains provide fiber, B vitamins, and minerals like iron and magnesium. They support energy levels and digestive health.

Protein

Sources include meat, poultry, seafood, beans, nuts, and seeds. They are essential for muscle repair and growth and maintaining immune health.

Dairy

Provides calcium, vitamin D, and protein for bone health and maintaining strong muscles.

American Heart Association (AHA)

Focuses on reducing saturated fats, trans fats, cholesterol, and sodium. Encourages the consumption of fruits, vegetables, whole grains, and healthy fats (e.g., from fish, nuts).

American Cancer Society (ACS)

Recommends a plant-based diet with a focus on fruits, vegetables, whole grains, and legumes. Recommends limiting red and processed meats, alcohol, and sugar intake.

American Institute for Cancer Research (AICR)

Advocates for a diet rich in plant foods, focusing on whole grains, fruits, and vegetables. Recommends limiting red and processed meats, sugary drinks, and alcohol.

Classification of Carbohydrates

Carbohydrates are classified based on their structure and complexity: Monosaccharides: Simple sugars (e.g., glucose, fructose, galactose), Disaccharides: Two monosaccharides linked (e.g., sucrose, lactose, maltose), Polysaccharides: Complex carbohydrates (e.g., starch, glycogen, fiber).

Sources of Carbohydrates

Natural sources: Fruits, vegetables, dairy, whole grains, legumes; Refined sources: White bread, pasta, pastries, sugary drinks; Added sugars: Found in processed foods like candies and sodas.

Glycemic Index (GI)

Measures how quickly carbohydrates raise blood glucose.

Glycemic Load (GL)

Considers both GI and the amount of carbohydrates per serving.

Usefulness of Glycemic Load

Helps in managing blood sugar, particularly for diabetics.

Criticism of Glycemic Load

Individual responses to food vary, and other nutrients affect glucose absorption.

Primary Energy Source

Essential for brain function and physical activity

Spares Protein

Prevents the body from using protein for energy

Aids Digestion

Fiber promotes gut health and regularity

Stored Energy

Glycogen in liver and muscles serves as a backup fuel source

Increasing Dietary Fiber

Replace refined grains with whole grains: Brown rice, whole wheat bread

Increasing Dietary Fiber

Incorporate more legumes: Lentils, beans

Increasing Dietary Fiber

Increase fruit and vegetable intake: Apples, carrots, leafy greens

Increasing Dietary Fiber

Choose high-fiber snacks: Nuts, seeds, and popcorn

Carbohydrate Intake Recommendations

Dietary Guidelines for Americans (DGA) suggest: 45-65% of daily calories from carbohydrates

Carbohydrate Intake Recommendations

Limit added sugars to <10% of daily calories

Carbohydrate Intake Recommendations

Consume at least 25-30 grams of fiber per day

Increasing Whole Grain Intake

Choose whole grain options: Whole wheat, quinoa, barley

Increasing Whole Grain Intake

Read labels for '100% whole grain'

Increasing Whole Grain Intake

Swap white rice for brown rice or quinoa

Increasing Whole Grain Intake

Try whole grain pasta instead of refined pasta

Sugar Alternatives: Pros and Cons

Benefits: Low-calorie, beneficial for diabetics, reduce risk of cavities

Sugar Alternatives: Pros and Cons

Disadvantages: May cause digestive issues, potential for increased cravings

Sugar Alternatives: Pros and Cons

Examples: Stevia, aspartame, sucralose, monk fruit extract

Essential Amino Acids

Must be obtained from diet (e.g., leucine, lysine)

Nonessential Amino Acids

Can be synthesized by the body (e.g., alanine, glutamine)

Functions of Protein

Essential for muscle, skin, and organ tissue repair

Functions of Protein

Helps in metabolism and bodily functions

Functions of Protein

Produces antibodies

Functions of Protein

Carries oxygen (hemoglobin) and stores nutrients

Functions of Protein

Prevents swelling (edema)

Positive Nitrogen Balance Conditions

Occurs when protein intake exceeds breakdown: Growth periods, pregnancy and lactation, recovery from illness or injury, strength training and muscle building

Complete Proteins

Contain all essential amino acids (e.g., meat, fish, dairy, eggs, quinoa, soy)

Incomplete Proteins

Missing one or more essential amino acids (e.g., beans, nuts, grains)

Calculating Protein Requirements

Recommended intake: 0.8 g/kg of body weight for healthy adults

Calculating Protein Requirements

Athletes and special conditions may require 1.2-2.0 g/kg

Calculating Protein Requirements

Example: A 70 kg person needs 56 g of protein daily

Improving Protein Food Choices

Choose lean proteins: Skinless poultry, fish, tofu

Improving Protein Food Choices

Incorporate plant-based proteins: Lentils, chickpeas, nuts

Improving Protein Food Choices

Reduce processed meats: Avoid sausages, hot dogs, and bacon

Improving Protein Food Choices

Balance protein intake throughout the day

Conditions That Increase Protein Needs

Illness and injury recovery

Conditions That Increase Protein Needs

Pregnancy and breastfeeding

Conditions That Increase Protein Needs

Elderly individuals (to prevent muscle loss)

Conditions That Increase Protein Needs

Athletes and bodybuilders

Sources of Lean Protein

Animal-based: Chicken, turkey, fish, low-fat dairy

Sources of Lean Protein

Plant-based: Legumes, tofu, tempeh, quinoa

Nutrients Often Deficient in Vegetarian Diets

Vitamin B12 (found in animal products; supplementation needed)

Nutrients Often Deficient in Vegetarian Diets

Iron (plant sources: spinach, lentils; best absorbed with vitamin C)

Nutrients Often Deficient in Vegetarian Diets

Zinc (nuts, whole grains, dairy)

Nutrients Often Deficient in Vegetarian Diets

Omega-3 fatty acids (flaxseeds, walnuts, algae-based supplements)

Nitrogen Balance

Measures protein intake vs. loss

Positive Nitrogen Balance

Growth, pregnancy, muscle gain

Negative Nitrogen Balance

Malnutrition, severe illness, muscle loss

Determined by Nitrogen Balance

Measuring nitrogen in diet and excretion (urine, feces, sweat)

Saturated fatty acids

Found in animal products (butter, cheese, fatty meats) and tropical oils (coconut oil). Excess consumption can raise LDL cholesterol and increase heart disease risk.

Monounsaturated fatty acids

Found in olive oil, avocados, nuts, and seeds. Helps reduce LDL cholesterol while maintaining HDL levels.

Polyunsaturated fatty acids

Found in fatty fish, walnuts, flaxseeds, and sunflower oil. Essential for brain function and reducing inflammation.

Dietary Cholesterol

Found in animal-based foods such as egg yolks, dairy products, meat, and seafood.

Synthetic Trans Fats

Created through hydrogenation of vegetable oils. Found in margarine, processed snacks, fried foods, and commercial baked goods.

Functions of Fat in the Body

Energy storage, insulation, cell membrane structure, vitamin absorption (A, D, E, K), hormone production.

Digestion and Absorption of Fat

Begins in the small intestine with bile acids and pancreatic lipase breaking down fat into fatty acids and glycerol, which are absorbed into the lymphatic system.

Omega-3 Fatty Acids

Foods providing omega-3 fatty acids include fatty fish (salmon, mackerel, sardines), chia seeds, flaxseeds, and walnuts.

Healthier Food Choices Based on Fat

Choose healthy fats (olive oil, nuts) over saturated/trans fats. Limit processed and fried foods. Opt for lean meats and fish.

Fat-Soluble Vitamins

Stored in fat tissues; excess intake can be toxic.

Water-Soluble Vitamins

Easily excreted in urine; must be consumed regularly.

General Functions of Vitamins

Support metabolism, immunity, growth, and development.

When Vitamin Supplements May Be Necessary

Deficiencies, pregnancy, vegan diets, certain medical conditions.

Food Sources for Individual Vitamins

Vitamin A: Carrots, sweet potatoes. Vitamin C: Citrus fruits. Vitamin D: Sunlight, fortified dairy. B vitamins: Whole grains, beans.