Chapter 1 Overview: An Overview of Nutrition

Overview of Nutrition

  • NTR 306 course content: Fundamentals of Nutrition, Chapter 1 – An Overview of Nutrition.

  • Course tools mentioned: InstaPolls, Chats, Discussion Board, and a Handy Resource Module. Do not email TAs/instructors about Instapolls; check if answers were recorded and review course requirements. If problems persist, contact your TA.

  • Interactive activity: InstaPoll prompt – when you think of nutrition, what is one word that comes to mind?

  • Real-life prompt: “What’s in Your Fridge?” as a practical reflection activity.

Key Concepts: What is Nutrition?

  • Nutrition is the branch of science examining the nutrients in foods and their actions within the body to impact health and well-being across all life stages.

  • Nutrients are substances that are essential for growth, development, and maintenance of life.

  • Foods are substances that people eat or drink to yield energy and/or nutrients for growth, development, and maintenance of life. This includes both solid foods and beverages.

Dietary Patterns and Health

  • Dietary Pattern defined:

    • The combination of foods and beverages habitually consumed within eating occasions across each day (over days/weeks/months).

    • NOT the same as a dieting or weight-loss diet.

    • Highly individualized and liked (enjoyed).

    • Includes life-sustaining nutrients and energy plus components to limit.

  • Patterns that promote health are linked to:

    • Longevity (life expectancy)

    • Chronic disease prevention

    • Quality of life

Influences on Food Choices within Dietary Patterns

  • Biological factors: Taste.

  • Economic factors: Cost, income, availability.

  • Physical factors: Cooking skills, time.

  • Social factors: Family/peers, meal patterns.

  • Psychological factors: Mood, stress, guilt, goals.

  • Information factors: Attitudes/beliefs, marketing, nutrition knowledge/health.

Nutrients: An Overview

  • Nutrients are chemical substances in foods that provide energy, structural materials, and regulating agents.

  • They support growth, tissue maintenance and repair, and reduce disease risks.

  • Classification by carbon content:

    • Inorganic nutrients: do not contain carbon (examples: minerals and water).

    • Organic nutrients: contain carbon (examples: carbohydrates, lipids, proteins, vitamins).

  • Major concepts:

    • The body contains: Water ~60%; Fat ~18–21% (men) or ~23–26% (women); remaining is other nutrients.

    • Organic nutrients: carbohydrates, lipids (fats), proteins, vitamins.

    • Inorganic nutrients: minerals and water.

    • Alcohol is not a nutrient and can interfere with growth, regulation, and repair of the body.

Six Classes of Nutrients (Table Concept)

  • Carbohydrates — Organic, Energy-yielding, Macronutrient.

  • Lipids (fats) — Organic, Energy-yielding, Macronutrient.

  • Proteins — Organic, Energy-yielding, Macronutrient.

  • Vitamins — Organic, Not energy-yielding, Micronutrient.

  • Minerals — Inorganic, Not energy-yielding, Micronutrient.

  • Water — Inorganic, Not energy-yielding, Essential nutrient.

Macronutrients vs Micronutrients

  • Macronutrients: required in relatively large amounts; energy-yielding (calories).

    • Carbohydrates, lipids, and proteins.

  • Micronutrients: required in small amounts; do not provide calories.

    • Vitamins and minerals.

  • Alcohol is not a nutrient.

Carbohydrates

  • Role:

    • Primary source of short-term energy for the body, especially for brain function and physical activity.

    • Used to build other molecules and structures in the cell.

  • Common names: CHOs or carbs.

  • Common foods: breads, pasta, vegetables, fruits, legumes, seeds, nuts, sweets, milk products.

Lipids (Fats)

  • Role:

    • Major form of stored energy (adipose tissue).

    • Energy source during rest or low- to moderate-intensity exercise.

    • Used to make cell membranes and other complex molecules.

  • Common foods: oils, animal fats, seeds, nuts.

Proteins

  • Role:

    • ~50% of cellular content; perform most cellular work.

    • Required for structure, function, and regulation of organs, tissues, and body systems.

    • Support tissue growth, repair, and maintenance.

  • Common foods: meat, dairy, seeds, nuts, legumes; small amounts in vegetables and whole grains.

Vitamins

  • Do not supply energy to the body.

  • Micronutrients (required in smaller amounts).

  • 13 vitamins regulate many body processes.

  • Organic molecules (contain carbon).

  • Can be destroyed by heat, light, and chemical agents.

Minerals

  • Do not supply energy to the body.

  • 16 minerals essential for several body processes.

  • Inorganic substances (do not contain carbon).

  • Major minerals vs trace minerals distinctions exist in practice.

  • Indestructible: not vulnerable to heat, light, or chemical agents (in many cases).

Water

  • Essential nutrient.

  • Inorganic (does not contain carbon).

  • Involved in nearly all body processes.

How Do We Use Nutrients? Priority Framework

  • Priority #1: Using nutrients for energy.

    • When bonds between nutrient atoms break, energy is released.

    • Energy can be used immediately, stored short-term (between meals or overnight), or stored long-term as body fat for later use.

  • Other key priorities:

    • Provide building blocks and materials for body tissues.

    • Regulate bodily activities: digestion, energy metabolism, organ system function.

Energy from Nutrients (Calories)

  • Energy from food is measured in kilocalories (kcal).

  • Calorie content depends on macronutrient type:

    • Carbohydrates: 4 \, \text{kcal/g}

    • Protein: 4 \, \text{kcal/g}

    • Lipids (fats): 9 \, \text{kcal/g}

  • Vitamins, minerals, and water do not provide calories.

  • Most foods are a mixture of nutrients; exceptions include pure sugar (100% CHO) and pure oil (100% FAT).

Nutrient Calculations: A Practical Example

  • Example: A burrito contains: FAT = 12 g, CHO = 55 g, PRO = 15 g; Total kcal = 388 kcal.

  • Calculations:

    • Fat energy: FAT_kcal = 12 \ \text{g} \times 9 \ \text{kcal/g} = 108 \ \text{kcal}

    • Carbohydrate energy: CHO_kcal = 55 \ \text{g} \times 4 \ \text{kcal/g} = 220 \ \text{kcal}

    • Protein energy: PRO_kcal = 15 \ \text{g} \times 4 \ \text{kcal/g} = 60 \ \text{kcal}

    • Total energy: 108 + 220 + 60 = 388 \ \text{kcal}

Macronutrient Distribution (Percent of Total kcal)

  • Fat percentage:

    • \text{Fat \%} = \frac{108}{388} \times 100 \% \approx 28\%

  • Carbohydrate percentage:

    • \text{CHO \%} = \frac{220}{388} \times 100 \% \approx 57\%

  • Protein percentage:

    • \text{PRO \%} = \frac{60}{388} \times 100 \% \approx 15\%

Practice Example: Ice Cream Nutrition Calculation

  • Serving size: 1 serving (2/3 cup) with: FAT = 21 g, CHO = 37 g, PRO = 6 g; Total kcal = 361 kcal.

  • Calculations:

    • Fat energy: FAT_kcal = 21 \ \text{g} \times 9 \ \text{kcal/g} = 189 \ \text{kcal}

    • Carbohydrate energy: CHO_kcal = 37 \ \text{g} \times 4 \ \text{kcal/g} = 148 \ \text{kcal}

    • Protein energy: PRO_kcal = 6 \ \text{g} \times 4 \ \text{kcal/g} = 24 \ \text{kcal}

    • Total energy: 189 + 148 + 24 = 361 \ \text{kcal}

  • Distribution:

    • Fat %: \frac{189}{361} \approx 0.523 \Rightarrow 52\%

    • CHO %: \frac{148}{361} \approx 0.410 \Rightarrow 41\%

    • PRO %: \frac{24}{361} \approx 0.066 \Rightarrow 6.6\%

  • Entire container calculation (if 3 servings per container):

    • Total kcal: 3 \times 361 = 1083 \text{ kcal}

Bomb Calorimeter vs Real-Life Energy Availability

  • Bomb calorimeter

    • Direct measurement: food burns → releases heat energy (food’s kcal value).

    • Not exact: the human body is not 100% efficient at converting food energy into usable energy.

  • Implication: kcal values from kitchen/bomb calorimeters are approximate representations of actual energy available to the body.

Quick Check: Class Polls and Interactive Review

  • InstaPoll and class polls gauge understanding and opinions on nutrition concepts.

  • “How’d we do?” scale (1–10) for nutrition math appetite and comfort levels helps tailor instruction.

Wrap-up and Reminders

  • Next live class: Tuesday, 9/2.

  • Chapter to cover: Chapter 2, Planning a Healthy Diet.

  • Brief discussion about Dietary Analysis Project.

  • Post any questions from today’s class on the Discussion Board for today’s lecture.

  • CFU #1 (Syllabus & Course Introduction) due: Monday, 9/1 by 11:59 pm (holiday—get it done early).