1.1 What is Nutrition

Chapter 1: What Drives Our Food Choices?

Importance of Nutrients

• We depend on food to obtain essential nutrients necessary for:

  • Energy: Fuel for bodily functions and growth.

  • Maintenance: Supports ongoing bodily functions.

  • Regulation: Controls processes in the body.

Six Classes of Nutrients

• Carbohydrates: Primary source of energy.

• Lipids: Provide essential fatty acids and energy.

• Proteins: Build and repair tissues.

• Vitamins: Support biochemical functions.

• Minerals: Essential for various body functions.

• Water: Vital for life, involved in many processes.

Non-Nutrient Compounds

• Food also contains non-nutrient compounds that:

  • Contribute to overall health.

  • May assist in fighting chronic diseases.

Factors Influencing Food Choices

• Beyond nutrition, we choose foods for a variety of reasons:

  • Taste: Preference for flavors.

  • Cost & Convenience: Economic factors and ease of access.

  • Traditions & Habits: Cultural influences on food practices.

  • Ethnicity & Culture: Foods often linked to cultural identity.

  • Social Trends: Popular dietary patterns and movements.

  • Stress: Emotional states can influence eating behaviors.

  • Advertisement: Marketing and promotions encourage certain choices.

Nutrition Defined

• Nutrition: The science that studies how food nutrients affect body functions and health.

• Chronic deficiencies or excesses in nutrient intake can impact health.

• Good nutrition lowers the risk of many chronic conditions.

Leading Causes of Death in the United States

• Major health issues include:

  • Heart Disease

  • Cancer

  • Respiratory Diseases

  • Accidents

  • Stroke

  • Alzheimer's Disease

  • Diabetes

  • Influenza/Pneumonia

  • Kidney Disease

  • Intentional Self-Harm

Nutrient Groups

• Macronutrients: Need large amounts to maintain bodily functions.

• Micronutrients: Needed in smaller amounts but still vital.

• Water: Essential for all physiological processes.

Macronutrients: Energy and Composition

• Macronutrients provide the energy required for metabolism:

  • Carbohydrates: 4 kcal/g

  • Lipids: 9 kcal/g

  • Proteins: 4 kcal/g

• Composition:

  • Carbohydrates: Consist of carbon, hydrogen, and oxygen.

  • Lipids: Contain carbon, hydrogen, and oxygen, with fatty acids.

  • Proteins: Composed of carbon, hydrogen, oxygen, and nitrogen.

• Energy Measurement:

  • Measured in Joules, kilocalories (kcal), or dietary calories (Cal).

  • 1 kcal = energy needed to raise 1 kg of water by 1 °C.

Essential Nutrients and Their Energy Values

• To calculate the energy provided by food:

  • Carbohydrates provide 4 kcal/g.

  • Proteins provide 4 kcal/g.

  • Fat provides 9 kcal/g.

Examples of Caloric Calculations

• Minute Maid Apple Juice: 27.5g of carbohydrates

• Egg white: 4g of protein

• Butter: 12g of fat

• Orange: Specific calorigenic value calculation based on content.

Micronutrients: Roles and Functions

• Vitamins: Organic compounds necessary to be obtained from food; assist enzymes in speeding up reactions in the body.

• Minerals: Inorganic substances key to body processes and structure.

The Role of Water in the Body

• Water is crucial for numerous body processes:

  • Acts as a fluid medium inside and outside cells.

  • Participates in chemical reactions, including energy production.

  • Maintains body temperature and facilitates nutrient transport.

  • Acts as a lubricant for joints, eyes, mouth, and intestines.

  • Provides protection for organs as a cushion.