Unit 2: Nutrition and Health

• NUTRITION; the science of how the body uses food
• NUTRITIOUS


  The extent to which food provides nutrients for health
• NUTRIENTS


  Substances found in food and needed by the body to function, grow, repair itself, and produce energy
• Nutrients provide


  • Fuel for cell activity
  • The physical and metabolic basis for nearly all we are and all we do
• ESSENTIAL NUTRIENT


  Those that the body cannot make itself but are needed to build and maintain body tissue (ie, calcium, vitamin C, protein, etc.)
• BALANCE

  • Macro & micro nutrients
• VARIETY

  • Foods, colours, nutrients
• MODERATION

  • We can eat all types of foods, just not too much
• Energy-producing nutrients

  • Carbohydrates
  • Fats
  • Proteins
• Nutrients that do NOT provide energy (calories)

  • Water
  • Vitamins
  • Minerals
• Nutrients that do NOT provide calories

  • Fibre
  • Cholesterol
• Energy-Yielding Nutrients


  Nutrients that break down to yield energy the body can use
• Macronutrients


  Also called energy-yielding nutrients
• Carbohydrates

  4 kcal/g
• Fat

  9 kcal/g
• Protein

  4 kcal/g
• Recommended Energy Distribution (14-18 years)

  • Fats: 25-35%
  • Carbohydrates: 45-65%
  • Proteins: 10-30%
• Alcohol

  Provides 7 calories per gram consumed, but is not considered a nutrient as it does not promote growth, maintain cells, or repair tissues
• Calorie


  A unit that measures how much energy a particular food provides to the body
• Calories are energy, we need them to live
• Calories come from carbohydrates, proteins, fat (and alcohol)
• Not all calories are created equal, different calories from food fill us up differently, and are used differently by the body
• There is no need to count calories, try to listen to your body - it knows what it needs
• Nutrient-dense foods


  The opposite of empty-calorie foods, they pack a solid nutrition punch by providing a good amount of vitamins, minerals, and/or fibre in comparison to the number of calories they provide
• Basal Metabolic Rate (BMR)


  The measure of the rate at which a person's body "burns" energy, in the form of calories, while at rest
• BMR is sufficient only for the functioning of the vital organs, the heart, lungs, nervous system, kidneys, liver, intestine, sex organs, muscles, and skin
• Factors Affecting Caloric Needs (BMR)

  • Genetics
  • Gender
  • Age
  • Body Fat Percentage
  • Diet
  • Body Temperature
  • External Temperature
  • Exercise
• Teens are not getting enough calcium, iron, fibre, and water
• Metabolism


  A collection of chemical reactions in the body's cells that convert the fuel from food into the energy needed to power everything we do from moving to thinking to growing
• Metabolic Rate

  • How fast the chemical processes of metabolism take place
• Metabolism

  1. Building up of body tissues and energy stores

  2. Breaking down of body tissues and energy stores to generate more fuel for body functions
• A calorie is a unit that measures how much energy a particular food provides to the body
• Photosynthesis

  1. Plant takes in energy from sunlight

  2. Plant uses energy and chlorophyll to build sugars from water and carbon dioxide
• Metabolism in humans

  1. People and animals eat plants (or animals that have eaten plants)

  2. Body breaks down sugar to release energy

  3. Energy distributed to and used as fuel by body cells
• Digestion

  1. Enzymes break down proteins into amino acids

  2. Enzymes break down fats into fatty acids

  3. Enzymes break down carbohydrates into simple sugars
• Metabolism in cells

  1. Enzymes speed up or regulate chemical reactions

  2. Energy from compounds released for use by body or stored in tissues
• Anabolism


  Building and storing - supports growth of new cells, maintenance of body tissues, and storage of energy
• Catabolism

  Producing energy required for all activity in cells - breaking down large molecules to release energy
• After eating a meal

  More anabolic activity occurs as insulin signals cells to increase anabolic activities
• Whole food

  Food with only one ingredient