Nutrition

Carbohydrates

• Types: Simple (Sugars), Complex (Starches & Fibre)

• Function: Primary energy source

• Food Sources: Simple - Fruits; Complex - Oats

• Absorption: Broken down into Glucose

Proteins

• Types: Complete (All 9 amino acids), Incomplete (Missing 1 or more amino acids)

• Function: Tissue repair and growth

• Food Sources: Complete - Lean Meat; Incomplete - Legumes

• Absorption: Broken down into Amino Acids

Fats

• Types: Cholesterol, Trans, Saturated, Monounsaturated, Polyunsaturated

• Function: Absorb fat-soluble vitamins

• Food Sources: Cholesterol - Animal food origin; Trans - Baked goods (cookies); Saturated - Animals & oils (palm oil); Monounsaturated - Nuts; Polyunsaturated - Vegetable oils

• Absorption: Broken down into Fatty Acids & Glycerol

Water

• Functions: Keeps the body hydrated, regulates body temperature

• Sources: Drinking water, Watermelon

Fat Soluble Vitamins

• Vitamin A: Function - Eye sight, healthy skin; Source - Carrots; Deficiency - Night blindness, impaired bone growth, impaired immunity

• Vitamin D: Function - Calcium absorption; Source - Fish & eggs

• Vitamin E: Function - Antioxidant, health of nervous system; Source - Sunflower seeds

• Vitamin K: Function - Protects the heart, helps build bones; Source - Leafy greens

Water Soluble Vitamins

• Vitamin B: Function - Forming red blood cells, nervous system maintenance; Source - Animal products

• Vitamin C: Function - Forms a protein to make skin, tendons, and ligaments; Source - Berries, peppers; Deficiency - Scurvy

Minerals

• Calcium: Function - Keeps bones and teeth strong; Source - Dairy, fish, kale; Deficiency - Osteoporosis

• Zinc: Function - Immune system support, body development; Source - Animal proteins & nuts

• Iron: Function - Component of hemoglobin that carries oxygen from lungs to body; Source - Green vegetables, lentils; Deficiency - Iron Deficient Anemia (fatigue, depression, shortness of breath)

• Fluorine: Function - Prevents dental cavities; Source - Sunflower seeds, fresh fruits; Deficiency - Cavities & osteoporosis

Canada’s food guide 4 reccomendations

1. Eat More Fruits & Vegetables: Half your plate should be fruits or veggies at every meal.

   • Benefits: Nutrient-dense, rich in vitamins, minerals, fiber, and antioxidants; supports immune system & digestion.

2. Whole Grains: Quarter of your plate should be whole grains.

   • Benefits: Sustained energy, supports heart & digestive health.

3. Eat Plant-Based Protein: Protein foods should make up a quarter of your plate, focusing on plant-based options.

   • Benefits: Muscle maintenance, heart health.

4. Water as Drink of Choice: Drink water regularly, limit sugary drinks, alcohol, and high-calorie beverages.

   • Benefits: Hydration, weight management.

Model Comparisons

• 2007 Rainbow Model: 4 food groups, specific daily servings, emphasized water as beverage.

• 2019 Guide: Focus on serving size vs. proportion, plant-based emphasis, milk as a beverage.

• 1992 Guide: Lacked guidance on environmental impact or cultural food diversity, did not address processed foods.

Digestive System

• Teeth: Mechanically break down food, increase surface area, mix with saliva.

• Mouth: Ingests, chews, mixes food with saliva for starch digestion, forms bolus.

• Epiglottis: Prevents food/liquids from entering trachea, directs food to esophagus.

• Esophagus: Transports bolus to stomach via peristalsis, sphincter prevents reflux.

• Trachea: Conducts air (respiratory, not digestive), adjacent to esophagus.

• Large Intestine: Absorbs water/electrolytes, compacts/stores feces, hosts bacteria.

• Stomach: Stores, mixes, digests food into chyme, secretes gastric juice.

• Small Intestine: Digests/absorbs nutrients using enzymes and bile.

Digestive Illnesses

• GERD: Stomach acid flows back into esophagus due to weak sphincter, causing heartburn, regurgitation, chest pain.

• Lactose Intolerance: Insufficient lactase enzyme, undigested lactose ferments, causing bloating, diarrhea, abdominal pain.

Energy Allocation

Energy Allocation

• Food Digestion: 10%

• Physical Activity: 20-30%

• Functioning Organs: 60-70%

Energy Balance Scenarios

• ENERGY IN = ENERGY OUT: Weight remains stable (caloric balance).

• ENERGY IN > ENERGY OUT: Weight gain (excess calories stored as fat).

• ENERGY IN < ENERGY OUT: Weight loss (body uses stored fat/muscle).

Calories per Gram

• Fat: 9 calories/gram

• Protein: 4 calories/gram

• Carbohydrates: 4 calories/gram

Factors in Maintaining Energy Balance

• Dietary Intake: Quantity/quality, macronutrient thermic effects, eating habits.

• Basal Metabolic Rate (BMR): Body composition, age/sex, genetics, hormones.

• Physical Activity: Exercise, NEAT (non-exercise activity thermogenesis), sedentary behavior.

• Environmental/Lifestyle: Food access, stress/sleep, climate.

• Health/Medical: Illnesses, medications.

• Psychological: Emotional eating, awareness/tracking.