Lecture on Macronutrients

Introduction

• Presenter: Cathy from Level Up RN
• Focus: Detailed discussion on macronutrients - carbohydrates, lipids, and proteins.
• Includes a knowledge check quiz.

Carbohydrates

• Primary Source of Energy:
  • Controls blood glucose and insulin metabolism.
• Food Sources:
  • Vegetables, fruits, dairy products, whole grains.
• Types of Carbohydrates:
  • Simple Carbohydrates:
    • Easy to digest, quick energy burst.
    • Examples: Fruit juice, honey, candy.
    • Rapid increase in blood glucose levels.
  • Complex Carbohydrates:
    • Rich in fiber, slower digestion.
    • Examples: Apples, brown rice, lentils.
    • Slower increase in blood glucose levels.
• Glycogen:
  • Stored carbohydrate energy in liver and muscles.
  • Released into bloodstream through glycogenolysis during low blood glucose.
• Fiber:
  • Benefits: healthy bacterial growth, softens stool, stabilizes blood glucose.
  • Reduces risk of diverticulitis, hemorrhoids, colorectal cancer, coronary artery disease.
  • Recommended intake: 38g/day for men, 25g/day for women.

Lipids

• Main Source of Stored Energy:
  • Provides cell structure (phospholipid bilayer), temperature regulation, organ protection.
• Food Sources:
  • Fats, oils, dairy, meat.
• Types of Lipids:
  • Saturated Fats:
    • Found in animal products.
    • Increase LDL levels, risk for heart disease.
  • Trans Fats:
    • Found in processed foods (partially hydrogenated oils).
    • Increase LDL, decrease HDL.
  • Unsaturated Fats:
    • Heart-healthy fats found in avocados, nuts, seeds, olive, and vegetable oil.

Cholesterol

• Role:
  • Component of cell membranes, vitamin D, hormone synthesis, and digestion.
• Types:
  • LDL (Low-Density Lipoproteins): Bad cholesterol.
  • HDL (High-Density Lipoproteins): Good cholesterol.
• Recommended Intake:
  • Generally below 300mg/day; below 200mg/day for high-risk individuals.

Proteins

• Importance:
  • Tissue building and repair, immune system, energy.
• Food Sources:
  • Seafood, meat, poultry, eggs, soy, nuts, seeds, dairy.
• Amino Acids:
  • 9 essential (must get from diet), 11 non-essential (produced by body).
  • Complete Proteins: Contain all 9 essential amino acids (e.g., meat, soy).
  • Incomplete Proteins: Lack one or more essential amino acids, can be combined for completeness (e.g., rice and beans).
• Protein Metabolism:
  • Anabolism: Protein synthesis (assembling amino acids).
  • Catabolism: Protein breakdown for energy.
  • Nitrogen Balance:
    • Neutral in healthy adults.
    • Positive during growth spurts, pregnancy.
    • Negative in starvation, severe injuries.

Quiz Questions

1. What is the stored carbohydrate energy in the liver and muscles?
   • Answer: Glycogen.
2. Which macronutrient is the main source of stored energy in the body?
   • Answer: Lipids.
3. What do you call the breakdown of protein for energy?
   • Answer: Catabolism.

Conclusion

• Encouragement to review the material and provide feedback.
• Emphasis on repetition for learning.