Nutrition Chapter 1: Introduction to Nutrition

Introduction to Nutrition

• Nutrition studies the effects of food and drink on the body, emphasizing essential nutrients for health.
• Nutrients are substances providing energy or necessary for growth and repair.
• Six major nutrients: carbohydrates, lipids, proteins, vitamins, minerals, and water.

Aspects of Nutrition Study

• Chemical and physical structure of foods.
• Food production and growth methods.
• Human body interactions with food.
• Nutrient metabolism and physiological needs.
• Nutrient interactions with each other.

Malnutrition

• Refers to deficiencies, excesses, or imbalances in nutrient intake.
• Nutritional situations categorized into optimum nutrition and malnutrition.
• Undernutrition leads to hunger; overnutrition results in excess caloric intake.

Food Quality

• Quality relates to food's taste, texture, appearance, microbial content, and consumer preference.
• High-quality foods significantly provide essential nutrients relative to their calorie content.

Units of Measure

• Weight: 1 kg = 2.2 lbs
• Height: 1 ft = 30.5 cm; 1 inch = 25.4 mm
• Energy: 1 Cal = 4.18 kJ

Lifestyle Factors Affecting Nutrition

• Includes physical activity level, drug use, and sleeping patterns.
• Eating habits encompass what, how much, and how often a person eats.

Chronic Disease

• Defined as health conditions lasting over 1 year requiring ongoing medical care or limiting daily activities.

Achieving a Healthy Diet

• A healthy diet should be adequate, balanced, calorie-controlled, moderated, and varied.

Levels of the Human Body

• Atomic Level: Atoms are basic building blocks.
• Molecule Level: Groups of atoms participating in chemical reactions.
• Cellular Level: Cells are fundamental units containing nucleus, ribosomes, cytoplasm, and DNA.
• Tissue Level: Composed of cells and intercellular substances.
• Whole Body Level: The most abundant element is oxygen.

Weight and Height Indices

• Body Mass Index (BMI): Weight (kg) / Height (m)².
• Underweight: BMI < 18.5; Healthy: 18.5-24.9; Overweight: 25-29.9; Obese: BMI > 30.

Human Body Systems

• Nervous System: Controls body functions.
• Immune System: Protects against diseases.
• Respiratory System: Facilitates breathing.
• Digestive System: Processes food.
• Endocrine System: Regulates hormones.
• Cardiovascular System: Manages heart and blood.
• Reproductive System: Involves sex organs.
• Integumentary System: Protects the outer body.
• Lymphatic System: Waste disposal and protein synthesis.
• Musculoskeletal System: Composed of muscles and bones; total bones = 206.

Water and Electrolytes

• Water composition: 60% in men; 55% in women; recommended intake: 3.7 liters/day for men, 2.7 liters/day for women.
• Common water loss methods: urination, sweating, and metabolism.

Electrolytes

• Electrolytes are charged substances in water, important for various physiological functions.

Essential Fatty Acids

• Essential for hormone synthesis, skin integrity, growth, reproduction, blood clotting, and energy production.
• Omega-3: Found in salmon, walnuts, spinach; supports body maintenance.
• Omega-6: Found in corn oil, walnuts, and sesame oil; crucial for brain function.
• Trans fats are unhealthy fats found in processed foods like fried items and donuts.

Health Consequences of Fat Intake

• Excess fat leads to hypercholesterolemia, obesity, and diabetes.
• Deficiencies may result in itchy skin, diarrhea, delayed growth, poor wound healing, and neurological issues.
• Recommended fat intake: 20-35% of daily calories.