Human Body Systems and Nutrition Overview

Human Body Systems Overview

• Cardiovascular System (Arteries, Capillaries, Veins): The human body contains 100,000 km of arteries, capillaries, and veins.

• Digestive System Length: The average person's digestive system tube measures 9 meters in length.

• Respiratory System: A person breathing approximately 15 times a minute will take around 800 million breaths by age 100.

Taste Sensitivity (Supertasters)

• Supertasters: Individuals with more fungiform papillae (taste buds) are supertasters and have heightened taste sensitivity.

• Supertaster Dislikes: Common strong-tasting foods like coffee, Brussels sprouts, grapefruit juice, spinach, and carbonated drinks are often disliked by supertasters.

Nutrition and Digestion

• Basic Needs: Food provides nutrients for energy and growth, leading to overall good health.

• Types of Nutrients: Six essential nutrients are carbohydrates, proteins, fats, vitamins, minerals, and water.

• Macronutrients: Carbohydrates, proteins, fats, and water are required in large quantities daily.

• Micronutrients: Vitamins and minerals are required in smaller quantities daily.

Digestive System Function

• Breaking Down Macromolecules: The digestive system breaks down large food molecules into smaller, usable parts.

• Nutrient Absorption: Smaller molecules easily pass through cell membranes for absorption.

Nutrient Breakdown and Building Blocks

• Nutrient Composition: Most foods contain complex molecules that must be broken down into smaller molecules for the body to use.

• Amino Acids (Proteins): Proteins are large molecules made from 20 different amino acids, crucial for building body structures.

• Essential Amino Acids: Eight amino acids must be obtained from food, often found in animal products. Vegetarians can obtain them from a combination of foods..

Carbohydrates

• Structure: Carbohydrates are made of carbon, hydrogen, and oxygen.

• Energy Source: Carbohydrates are a major energy source, stored as glycogen in the liver and muscles for quick energy release.

• Excess Carbohydrates: Excess carbohydrates are stored as fat.

• Types of Carbohydrates: Simple sugars (glucose) and complex carbohydrates (starches) are broken down into simple sugars for use. Cellulose (fiber) cannot be broken down.

• Fiber (Cellulose): Fiber is essential for digestion and may reduce heart disease risk.

Proteins

• Function: Proteins are vital for all bodily functions, forming structures, storing nutrients, defending against pathogens, and facilitating cellular communication.

• Amino Acids: Proteins are composed of chains of 20 different amino acids.

• Enzyme Function: Enzymes, which are proteins, speed up chemical reactions.

Fats (Lipids)

• Energy Storage: Fats are a concentrated energy source. Fats cushion organs and insulate the body

• Types of Fats:

• Saturated Fats: Primarily found in animal products, linked to high cholesterol and heart disease.

• Unsaturated Fats: Found in plants and fish; essential for a healthy diet.

• Trans Fats: Partially hydrogenated unsaturated fats, solid at room temperature, associated with heart disease.

Vitamins and Minerals

• Vitamins: Organic molecules crucial for various bodily functions and for assembly of other molecules.
• Water-Soluble: Vitamins C and the B vitamins are eliminated in urine and need to be replenished every day.
• Fat-Soluble: Vitamins A, D, E, and K can be stored in the body.
• Minerals: Inorganic nutrients that participate in many bodily functions. Minerals are lost through sweat and urine, daily intake is needed.

Water

• Importance: Water is the most important nutrient, vital for all bodily processes.

• Daily Needs: The human body requires at least one litre per day.

• Dehydration: Inadequate water intake can lead to dehydration and disruption of bodily functions.