Essential Nutrients in Human Health

Essential Nutrients

• Essential nutrients are compounds that the body can't make or can't make in sufficient quantity.
• These nutrients must come from food and are vital for disease prevention, growth, and good health.

Macronutrients and Micronutrients

• Macronutrients are nutrients that the body needs in large amounts, providing energy (calories).
• Examples of macronutrients: carbohydrates, proteins, and fats.
• Micronutrients are nutrients that the body needs in smaller amounts.
• Examples of micronutrients: water-soluble vitamins, fat-soluble vitamins, minerals, and electrolytes.

Protein

• Found throughout the body, making up enzymes, hemoglobin, and other tissues.
• The body needs protein to grow and repair cells, and to work properly.
• Protein is made from 20+ basic building blocks called amino acids.
• There are 9 essential amino acids that must come from food.

Protein Sources

• Animal products (e.g. chicken, beef, fish, dairy) have all essential amino acids and are considered "complete" protein.
• Plant proteins (e.g. beans, lentils, nuts, whole grains) usually lack at least one essential amino acid and are considered "incomplete" proteins.

Carbohydrates

• Carbohydrates are sugar molecules, broken down into glucose, which is the main source of energy for the body's cells.
• There are three main types of carbohydrates: sugars, starches, and fiber.
• Examples of simple carbohydrates (sugars): glucose, fructose, galactose.
• Examples of complex carbohydrates (starches): bread, cereal, pasta, potatoes, peas, and corn.
• Fiber is a complex carbohydrate that cannot be broken down by the body, and is found in plant-based foods.

Fiber

• Eating foods with fiber can help with feelings of fullness, prevent stomach or intestinal problems, and lower cholesterol and blood sugar.
• Recommended daily intake of fiber: 25g for adult females, 38g for adult males, and less for people over 50 years old.

Soluble and Insoluble Fiber

• Soluble fiber dissolves and creates a gel that may improve digestion, reduce blood cholesterol and sugar, and help with blood glucose control.
• Insoluble fiber attracts water into the stool, making it softer and easier to pass, and helps with bowel health and regularity.

Functions of Carbohydrates

• Provide energy, store energy, build macromolecules, and spare protein and fat for other uses.
• Glucose energy is stored as glycogen, mainly in the muscle and liver.

Fat

• Dietary fat is the most calorically dense of all the macronutrients.
• Fat is used as an energy source, and is necessary for the body to absorb vitamins, minerals, and other nutrients.
• The building blocks of fat are fatty acids and glycerol.

Types of Fat

• Saturated fats: have no double bonds between carbon atoms, and are found in animal sources and some plant-based sources.
• Unsaturated fats: have one or more double bonds between carbon atoms, and are found in plant-based sources.
• Trans fats: created artificially by hydrogenation, and are found in processed foods.

Cholesterol

• A waxy substance essential for many biochemical processes and hormone production.
• The cholesterol in the body is mostly made in the liver.
• There are three types of cholesterol: HDL, LDL, and VLDL.

Functions of Fat

• Lubrication of body surfaces, components of cell membrane structures, formation of steroid hormones, energy storage, insulation, and carrying fat-soluble vitamins.