Nutrients are substances derived from food that the body utilizes for growth, maintenance, and repair.
There are six classes of nutrients:
- Carbohydrates: Organic compounds composed of carbon, hydrogen, and oxygen. They are the primary
source of energy during metabolism, providing 4 kilocalories per gram. Carbohydrates include
monosaccharides (single sugars like glucose), disaccharides (two linked monosaccharides like sucrose),
and complex polysaccharides (long chains of monosaccharides like starch).
- Proteins: Essential for building and repairing tissues, proteins are composed of amino acids. They also
play roles in enzymes, hormones, and immune function.
- Lipids: Also known as fats, lipids are crucial for energy storage, cell membrane structure, and the
absorption of fat-soluble vitamins. They yield 9 kilocalories per gram.
,- Vitamins: Organic compounds required in small amounts for various metabolic processes. They often
act as coenzymes or precursors to regulatory molecules.
- Minerals: Inorganic elements necessary for various bodily functions, including bone health, fluid
balance, nerve function, and energy production.
- Water: Vital for all body functions, water serves as a solvent, temperature regulator, and medium for
biochemical reactions.
Monosaccharides are simple sugars, such as glucose and fructose, which are the most basic units of
carbohydrates and are readily absorbed into the bloodstream for energy production.
- Glucose
- Fructose
- Galactose
Glucose ✔️Blood Sugar/Dextrose
,1. Main fuel for brain and needed for RBCs
2. Major carbohydrate found in bloodstream
3. Sources include many foods, such as grapes, oranges, corn and carrots
Fructose ✔️Levulose/Fruit Sugar
1. Sweetest Monosaccharide
2. Sources include fruits, honey, and corn syrup
Galactose ✔️Component of Milk Sugar
1. Body converts glucose to galactose in mammary tissue during lactation; makes lactose in breast milk
2. Sources include milk/dairy products
Disaccharides ✔️Double Sugars; made up of two monosaccharides
- Sucrose
- Lactose
- Maltose
, Sucrose ✔️Table Sugar - furnishes 1/3 of total COH intake in the average western diet
1. Made up of glucose and fructose
2. Sources incude sugar beets, sugar cane or maple syrup, fruits and vegetables
Lactose ✔️Milk Sugar
1. Made up of glucose and galactose
2. Sources include milk products
Maltose ✔️Plant Sugar
1. Made up of 2 glucose molecules
2. Appears whenever starch is broken down
Polysaccharides ✔️Complex
- Starch