Food Nutrients

Carbohydrates

Carbohydrates Main source of chemical energy in food Come in different sizes and complexity

Monosaccharides, disaccharides, polysaccharides

Glucose is the most common monosaccharide

Types of Carbs Glucose is used in cellular respiration to

break down into energy molecules (adenosine triphosphate or ATP)

Lactose and Sucrose are common disaccharides (are digested into glucose molecules)

Cellulose and glycogen are common polysaccharides stored in plants and animals respectively

Carbs in diet and living tissues Most are used for energy by catabolic

reactions to form glucose subunits Some are stored in muscles and in the

liver as glycogen If not utilized then converted into fats

(lipids)

Proteins

Proteins Most diverse and complex

macromolecule Used for variety of functions and

structural components Made of long chains of amino acids

20 a.a. all together, 8 of them are essential; meaning that the have to be obtained through diet

Functions Enzymes – control/catalyze chemical

reactions Myosin – protein responsible for muscle

contraction Haemoglobin – transport O2 in blood Collagen – connective tissue in skin HGH – human growth hormone Antibodies – immune signalers

Lipids

Components of lipids Main subunit is a triglyceride

Saturated – solid fats at room temperature Unsaturated – liquids at room temperature

Lipids Concentrated chemical energy Used for absorbing vitamins, making sex

hormones (estrogen and testosterone) and main component of cell membrane (phospholipid bilayer)

Common lipids Some (like amino acids) are essential

ie; Omega – 3 fatty acid . . . Good for heart health and arthritis

Steroids are made of fats (sex hormones)

Cholesterol (both good and bad types); used for cell membrane structure

Vitamins

Vitamins Vitamins are used for regulating cell

functions, growth and development Either fat soluble or water soluble Vit. A,D,E and K are fat soluble and are

stored in fat tissue (not easily eliminated and can be toxic if levels are high)

Vit. B and C are water soluble, passed in urine and need to be replenished daily

Minerals Elements that the body uses to carry

out cellular functions Sodium – used for muscle contraction

and nerve impulses Iron – O2 binds to it in haemoglobin Many others as well . . .