Nutrients And their functions Unit 1

Macro V Micro MACRO NUTRIENTS – Refers to nutrients made up of large molecules that are required by the body in high quantities in order to perform necessary functions such as provision of energy. Eg? MICRO NUTRIENTS – Refers to nutrients that are small in size and only needed in small quantities for the functions they perform. Eg?

Nutrients Required for Optimal Health Nutrient Groups Macronutrients Carbohydrates Protein Lipids Micronutrients Vitamins Minerals Water

Carbohydrates We have 3 groups: * Simple CHO (sugars): * Complex CHO (starches): * Fibre:

Carbohydrates Glycaemic Index * Glycaemic Index is a measure of the effect that a carbohydrate containing food has on blood glucose levels compared to eating pure glucose. * Foods are given a rating between 0 and 100, with pure glucose having a rating of 100.

Carbohydrates Glycaemic Index High GI: Medium GI: Low GI:

Carbohydrates Fibre Fibre is a type of carbohydrate that the body does not digest. There are two types: soluble and insoluble. Insoluble fibre: Soluble fibre:

Protein * Essential Amino Acids: 8 amino acids that the body cannot make itself; * Complete Protein: mainly from animal sources – meat, fish, eggs, milk; * Incomplete Protein: mainly from plant sources – nuts, grains, legumes;

Protein Humans need to eat protein daily. Complete proteins: Incomplete proteins:

Lipids We have 4 groups: 1. Saturated Fats: 2. Trans Fats : 3. Monounsaturated Fats: 4. Polyunsaturated Fats:

Lipids

Nutrients Required for Optimal Health Cholesterol Cholesterol is a type of fat that is crucial to many metabolic functions; It is an essential part of all cell membranes, hormones and tissues; After consumption of dietary fat, cholesterol is produced by the liver; It is then absorbed into the bloodstream and taken around the body; Therefore, saturated fat increases cholesterol in the blood; A high level of cholesterol in the blood is a major risk factor for CVD.

Water Essential and major component of every cell in the body Functions: Can be obtained from most fruits and vegetables

Minerals Calcium Functions: Sources: * Forms rigid framework of the body (bones, teeth); * Works in conjunction with phosphorus to create strength; * Nerve and muscle functioning; * Involved in blood clotting * Secretion of enzymes. Sources:

Minerals Phosphorous Functions: Sources: * Most of the phosphorus in the body is combined with calcium in the bones; * Involved in metabolism of CHO, fats and proteins; * Involved in activity of many enzymes. Sources:

Minerals Iron Functions: Sources: * Formation of haemoglobin to carry oxygen in the blood; * Formation of myoglobin which stores oxygen in muscle cells; * A component of enzymes; * Haem iron is more readily absorbed than non-haem iron. Sources:

Minerals Fluoride Functions: Sources: * Strengthen tooth enamel against dental caries; * Only effective on teeth that are developing; * Protective role against osteoporosis. Sources:

Minerals Iodine Functions: Sources: * Necessary for formation of thyroxine which regulates metabolism; * An essential part of extra-cellular fluid Sources:

Minerals Sodium Functions: Sources: * Extracellular fluid; * Necessary for nerve transmission * Muscle contractions. Sources:

Vitamins Vitamin A Functions: Sources: * Necessary for healthy lining cells , for example skin and hair; * Maintains normal vision; * Essential for bone and teeth formation. Sources:

Vitamins Vitamin D Functions: Sources: * Increases the absorption rate of calcium and phosphorous; * Controls the movement of calcium and phosphorous in and out of bones; * Ultraviolet light causes vitamin D to by synthesised by the skin. Sources:

Vitamins Vitamin C Functions: Sources: * Also called Ascorbic Acid; * Formation of connective tissue that holds cells together; * Involved in maturation and strength of collagen; * Its presence increases the absorption of iron. Sources:

Vitamins Vitamin B Group Functions: Required for enzyme which release energy from carbohydrates Enzymes associated with energy metabolism and cell respiration Promotes cell growth and development Sources:

Vitamins Folate Functions: formation of DNA during growth; red blood cell and anti body formation. Sources: