Food Nutrients.docx

Carbohydrates o o -

Fuel – energy All cells use energy: Heart Breathing Digestion Brain

o Carbs – sugars – dispensed around the body o Every normal body functioning comes from energy from the carbohydrates o Wide range of sugars and starches found in a variety foods o Classified into 3 groups: - Monosaccharides - Disaccharides - Polysaccharides Monosaccharides - There are 3 sugars that make up carbohydrates they are: glucose, fructose and galactose - They are single sugar molecules and all have similar chemical structures - Monosaccharides are the simplest carbohydrates o Fructose – found in fruit o Glucose – jellybean o Galactose – dairy Disaccharides - Sucrose, lactose and maltose are 3 sugar molecules made up of different pairs of monosaccharides - Sucrose contains glucose molecules connected to a fructose molecule - Lactose contains glucose molecules connected to a galactose molecule - Maltose consists of two glucose molecules joined together o Sucrose – cake o Lactose – cheese, yogurt o Maltose – bread, malt, sweet potatoes Polysaccharides:

Polysaccharides are monosaccharides that are joined together - Starch is a polysaccharide found in plants to glucose in the gut - Glycogen is a glucose polysaccharide that stores glucose in the liver and muscles - Pectin is a polysaccharide found in the cells of fruits and vegetables o Starch – potatoes, rice, pasta o Glycogen – bananas, papaya, apples o Pectin - Pears, apples, guavas, quince, plums, gooseberries 1

Proteins What are proteins: o Proteins are molecules made up of carbon, hydrogen, oxygen, nitrogen and sulfur. o Each protein consists of chains mostly of carbon in groups called amino acids. o They build in different structures to create different types of proteins.

Structure of proteins: o 22 different amino acids and all have the same basic structure. - This includes amino group (NH2) and carboxyl group (COOH). - Each amino acid has a unique side chain attached. o They can join together in long chains and can form a crumpled threedimensional shape called globular proteins.

Food sources of protein: o Large variety in how much protein each food has. o The body needs all the amino acids to carry out all the protein functions properly. o Some amino acids cannot be synthesised by the body and are called essential amino acids so, if the diet lacks these amino acids, a deficiency may develop. o Some amino acids don’t can be synthesised and are called nonessential amino acids. o A food is considered to provide complete protein is it contains adequate amounts of all eight essential amino acids. o Incomplete protein foods lack one or more essential amino acids. o Limiting amino acids is a food that has all the essential amino acids but not the right quantities.

Vegetarianism o It is possible to maintain a healthy and balanced vegetarian diet. o Adults usually store amino acids.

Unsaturated fatty acids What is it? An unsaturated fat is a type of fat containing a high proportion of fatty acid molecules with at least one double bond, and is considered to be healthier in the diet than saturated fat.

What is its function? Lower cholesterol and lowers risk for heart disease.

What is its structure?

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Food examples Avo, nuts and seeds.

Cholesterols What is it? Cholesterols is another type of lipid (fat) It is a sterol, with a molecular structure very different from that of a triglyceride It is essential for many of body's metabolic processes, including the production of hormones, bile and vitamin D. Cholesterol is produced by the liver and also made by most cells in the body It is carried around in the blood by little ‘couriers’ called lipoproteins

What is its function? All your body cells contain cholesterol. It is needed in your body for: Making bile acids, they break down lipids into your gut during digestion Absorbing and using lipids for your food Making some important hormones Body can make its own cholesterol in the liver Animals can also make their own cholesterol, therefore it is found in animals If you eat a lot of cholesterol in your diet, the amount made in your body usually decreases A high intake of saturated fat, gives you high cholesterol in the blood, which can cause heart disease

What is its structure?

Food examples The cholesterol in your diet comes mainly from eggs and from animal products that are rich in fat such as meats and full fat dairy foods. All foods from animals contain some cholesterol. Foods from plants do not contain cholesterol.

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Saturated Fats What is it? A saturated fat is a type of fat in which the fatty acid chains have all or predominantly single bonds. A fat is made of two kinds of smaller molecules: glycerol and fatty acids.

What is its function? Loss of sufficient saturated fatty acids in white blood cells hampers their ability to recognize and destroy foreign invaders, such as viruses, bacteria, and fungi.

What is its structure? They have as many hydrogen atoms as can fit on the following chain.

Food examples animal fat products such as: cream cheese butter other whole milk dairy products fatty meats which also contain dietary cholesterol.

Dietary fibre Dietary fibre or roughage is the portion of plant-derived food that cannot be completely broken down by digestive enzymes. Dietary fibre isn’t one of the 6 nutrients but is required in our diet to survive. It passes through our digestion and helps with it, but it isn’t used for our body like proteins so isn’t absorbs Fibre helps moving around in an easy manner Peristalsis is the movement of your intestines Reduces constipation

Lipids Lipids are a group of substances that include fats, oils, fatty acids phospholipids, sterols, glycolipids and waxes Fat cells in your diet and are necessary to survive and live healthily Some are plant sources and animal sources There are foods that are better fats than worse (almonds vs fries) Important store of energy, retain body heat and protects organs Lipid = fat= adipose tissue Transports fat soluble vitamins and minerals around the body

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Provides fatty acids and used for brain function Healthy skin and hair They provide 37 kJ per gram

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