Fats are made of carbon, hydrogen and oxygen. They provide an excellent energy source and are essential for cell structure and function. Saturated and trans fats can raise cholesterol levels while unsaturated fats do not. Unsaturated fats include monounsaturated fats containing one double bond and polyunsaturated fats containing more than one double bond. Omega-3 is a type of polyunsaturated fat important for cell repair that must be obtained through diet or supplements.

1. GCE AS Food Technology Fats (Lipids)

2. Structure Fatty acids are made up of three elements: Carbon Hydrogen Oxygen

3. What does the body use it for? Excellent energy source, with more than twice the energy as either carbohydrates or protein. Essential to the structure and function of body cells Fat soluble vitamins (A D E and K) Insulation Fat is digested slowly by the body and therefore make you feel fuller (satiated) for longer

4. Saturated and Unsaturated Saturated fats and trans fats are "bad" fats as they can raise cholesterol Unsaturated “good” fats are better for you, as consuming foods containing "polyunsaturated" and "monounsaturated" fats does not increase cholesterol.

5. Saturated fat If the fatty acid has all the hydrogen atoms it can hold it is said to be saturated This type of fat is typically found in large amounts in foods from animals, e.g. meat, butter, cheese and cream. Many baked goods such as cakes, biscuits and pastries are also high in saturated fat. Excessive intake of saturated fat can increase blood cholesterol levels.

6. Unsaturated Fat In unsaturated fats, some of the carbon atoms are joined to others by a double bond and, therefore, could accept more hydrogen atoms. This means that they are not completely saturated with hydrogen, so are called unsaturated fats. There are two main types of unsaturated fats - monounsaturated (containing one double bond) and polyunsaturated (containing more than one double bond).

7. Trans-fatty acids “ Bad” fats because they raise cholesterol. Monounsaturated fatty acids Significant amounts in most types of fats of plant origin, such as nuts, avocado pears, rapeseed oil and olive oil. Monounsaturates do not raise blood cholesterol and evidence shows that they reduce blood cholesterol levels if they replace saturated fat in the diet. Polyunsaturated fatty acids From vegetable sources, such as sunflower oil or seeds, but are also found in, nuts, green leafy vegetables and oily fish such as mackerel and sardines. Reduce blood cholesterol levels.

8. Which Fats Are Best? Saturated fats, monounsaturated fats and polyunsaturated fats all have proven health benefits so should be included as part of your diet. Trans fats should be avoided where possible

9. Sources When it comes to dietary fats natural, unprocessed sources are the best foods. - Almonds. - Avocado. - Beef. - Coconut. - Eggs. - Salmon.

10. Omega 3 Fish Oil Type of polyunsaturated fat. Most important fat we need for cell reproduction and repair and for making substances that fight inflammation. Cant make omega 3, has to be taken in through diet or supplement. Naturally found in oily cold water fish like tuna, salmon, and sardines. Vegetable sources include pumpkin seeds, flax seeds, and walnuts. Some products, such as margarine, yoghurts and eggs, are now enriched with omega-3 fats.

11. Exam style Questions Fatty acids are made up of which three elements? Which fats are said to raise cholesterol? What are the two main types of unsaturated fats? What type of fat is omega 3?

12. Answers: Carbon, Hydrogen, Oxygen Saturated and Trans Monounsaturated (containing one double bond) and polyunsaturated (containing more than one double bond Polyunsaturated