¡Descarga Understanding Fats: Types, Roles, and Essential Fatty Acids y más Diapositivas en PDF de Biología solo en Docsity! Chapter -9- Fat Prepared by: Jessica Maalouf Fall 2022-2023 Outline • Definition ( Zeinab ) • Types of lipids ( Gaelle ) • Roles of lipids ( lynn ) • What are fatty acids? ( Pamela ) • Types of fatty acids ( Catalina ) • Degree of unsaturation ( Rosemary ) • Food sources of fat ( Carine ) • Recommendations of fat intake ( Vanessa ) • Fat exchange list ( Rami ) 2. Phospholipids: Only around 2% of the dietary lipids are phospholipids. They exist in both plants and animals and are water soluble. Phospholipids are essential to form a protective barrier for your body’s cells. In fact, they are synthesized in the body to form cell and organelle membranes. Phospholipids build structures in blood and body fluids where fat is contained and carried throughout the bloodstream. 3. Sterols : The least frequent kind of lipid is sterol. The most well-known sterol is probably cholesterol. Despite its infamous reputation, the body only obtains a small portion of its cholesterol from food, the majority is produced by the body. Cholesterol is an important component of the cell membrane and is necessary for the synthesis of bile salts, vitamin D, and sex hormones. ROLES OF LIPIDS 1. Storing energy: Fats provide about double of the amount of energy provided by carbohydrates. 2. Regulating and signaling: Lipids are important for regulating the internal conditions such as body temperature, hormones, sustaining nerve impulse transmission, memory storage, and tissue structure. 3. Insulating and protecting: The visceral fats and subcutaneous fats. 4. Transporting: The presence of fat allows the transport of fat soluble nutrients like vitamins A,D,E and K. Fats. What are essential fatty acids ? • Your body can make most of fatty acids it needs from other fats . However , there are two types of fatty acids that your body is unable to synthesize : Linoleic acid (Omega-6 fatty acids ) Alpha linolenic acid (Omega-3 fatty acids ) They considered essential fatty acids because you need to obtain them through your diet since your body can’t create them . Fatty acids in nutrients Fatty acids chemical group FATTY ACIDS TYPES OF FATTY ACIDS • Saturated fats According to the degree of unsaturation, saturated fatty acids are fatty acids that contain ( only C — C single bonds in the carbon chain ) no double bound their hydrocarbon chain. Saturated fatty acids are present mainly in foods of animal origin • Unsaturated fats Contains one or more double bond in their carbon chain (when they contain C — C double bonds ) Unsaturated fats contain fatty acids and can be monounsaturated or polyunsaturated. The carboxyl group and a carbon chain; all hydrogen present = saturated fat Carboxyl group and 1 hydrogen missing on a carbon chain = monounsaturated fat Carboxyl group and multiple hydrogen atoms missing on the carbon chain = polyunsaturated fat Monounsaturated fat is found in high content in olive, peanut, and canola oils. Polyunsaturated fat food sources include soybean, sunflower, fish and corn oils. Lowering the intake of saturated fats in the diet, using mono- and polyunsaturated fats instead, lowers the risk of heart disease. Foods that are high in saturated fats include: • fatty cuts of meat and processed meat products like bacon, sausages and salami • Cream, butter, cheese • coconut oil and palm oil • coconut milk and cream • ice cream • cakes, biscuits and pastries • chocolate and chocolate spreads 2. POLYUNSATURATED FATS are found in high concentrations in • Sunflower, corn, and soybean oils • Walnuts • Flax seeds • Fatty fish (salmon, tuna, mackerel, herring, trout, sardines) and fish oil • Soymilk • Omega-3 fats are an important type of polyunsaturated fat. • The body can’t make these, so they must come from food. • Saturated fat is mainly found in animal foods, but a few plant • foods are also high in saturated fats, such as coconut, coconut oil, and palm oil. Pizza and cheese Whole and reduced fat milk, butter and dairy desserts Meat products (sausage, bacon, beef, hamburgers) Cookies and other grain-based desserts A variety of mixed fast food dishes Sources of Saturated fats: Sources of Trans fats • Small amounts of naturally occurring trans fats can be found in meat and dairy products but it's artificial trans fats that are considered dangerous. • Trans fat – primary sources include: Commercially-baked pastries, cookies, doughnuts, muffins, cakes, pizza dough Packaged snack foods (crackers, microwave popcorn, chips) Fried foods (French fries, fried chicken, chicken nuggets) Anything containing hydrogenated vegetable oil, even if it claims to be “trans fat-free” It is important to read nutrition labels on foods. This will help you know what kinds of fats, and how much, your food contains. Trans fats are known to have harmful health effects. You should avoid foods made with hydrogenated and partially hydrogenated oils (such as hard butter and margarine). They contain high levels of trans- fatty acids FAT EXCHANGE LIST Within a food group, exchanges are servings of food that have similar amounts of carbohydrate, fat, protein, and calories. The exchanges can be used to create a healthy meal plan that will help you keep your blood sugar levels within the recommended range. MONO- UNSATURATED FATS Note that each serving contains: 0 g carbohydrate, 0 g protein, 5 g fat, 45 calories POLY- UNSATURATED FATS Note that each serving contains: 0 g carbohydrate, 0 g protein, 5 g fat, 45 calories
