Fats Are all fats bad for us?

What is Cholesterol A fatlike substance that is vital for life Every cell in your body contains cholesterol We do not need to include cholesterol in our diet. We get more cholesterol when we eat foods of animal origin. No cholesterol is found in foods in plant origin

LDL vs. HDL cholesterol Low-density lipoproteins (LDL) carry cholesterol from the liver to the rest of the body. Cells latch onto these particles and extract fat and cholesterol from them. When there is too much LDL cholesterol in the blood, these particles can form deposits in the walls of the coronary arteries and other arteries throughout the body. Such deposits, called plaque, can narrow arteries and limit blood flow. When plaque breaks apart, it can cause a heart attack or stroke. Because of this, LDL cholesterol is often referred to as bad, or harmful cholesterol. High-density lipoproteins (HDL) scavenge cholesterol from the bloodstream, from LDL, and from artery walls and ferry it back to the liver for disposal. Think of HDL as the garbage trucks of the bloodstream. HDL cholesterol is often referred to as good, or protective, cholesterol. Several strategies can help you lower the amounts of total and harmful LDL cholesterol in your bloodstream, and thus your risk of heart disease.

Arteries with plaque from too much cholesterol

Main functions of fats Add flavor and tender texture to food. Satiety- takes the body longer to digest fats so we feel fuller longer Fats are also important for delivering fat soluble vitamins such as Vitamins A, E, D, and K. Fats are the most calorie dense compound in food They have over twice the calories per gram of proteins or carbohydrates.(9 calories per gram vs. 4 calories per gram)

Saturated Fat vs. Unsaturated Fat Saturated fat causes the level of cholesterol in the blood to rise higher than normal. Unsaturated fat does not cause the blood cholesterol levels to rise as much.

Saturated Fat Saturated Fat function: Saturated Fat sources: Increases blood cholesterol levels. Saturated Fat sources: Can be found in some vegetable oils, such as coconut and palm oils (tropical oils). Butter is high in saturated fat, while margarine tends to have more unsaturated fat. Most saturated fats tend to be solid at room temperature, with the exception of tropical oils.

Mono-Unsaturated Fats • Function: tends to lower LDL cholesterol (the "bad" cholesterol) • Sources: found in both plant and animal products-olive oil, canola oil, peanut oil, and avocado.

Poly-unsaturated fats Function: tends to lower blood cholesterol levels.(both HDL and LDL) Sources: found mostly in plant sources-safflower, sunflower, soybean, corn, cottonseed oil.

Trans Fat Function of Trans fat Trans fats raise LDL cholesterol levels. LDL is the bad carrier for cholesterol. Trans fats may also lower HDL cholesterol. HDL is the good carrier for cholesterol. Foods containing hydrogenated fat do not go stale as quickly as foods containing unsaturated fat. Foods made with it can stay on supermarket shelves longer. It gives commercially prepared foods a taste and texture similar to regular fat. It is less expensive than butter and more stable than unsaturated fat. Hydrogenated vegetable oil is often chosen for deep-frying. Many restaurants use it.

Food sources of trans fat Trans fats are found in foods made with or cooked in hydrogenated vegetable oil. These include crackers and fried snack foods, such as potato chips. Trans fats are found in baked goods, such as cookies, cakes, and doughnuts. Margarine and hydrogenated vegetable shortening also contain trans fats

Omega-3 Fats Functions Omega-3 fatty acids are considered essential fatty acids Also known as polyunsaturated fatty acids -omega-3 fatty acids play a crucial role in brain function, as well as normal growth and development. They have also become popular because they may reduce the risk of heart disease. Research shows that omega-3 fatty acids reduce inflammation May help lower risk of chronic diseases such as heart disease, cancer, and arthritis. Omega-3 fatty acids are highly concentrated in the brain and appear to be important for cognitive (brain memory and performance) and behavioral function.

Omega- 3 Food Sources The American Heart Association recommends eating fish (particularly fatty fish such as mackerel, lake trout, herring, sardines, albacore tuna, and salmon) at least 2 times a week.

Chemical Composition of Fats