Final Review and Assessment of Profile and Nutritional Health – FSM 159 Nutrition - 30 points After you have completed your IProfile analysis and your personal iProfile questions - you must now review

Examples: corn, safflower, and sunflower oil o Monounsaturated fatty acid: single double bond in the carbon chain. Examples: canola, olive and peanut oil. o Polyunsaturated fatty acid: two or more double bonds in the carbon chain. o Plant foods are generally high in unsaturated fatty acids. o Omega -6 polyunsaturated linoleic fatty acid: first double bond is between the sixth and seventh carbon atoms. Examples: co rn oil, safflower oil, soybean oil and nuts. o Omega -3 polyunsaturated linolenic fatty acid: the first double bond is between the third and fourth carbon atoms. Examples: flaxseed oil, canola oil and nuts.

Fish oil is high in longer chain omega -3 fatty acids . • Essential fatty acids: must be consumed in the diet because they cannot be made by the body or cannot be made in sufficient quantities. o Linoleic (omega -6). Found in vegetable oils such as corn and safflower oil. ▪ Arachidonic acid: synthesized from linol eic acid; found in both animal and plant fats. o Alpha -linolenic (omega -3). Found in nuts, flaxseed, and canola oil. ▪ Eicosapentenoic acid (EPA) and docosahexaenoic acid (DHA); synthesized from alpha -linolenic acid; found in fatty fish • The fats and oils in our diets contain combinations of saturated, monounsaturated, and polyunsaturated fatty acids. • The types of fatty acids in a triglyceride determine the texture, taste and physical characteristics of the food. • Hydrogenatio n is the process used to make partially hydrogenated oils in which hydrogen atoms are added to the carbon –carbon double bonds of unsaturated fatty acids, making them more saturated. Trans fatty acids are formed during the process. o Cis fatty acids: hydrogen atoms are on the same side of the double bond making the carbon chain bent; the primary form in nature o Trans fatty acids: hydrogen atoms are on opposite sides of the double bond making the carbon chair straighter and taking on the characteristics of saturated fatty acids; primarily occurs in manufactured fats Trans fat in the News • The margarine vs. butter recommendations are good examples of how nutritional information changes. When saturated fats were linked with health problems, it was thought that making h ealthier unsaturated fats “spreadable” would be better. When research suggested that trans fats were less healthy than saturated fat, the n butter seemed like the better choice. Now, trans -fat free margarine is available. Trans fat vs. Palm Oil • Students could be assigned to read about the palm oil and rainforest connection Test Your Understanding • These slides are designed to test students’ knowledge of previous concepts. These could be used with clickers, color -coded voting cards, or fingers. These questions could also be passed out and done as individual or group quizzes. Phospholipids • Phospholipids contain the backbone of glycerol and two fatty acids. In place of the third fatty acid is a chemical group containing phosphorous (phosphate gr oup). • Fatty acids at one end of the molecule are soluble in fat. • The phosphate containing group is soluble in water. • Can act as emulsifiers . Emulsifiers allow fat and water to mix. • Lecithin is a phospholipid. Sources: eggs and soybeans o The food industry u ses lecithin as an emulsifier in margarine, salad dressings, chocolate, frozen desserts and baked goods. o In the body, lecithin is a major constituent of cell membranes. It is also used to synthesize the neurotransmitter acety lcholine, which activates muscles and plays a role in memory. • Phospholipids are an important component of cell membranes. They form a double - layered sheet called the lipid bilayer by orienting the water -soluble, phosphate - containing “heads” toward the aqueous (water) environments inside and outside the cell and the fatty acid “tails” toward each other to form the lipid center of the membrane. • Phospholipid structure supports its function because it allows one end of the molecule to be soluble in fat, while the o ther end is soluble in water . • The salad dressing shown does not contain an emulsifier, so it separates into layers of oil and vinegar and must be shaken before it is poured on a salad. Many salad dressings are emulsified so that they do not separate when left standing. Sterols • Rings of carbon atoms form the backbones • Cholesterol is the best -known sterol. It is not essential because the body manufactures it in the liver. o More than 90% of the cholesterol in the body is found in cell membranes. o Also part of the myelin on many nerve cells. o Cholesterol is needed to synthesize other sterols, including Vitamin D. o Cholesterol is found only in foods from animal sources. • Plant sterols help form plant cell membranes. Found in small quantities in most plant foods. o When consumed in the diet, help to reduce cholesterol levels in the body. Concept Check • How are phospholipids and cholesterol similar and different? • W hat is an example of a non -essential nutrient? o Both phospholipids and cholesterol are found in animal cell membranes and are used to make other materials. Cholesterol and omega -6 fats are two examples of non -essential nutrients so far in this chapter. This can be done in pairs or groups, as a think -pair -share activity, or as a whole -class discussion. Digestion and A bsorption of Fat • Most fat digestion and absorption occur in the sma ll intestine . • A small amount of lipid digestion occurs in the stomach due to lipases produced by the mouth and stomach. • The liver produces bile, which is stored in the gallbladder and released into the small intestine. • The pancreas produces the enzyme pancreatic lipase, which is released into the small intestine to break down triglycerides into monoglycerides, fatt y acids, and glycerol. • In the small intestine, the products of fat digestions and bile form micelles, which allow lipids to diffuse into the mucosal cells. • Inside the mucosal cells, fatty acids and monoglycerides are reassembled into triglycerides and inco rporated into lipid transport particles, which enter the lymph. • Fat absorption in the small intestine is efficient. Little fat is lost in the feces. • Bile acts an emulsifier, breaking down large lipid droplets into small globules. • The triglycerides in the globules can then be digested by enzymes from the pancreas. • The resulting mixture of fatty acids, monoglycerides, cholesterol, and bile forms smaller droplets called micelles, which facilitate absorption. • The bile in the micelles is also absorbed and retur ned to the liver to be reused. • Once inside the mucosal cells of the intestine, the fatty acids, cholesterol, and other fat - soluble substances must be further process before they can be transported in the blood. Transporting Lipids in the B lood • Lipoprotein : particles made up of a water -soluble envelope of protein, phospholipids, and cholesterol. • Different types of lipoproteins transport dietary lipids from the small intestine to body cells, from the liver to body cells, and from body cells back to the liver for disposal. Lipoprotein Structure • A lipoprotein consists of a core of triglycerides and cholesterol surrounded by a shell of protein, phospholipids, and cholesterol. • Phospholipids orient with their fat -soluble “tails ” toward the interior and their water - soluble “heads ” toward the outside. • This allows fat -soluble substances in the interior to travel through aqueous blood. Types of Lipoproteins o Chylomicrons: lipoproteins that transport lipids from the mucosal cells of the small intestine and deliver triglycerides to other body cells. These are the largest particles and contain the greatest proportion of triglycerides. o Very -low -density lipoproteins: made in the liver and transport triglycerides and deliver them to the cells. These are smaller than chylomicrons but still contain a high proportion of triglycerides. o Low -density lipoproteins transport and deliver cholesterol to the cells. These contain a higher proportion of cholesterol than do other lipoproteins. o High -density li poproteins help return cholesterol to the liver for reuse or elimination. These are high in cholesterol and are the densest lipoproteins due to their high protein content. Lipid functions • Diet: fat is needed to absorb fat -soluble vitamins; it is a source of essential fatty acids and energy. • In the body: lipids form structural and regulatory molecules and are broken down to provide ATP (energy). o Triglycerides found in oils lubricate body surfaces, keeping the skin soft and supple. • Adipose tissue: the prim ary storage form of triglyceride in the body, cushions our internal organs, and insulates the body from changes in temperature. o The amount and location of adipose tissue affect body size and shape. o Cells contain large droplets of triglyceride. As weight i s gained, the triglyceride droplets enlarge. Role of Essential Fatty A cids • Essential fatty acids are important for health: o needed for the formation of phospholipids. o essential for growth, development, fertility and maintaining the structure of red blood cells and cells in the skin and nervous system. • Omega -3 fatty acid DHA is important in the retina of the eye. • DHA and omega -6 fatty acid arachidonic acid are needed to synthesize cell membranes in the nervous system and important for normal brain dev elopment in young children. • Needed to prevent essential fatty acid deficiency – a condition characterized by dry, scaly skin and poor growth. • Eicosanoids: hormone like molecules made from omega -3 and omega -6 polyunsaturated fatty acids. Help regulated bloo d clotting, blood pressure, immune function, and other body processes. • Increasing consumption of foods rich in omega -3 fatty acids increases the proportion of omega -3 eicosanoids. This reduces the risk of heart disease by decreasing inflammation, lowering blood pressure, and reducing blood clotting. Fat as a Source of E nergy • Depositing fat in adipose tissue is an efficient way to store energy. Each gram of fat provides 9 Calories. • Feasting: consuming more calories than needed. The excess is stored primari ly as fat. • Fasting: consuming fewer calories than needed. An enzyme inside of fat cells receives a signal to break down stored triglycerides . The fatty acids and glycerol are released directly into the blood and circulate throughout the body. Lipids in H ealth and D isease Heart Disease • Cardiovascular disease: any disease that affects the heart and blood vessels. Number - one cause of death for both men and women in the United States • Atherosclerosis: type of cardiovascular disease in which cholesterol is de posited in artery walls, reducing elasticity and eventually blocking the flow of blood. • Development of atherosclerosis: begins with inflammation • Risk factors for heart disease: o Obesity: increases risk of increased blood pressure, blood cholesterol and diabetes; increases the amount of work the heart muscle must do o Diabetes: damages vessel walls o High blood pressure: damage vessel walls; forces the heart do work harder o Gender: men are generally affected a decade earlier than women o Age: inc reased risk for men over age 45 and women over age 55 o Family History: increased risk if a male family member exhibited heart disease before age 55 or a female family member before age 65; African Americans have higher risk due to high incidence of high blo od pressure o Lifestyle: smoking increases risk; exercise decreases risk by reducing blood pressure, increasing health HDL cholesterol levels, reducing diabetes and promoting a healthy weight; Diet can affect risk. o Blood lipid levels: Low risk: Cholesterol < 200 mg/100 ml; LDL cholesterol: <100 mg/100 ml; HDL cholesterol >60 mg/100 ml; Triglycerides: <150 mg/100 ml • Diet and heart disease risk : risk is affected by individual nutrients and whole foods o Increase risk: high sodium and saturated fat; diets high in red meat o Decrease risk: high in fiber, B vitamins; consuming fish, nuts and whole grains; fruits and vegetables o Reduced risk: Mediterranean diet: uses olive oil, typical diet is high in nuts, vegetables, and fruits; Fish is consumed routinely; red meat rar ely. Cancer • Second leading cause of death in the US • Lower risk: diet high in fruits and vegetables – rich in antioxidants; Mediterranean diet • Higher risk: diets high in fat, particularly animal fat Obesity • Excess intake of fat • Dietary fat is stored efficiently as body fat • Energy intake the exceeds expenditure Meeting Lipid Needs Fat and Cholesterol Recommendations • DRI: total fat intake of 20 -35% of calories for adults • AI for linoleic acid: 12 g for women and 17 g for men • AI for α -linolenic acid: 1.1 g for women and 1.6 g for men • Reduce saturated fat to less than 10 % of calories • Keep trans fat as low as possible • Limit sources of solid fat • Cholesterol: 2015 -2020 Dietary Guidelines do not set a limit on dietary cholesterol but still recommend eating as little as possible What a Scientist Sees : Are Eggs OK? - Think Critically o Why do you think the Dietary Guidelines removed the limit on dietary cholesterol but still recommend that people eat as little cholesterol as possible? Choosing Fats Wisely • Use of MyP late for menu planning • Analysis of the Nutrition Facts on the Food Label Role of Fat Replacers • Low fat or reduced fat dairy products: the total fat has been removed • Some reduced fat foods contain added sugars to improve tas te and texture • Some reduced fat foods contain soluble fiber or modified proteins to simulate fats; many of these are not absorbable