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Fats: Foods to Eat Concept 11 PowerPoint® Lecture Slide Presentation Created by Susan Tripp, MS, RD, LDN UMass Memorial Medical Center Copyright © 2011 Pearson Education, Inc. Pop Quiz True or False? 1. Americans today eat a lower percentage of their daily calories as fat than they did 50 years ago. ANSWER ANSWER 2. A healthy diet is very low in fat. 3. Only commercially made products, such as fried foods, baked goods, and snack items, contain ANSWER trans fats. 4. You can eat as many fat-free cookies as you want without gaining weight. ANSWER 5. Fat substitutes can be part of a healthy diet. ANSWER Copyright © 2011 Pearson Education, Inc. How Much (and What Types of) Fat Do You Need and What Are Its Food Sources? You Need to Consume Some Fat Daily What Are the Best Food Sources of Fats? Copyright © 2011 Pearson Education, Inc. How Much (and What Types of) Fat Do You Need and What Are Its Food Sources? We’ve learned so far: DO be sure to get enough of the two heart-healthy essential fatty acids, linoleic acid and alpha-linolenic acid, by eating plenty of polyunsaturated fats. DON’T worry about eating enough cholesterol, because your body makes all that it needs. DO choose mono- and polyunsaturated fats over saturated fats when possible, as they are better for you. DON’T add trans fats to your diet. Copyright © 2011 Pearson Education, Inc. How Much (and What Types of) Fat Do You Need and What Are Its Food Sources? The amount of fat in the American diet is at an all-time low of 33 percent of calories consumed. However, the total grams of fat consumed have increased by 4 percent since 1990 and total calories have increased by 10 percent. Americans are eating more of both fat and calories. Copyright © 2011 Pearson Education, Inc. You Need to Consume Some Fat Daily The AMDR recommendation is that 20 to 35 percent of your daily calories should come from fat. No more than 10 percent of your daily calories should come from saturated and trans fats. 5 to 10 percent of your total calories should come from linoleic acid. 0.6 to 1.2 percent of your total calories should come from alpha-linolenic acid. Healthy individuals are advised to limit dietary cholesterol to no more than 300 milligrams daily. Copyright © 2011 Pearson Education, Inc. Copyright © 2011 Pearson Education, Inc. Copyright © 2011 Pearson Education, Inc. What Are the Best Food Sources of Fats? Foods containing unsaturated fats are better for your health than foods high in saturated fat, cholesterol, and/or trans fats. Unsaturated fats are found in vegetable oils such as soybean, corn, and canola oils, as well as soybeans, walnuts, flaxseeds, and wheat germ. Plant oils are rich in unsaturated fatty acids. Copyright © 2011 Pearson Education, Inc. What Are the Best Food Sources of Fats? Most saturated fats come from animal foods such as fatty cuts of meat and whole-milk dairy products, and from tropical oils such as coconut, palm, and palm kernel oils. Extreme avoidance of fats and oils is unhealthy and can lead to the unnecessary elimination of certain foods. Copyright © 2011 Pearson Education, Inc. Where’s the Saturated Fat in Your Food? Figure 11.1 Copyright © 2011 Pearson Education, Inc. The Mediterranean Diet Refers to the dietary pattern found in areas of the Mediterranean region Researchers found that individuals from these areas had low rates of chronic diseases, such as heart disease and cancer, and a very long life expectancy. The diet was lower in food from animal sources, and higher in fat (mostly from olives and olive oil) and inexpensive grains, fruits, and vegetables. Intake of trans fats was negligible. The Mediterranean Diet Pyramid was designed to reflect these dietary patterns and lifestyle habits. Copyright © 2011 Pearson Education, Inc. Traditional Healthy Mediterranean Diet Pyramid Copyright © 2011 Pearson Education, Inc. What Is Trans Fat and Where Do You Find It? Trans Fats Are Found in Many Processed Foods Trans Fat Must Be Listed on Food Labels Copyright © 2011 Pearson Education, Inc. What Is Trans Fat and Where Do You Find It? Unsaturated fats found in oils are more susceptible to rancidity. Hydrogenation is a process that causes unsaturated fatty acids in oil to become more saturated and creates trans fats. Oil is heated and exposed to hydrogen gas. Typically, the hydrogens of double bonds are lined up on the same side of the carbon chain in a cis configuration. During hydrogenation, hydrogens may cross to the opposite side of the double bond, resulting in a trans configuration. Copyright © 2011 Pearson Education, Inc. Creating Trans Fatty Acids Figure 11.2 Copyright © 2011 Pearson Education, Inc. Trans Fats Are Found in Many Processed Foods Trans fats provide richer texture, longer shelf life, and better resistance to rancidity than do unsaturated fats. Increased use began in the 1980s when saturated fats were linked to heart disease. We now know that trans fats are actually worse for heart health than are saturated fats. Major sources are commercially prepared baked goods, margarine, fried potatoes, snacks, shortenings, and salad dressings. A small amount occur naturally in meat and dairy foods. It is not known if naturally occurring trans fats have the same negative effects on health as artificial trans fats. Copyright © 2011 Pearson Education, Inc. Trans Fats Must Be Listed on Food Labels In 2006, the FDA mandated that most foods must list grams of trans fats on the Nutrition Facts panel. The FDA estimates that trans fat labeling will save between $900 million and $1.8 billion annually in medical expenses, lost productivity, and pain and suffering. The labeling mandate caused many food producers to reformulate their product to eliminate the trans fat content. Copyright © 2011 Pearson Education, Inc. What Are Fat Substitutes and How Can They Be Part of a Healthy Diet? Fat Substitutes Can Be Carbohydrate-, Protein-, or Fat-Based Reduced-Fat Products Are Not Calorie Free Copyright © 2011 Pearson Education, Inc. What Are Fat Substitutes and How Can They Be Part of a Healthy Diet? Over 79 percent of adults in the United States regularly choose lower-fat foods and beverages. Throughout the 1990s manufacturers introduced more than 1,000 reduced-fat or low-fat products each year. Fat substitutes are designed to provide the creamy properties of fats for fewer calories and total fat grams. They can reduce calories from fat by over 50 percent without sacrificing taste and texture. Copyright © 2011 Pearson Education, Inc. Fat Substitutes Can Be Carbohydrate-, Protein-, or Fat-Based Most fat substitutes are carbohydrate based and use plant polysaccharides to retain moisture and provide a fatlike texture. Protein-based fat substitutes are created from the protein in eggs and milk. Fat-based substitutes are fats that have been modified to provide the physical attributes of fats for fewer calories or to interfere with the absorption of fat in the body. Example: mono- and diglycerides used as emulsifiers in baked good and icings. Same number of calories per gram as fat, but less is needed to provide the same effect. Copyright © 2011 Pearson Education, Inc. Fat Substitutes Can Be Carbohydrate-, Protein-, or Fat-Based Olestra (Olean) is created from a sucrose backbone with 6 to 8 long-chain fatty acids attached. The enzymes used in fat digestion cannot disconnect the fatty acids in olestra, so it is not absorbed in the digestive tract. Approved for use in 1996 in salty snacks such as chips Concern about its interference in the absorption of fatsoluble vitamins and carotenoids The FDA now mandates that fat-soluble vitamins be added to olestra to offset possible losses. Anecdotal reports of individuals experiencing cramps or diarrhea after eating olestra-containing products have not been verified by controlled research. Copyright © 2011 Pearson Education, Inc. Copyright © 2011 Pearson Education, Inc. Reduced-Fat Products Are Not Calorie Free Many reduced-fat products have close to the same number of calories as their regular counterparts. Products may have reduced fat, but increased carbohydrates, which adds back a significant number of calories. Ultimately, overconsuming calories leads to weight gain, regardless of whether a food is high or low in fat. Copyright © 2011 Pearson Education, Inc. Copyright © 2011 Pearson Education, Inc. The Top Five Points to Remember 1. Approximately 20 to 35 percent of your total calories should come from fat. Your intake of saturated fat should be no more than 10 percent of total calories. Your diet should contain no more than 300 mg of cholesterol daily. 2. Heart-healthy unsaturated fats are abundant in vegetable oils and nut oils. Soybeans, nuts, avocados, and flaxseeds are also rich in unsaturated fats. 3. Trans fatty acids are created by hydrogenating unsaturated fats. They are used in many processed foods. Your diet should be as low in trans fats as possible because they are harmful to your health. Copyright © 2011 Pearson Education, Inc. The Top Five Points to Remember 4. Fat substitutes are designed to provide all the properties of fats, but for fewer fat grams. Olestra is a fat substitute that is not absorbed by the gastrointestinal tract and thus contributes no calories. 5. Fat substitutes can reduce calories from fat in a food by more than 50 percent. However, many reduced-fat or fat-free products may have a similar number of calories as their traditional counterparts because carbohydrates have been added to the food. Copyright © 2011 Pearson Education, Inc. Answers to the Pop Quiz 1. TRUE. But because we’re eating more calories overall, our daily average consumption of fat grams is actually up. BACK TO QUIZ Copyright © 2011 Pearson Education, Inc. Answers to the Pop Quiz 2. FALSE. Whereas too much dietary fat may cause you to gain weight, eating too little isn’t healthy, either. A diet low in fat but high in added sugars may increase the level of fat in your blood. BACK TO QUIZ Copyright © 2011 Pearson Education, Inc. Answers to the Pop Quiz 3. FALSE. Although most trans fats are made from the hydrogenated oils that are found in commercially prepared, processed foods, trans fats also occur naturally in meat and dairy foods. BACK TO QUIZ Copyright © 2011 Pearson Education, Inc. Answers to the Pop Quiz 4. FALSE. Fat-free foods are not necessarily calorie free. BACK TO QUIZ Copyright © 2011 Pearson Education, Inc. Answers to the Pop Quiz 5. TRUE. Food containing fat substitutes can satisfy our taste buds while providing half the fat calories of regular versions of the same foods. BACK TO QUIZ Copyright © 2011 Pearson Education, Inc.