(FDA) now requires information about trans-fat content of foods on nutrition food labels. These new labels are scheduled to go into effect on January

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1 Produced by Nadine J. Kirkpatrick, BS Doctoral Student Cristy Hathaway, BS, Research Assistant Sheri Zidenberg-Cherr, PhD Nutrition Science Specialist Cooperative Extension Department of Nutrition University of California Davis, CA April 2004 In 2001, Americans consumed almost 36 percent of their calories from restaurants, takeout, or other places away from home. This trend, as well as the desire for comfort and convenience contributes to the over consumption of fat by Americans. At restaurants, for example, patrons are not able to control how much fat is in the meals that are prepared by the chefs and portion sizes are larger. In supermarkets, many customers are tempted to purchase prepared meals that only require heating and tend to ignore the fat content of the foods (1). This can result in weight gain and obesity. Although there are health concerns with eating a diet that is high in fat, it is important to realize that fat is an essential nutrient, meaning that like all nutrients, it is beneficial in appropriate quantities. What are fats? In order to understand the functions of fat, as well as the concerns associated with consuming a diet high in fat, it is important to understand its composition (2). Fats are a subset of a class of nutrients called lipids, which also include phospholipids and sterols. Usually when people refer to fats and oils, they are speaking of triglycerides, the most common forms of fat in the diet. Triglycerides come in many sizes and several varieties, but they all share a common structure: all have a backbone of glycerol to which three fatty acids are attached. While all glycerol molecules are alike, the fatty acids may vary in two ways: length and degree of saturation (2). What are fatty acids? There are three types of fatty acids, which are the basic chemical units in fat: saturated, monounsaturated, and polyunsaturated. All dietary triglycerides are made up of a mixture of these fatty acid types (2). Saturated fatty acids are found in the largest amounts in fats from meat and dairy products and in some vegetable fats such as coconut, palm, and palm kernel oils. They are usually solid at room temperature (2). Monounsaturated fatty acids are found mainly in olive, peanut, and canola oils. They are liquid at room temperature (2). Polyunsaturated fatty acids are found mainly in safflower, sunflower, corn, soybean, and cottonseed oils and some fish. They are usually liquid at room temperature (2). What are trans-fatty acids? Trans-fatty acids are the product of hydrogenating oils, a process which converts liquid fat (vegetable oils) to solid fat (margarine). This method has been used by many food manufacturers because it extends the shelf life of foods, increases resistance to rancidity and is fairly inexpensive (3). On average, about 3 percent of total calorie intake in the United States can be attributed to trans-fats (3,4). Studies have found that trans-fats raise LDL-cholesterol and total cholesterol, as do saturated fats; other findings of studies suggest a correlation of cardiovascular disease and trans-fat intake (3,5). Since there is concern about the rising evidence of this correlation, the Food and Drug Administration 1

2 (FDA) now requires information about trans-fat content of foods on nutrition food labels. These new labels are scheduled to go into effect on January 1, In order to avoid foods high in trans-fats there is a new food processing method called low-trans hydrogenation which is more expensive than regular hydrogenation but would yield a significantly lower percentage of trans-fatty acids in food products and therefore seems to represent a possible alternative to the conventional method (5). What functions do fats serve? Fat can be found in various forms in the diet and each form can serve a different purpose (2). Essential fatty acids (EFA) are omega-3 and omega-6 fatty acids that the human body is not able to create, and must come from food source. Alpha-linolenic acid (omega 3) and linoleic acid (omega 6) are the two essential fatty acids; they play a key role in the immune system, vision, and cell structure. Good food sources for these essential fatty acids include vegetables oils that can be found in mayonnaise or salad dressings. While uncommon in the US where fat is abundant, a deficiency in essential fatty acids can result in diarrhea, anemia and skin problems. Another omega 3 fatty acid, which is not one of the EFAs, is eicosapentaenoic acid. Eicosapentaenoic acid is abundant in fish such as salmon, halibut, and trout. Triglycerides are mainly responsible for energy storage and the insulation of the body and its organs. They also transport the fat-soluble vitamins and contribute to taste and feeling full after eating a meal (2). Above all, fat supplies energy needed for physical activity. (2). How much fat should be included in your diet? The US Dietary Guidelines recommend limiting total fat to less than 30 percent of total calories, and of that, limit saturated fat to 10 percent of total calories. For total fat, this translates into approximately 53 grams of total fat with 16 grams saturated fat in a 1600-calorie diet, 73 grams of total fat with 22 grams of saturated fat in a 2,200 calorie diet, and 93 grams of total fat with 28 grams saturated fat in a 2800 calorie diet (2). According to the new Institute of Medicine Food and Nutrition Board report on Acceptable Macronutrient Distribution Range for fat, it is suggested to maintain a total dietary fat intake of 20 to 35 percent for adults, 30 to 40 percent for children ages 1 to 3, and 25 to 35 percent for children ages 4 to 18 (6). When too much fat becomes a problem: Fat and Obesity There has been a substantial rise in the prevalence of obesity among children and adults in the United States. This contributes to the population being at risk of developing diabetes, high blood pressure as well as cardiovascular disease (7). The main environmental or lifestyle factors contributing to obesity are overeating and choosing a high calorie diet in combination with inadequate exercise (8). Choosing supersized or large portions may lead to overeating. National statistics show that more than 20 percent of children are considered overweight or are susceptible to developing obesity (9). Fat and Cardiovascular Disease (CVD) While it is essential that the diet include some fat, most health authorities recommend that reducing intake of fat, saturated fat, and cholesterol, may reduce the risk for heart disease. The way diet affects blood cholesterol varies among individuals. However, blood cholesterol does increase in most people when they eat a diet high in saturated fat. For adults, a desirable level of blood cholesterol is 200 mg/dl or below. As blood cholesterol increases above this level, greater risk for heart disease occurs. CVD risk can also be increased by having high blood pressure, diabetes, a family history of premature heart disease, being obese, being male, and smoking cigarettes (2). Many studies have found that the rate of CVD is very low among individuals and societies who consume large amounts of fish (10). Studies on indigenous Alaskans and Japanese populations, for instance, have shown that fish may significantly decrease the possibility of atherosclerosis. In various studies, omega-3-fatty acids (eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]) in fish have been associated with lowering the risk for CVD and mortality. Saturated and transfats, on the other hand, have been shown to elevate the risk for CVD (11). It is important to point out that not all fat is bad or harmful. There is a risk when consuming high amounts of saturated fat, but foods with omega 3 fatty acids can be beneficial (10,11). 2

Fat and Cancer There is evidence that diets high in total fat or saturated fatty acids are associated with a higher risk of several cancers, especially of the colon, prostate, and breast.

3 Fat and Cancer There is evidence that diets high in total fat or saturated fatty acids are associated with a higher risk of several cancers, especially of the colon, prostate, and breast. Given the present recommendations to reduce total fat and saturated fatty acids, many people may go to extremes and try to include only polyunsaturated fatty acids in their diet. The effects of following such a diet are unknown. The preparation of meats is also of importance. Deep-frying foods or charbroiling them until they have a burned surface may pose a risk to the consumer since this process results in fat oxidization which has been shown to increase the risk for developing cancer (12). Thus, the best advice is dietary moderation. How can fat intake be calculated? You can determine the number of grams of fat that provide 30 percent of calories in the daily diet as follows: A. Multiply the total calories for one day by 0.30 to get the recommended amount of calories from fat per day. Example: 1,800 calories x 0.30 = 540 calories from fat. So if you consume 1,800 calories per day, about 540 calories should come from fat. B. Divide calories from fat per day by 9 (each gram of fat contains 9 calories) to get grams of fat recommended per day. Example: 540 calories from fat divided by 9 = 60 grams of fat. Dietary suggestions to control fat intake According to the American Heart Association, consumers should limit their intake of foods rich in saturated fats, including tropical oils such as palm and coconut oil (13). Here are a few simple suggestions to accomplish this goal: Consume at least five servings of fruits and vegetables each day to partially replace fatty foods. Add a mixture of grain products to the diet. Replace fatty meats with skinless chicken, fish, or other lean meats, and drink fat-free or low-fat milk instead of whole milk. What are some food sources for different kinds of fat? Saturated Fats Meat, poultry, whole-dairy products, coconut and palm oils (11) Monounsaturated Fats Olive & canola oil, peanuts, and avocados (11) Polyunsaturated Fats Safflower, sunflower, corn, and soybean-oil, as well as fish (omega 3) (11) Trans-fatty acids Bakery products, crackers, chips, dairy and meat products (3,4,5) Omega 3 and Omega 6 Fatty acids Fish such as salmon and trout, salad dressings, and vegetable oils (2) Olestra, a fat substitute Olestra is a non-caloric fat substitute found in some low-calorie snack foods such as potato chips; therefore, products made with olestra are much lower in calorie content than ones made with regular fat (14). There was concern that consuming high amounts of olestra would result in intestinal problems that could reduce the absorption of the fat-soluble vitamins (A, D, E, and K), but current research has shown that the consumption of olestra does not cause intestinal problems or affect serum levels of fat-soluble vitamins. One potential problem with the introduction of fat-replacement products is over-consumption since these products are considered fat free. For example, instead of eating fifteen regular potato chips, consumers may eat thirty olestra potato chips. Since fat substitute products still have calories, which is commonly misconceived, the consumption of a similar amount of calories or even more calories may be the result (14). 3

4 Table of Common Foods Containing Cholesterol, Total Fat, and/or Saturated Fat (15): Cholesterol Total fat Saturated fat mg g g Meat, Poultry, Fish, and Eggs Prime rib, 3 oz Beef liver, braised, 3 oz Lean cut (eye of round), 3 oz Lean and fat Lean only Ground beef, cooked, 3 oz patty Regular (75 percent lean & 25 percent fat) Extra lean (95 percent lean & percent fat) Chicken, light and dark meat, roasted With skin (178g) Without skin (146g) Tuna, canned, 3 oz In oil In water Shrimp, steamed 4 large Eggs, large, cooked, 1 Yolk White Dairy Products Milk, 1 cup 3.25 percent fat percent fat percent fat Skim (Nonfat) Yogurt, 1 cup Nonfat plain Low-fat, plain Low-fat, fruit flavored Fats, Oils, Sweets Butter, 1 tbsp Margarine, 1 tsp Mayonnaise (regular), 1 tbsp Sour cream, 1 tbsp Cream cheese, 1 tbsp Cheesecake (9 in), 1/12 (99g) No Bake

5 References: 1 [Online source]: Tips of the Month; April 2001; Diet and Health Trends Part II. 2001; DiscoverFitness.com; 2 Wardlaw GM. Contemporary nutrition: Issues and Insights. 2003; McGraw-Hill: New York. 3 Questions/Answers on Trans Fatty Acids. J Am Diet Assn; 2001; 101(8); p Stahl P. What's new at the FDA - Informing consumers about trans fat labeling. J Am Diet Assn; 2000; 100(10); pp. 1132,1134, Dausch JG. Trans-fatty acids: A regulatory update. J Am Diet Assn; 2002; 102(1); pp. 18,20. 6 Institute of Medicine, Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (Macronutrients); 2002; National Academy Press; 7 Barlow SE et al. Treatment of child and adolescent obesity: Reports from pediatricians, pediatric nurse practitioners, and registered dietitians. Pediatrics; 2002; 110(1 SUPPS); pp Dube MG, et al., Central leptin gene therapy blocks high-fat diet-induced weight gain, hyperleptinemia, and hyperinsulinemia - Increase in serum ghrelin levels. Diabetes; 2002; 51(6); pp Ogden CL, Flegal KM, Carroll MD, Johnson CL. Prevalence and trends in overweight among US children and adolescents, JAMA. 2002;288: Hu FB, et al., Fish and omega-3 fatty acid intake and risk of coronary heart disease in women. J Am Med Assn; 2002; 287(14); pp [Online source]: Medial Encyclopedia - Fat. 2001; MEDLINEplus. 12 Tareke E, Rydberg P, Karlsson P, Eriksson S, Tornqvist M. Analysis of acrylamide, a carcinogen formed in heated foodstuffs. J Agric Food Chem, 2002 Aug 14;50(17): [Online Source]: ; American Heart Association. 14 Patterson RE, et al. Changes in diet, weight, and serum lipid levels associated with olestra consumption. Arch Intern Med; 2000; 160(17); pp [Online Source]: ; USDA: NUTRIENT DATA LABORATORY FOR MORE INFORMATION You ll find detailed information on many aspects of health and nutrition in other publications, slide sets, CD-ROMs, and videos from UC ANR. To order these products, visit our online 5

6 catalog at You can also place orders by mail, phone, or FAX, or request a printed catalog from University of California Agriculture and Natural Resources Communication Services 6701 San Pablo Avenue, 2nd Floor Oakland, California Telephone: (800) or (510) , FAX: (510) inquiries: danrcs@ucdavis.edu An electronic version of this publication is available on the ANR Communication Services Web site at Publication by the Regents of the University of California Division of Agriculture and Natural Resources All rights reserved No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the written permission of the publisher and the authors. To simplify information, trade names of products have been used. No endorsement of named products is intended, nor is criticism implied of similar products that are not mentioned. The University of California, in accordance with applicable Federal and State law and University policy, does not discriminate on the basis of race, color, national origin, religion, sex, disability, age, medical condition (cancer-related), ancestry, marital status, citizenship, sexual orientation, or status as a Vietnam-era veteran or special disabled veteran. The University also prohibits sexual harassment. Inquiries regarding the University s nondiscrimination policies may be directed to the Affirmative Action Director, University of California, Agriculture and Natural Resources, 300 Lakeside Drive, 6th Floor, Oakland, CA (510) For information about obtaining this publication, call (800) For downloading information, call (530) pr-11/05 This publication has been anonymously peer reviewed for technical accuracy by University of California scientists and other qualified professionals. The review process was managed by the ANR Associate Editor for Food and Nutrition. 6

'Eat Smart' - Nutrition for a Healthy Heart

'Eat Smart' - Nutrition for a Healthy Heart Definitions - Fats & Cholesterol Found in Blood LDL HDL 'low density lipoprotein' also known as 'bad cholesterol' major cholesterol-carrying molecule in blood delivers cholesterol to the arterial walls