Sorting Out the Facts About Fat January 1995 Of all the nutrients in the food supply, fat and cholesterol probably receive the most attention from health professionals and the public alike. Preliminary results of lipid research continuously appear in professional journals and subsequently are reported in the media, thereby contradicting research previously reported. Yet, single studies rarely have an immediate impact on dietary recommendations, which are based on years of research and multiple studies with similar results. Fat and cholesterol can be complex and confusing topics. This issue of IFIC Review provides an in-depth look at this subject, including a review of fat, cholesterol and the technologies of hydrogenation and fat replacement. Fat - The Nutrient To many people, fat has negative health connotations. But as nutritionists know, fat is a vital nutrient. Like carbohydrates and protein, dietary fat is an important source of energy for the body. Fat is the most concentrated source of energy in the diet, providing nine calories per gram compared with four calories per gram from either carbohydrates or protein. Dietary fat supplies essential fatty acids, such as linoleic and linolenic acids, which are especially important to children for proper growth. Fat also is required for maintaining healthy skin, regulating cholesterol metabolism and as a precursor of prostaglandins, hormone-like substances that regulate many body processes. Dietary fat is needed to carry fat-soluble vitamins A, D, E and K and to aid in their absorption from the intestine. The body uses whatever fat it needs for energy, and the rest is stored in various fatty tissues. Some fat is found in blood plasma and other body cells, but the largest amount is stored in the body's adipose (fat) cells. These fat deposits not only store energy, but also are important in insulating the body and supporting and cushioning organs. What Is Fat? Technically, we should refer to "fats" in the plural, since there is no one type of "fat." Fats are composed mostly of the same three elements as carbohydrates -- carbon, hydrogen and oxygen. However, fats have relatively more carbon and hydrogen and less oxygen, thus supplying the higher fuel value of nine calories per gram. Fats are actually combinations of many different fatty acids, each exerting characteristic physiological and metabolic effects. These fatty acids are generally classified as saturated, monounsaturated or polyunsaturated. These terms refer to the number of hydrogen atoms attached to the carbon atoms of the fat molecule. One molecule of a fat can be broken down into three molecules of fatty acids and one of glycerol. Thus, fats are known chemically as triglycerides. Some common saturated fatty acids in foods include palmitic, stearic and myristic acids. A common monounsaturated fatty acid is oleic acid, and the most common polyunsaturated fatty acid in food is linoleic acid. Fats in foods are triglycerides containing both saturated and unsaturated fatty acids. In general, fats containing a majority of saturated fatty acids are solid at room temperature, although some solid vegetable shortenings are up to 75 percent unsaturated. Fats containing mostly unsaturated fatty acids are usually liquid at room temperature and are called oils. Fat is an important ingredient in many foods because of its functional properties. In many recipes, fat enhances the taste, aroma and texture of the food. Because it is digested more slowly than protein or carbohydrates, it also plays an important role in satiety, providing a sense of fullness after eating. Saturated fatty acids are more stable than unsaturated fatty acids because of their chemical structure. Stability is important in a cooking oil to prevent rancidity and off flavors or odors. Fats, Cholesterol and Coronary Heart Disease An excess of fat in the diet is recognized as one risk factor influencing the development of chronic disease. According to the Third National Health and Nutrition Examination Survey (NHANES III), conducted by the Center for Disease Control's National Center for Health Statistics and published in 1993, current average fat intake in the United States is about 34 percent of total calories, with approximately 12 percent of calories as saturated fat. Most health authorities advise that we reduce our fat consumption to 30 percent or less of total calories, with saturated fat providing 10 percent or less of total calories. It is not advised that children under the age of two be restricted in fat consumption. The main concern about excess saturated fat in the diet centers on its potential role in raising blood cholesterol. High blood cholesterol is a risk factor in the development of coronary heart disease (CHD). Cholesterol travels through the blood via particles called lipoproteins -- combinations of lipids and proteins. Too much cholesterol can build up in the blood and accumulate in the walls of the blood vessels, a condition known as atherosclerosis. This can ultimately reduce the flow of blood in major arteries, leading to heart attack. CHD kills more Americans every year than any other disease or group of diseases. Although the age-adjusted death rate for CHD has been reduced some 42 percent in the last 20 years or so, more than 500,000 people die annually as a result of heart attacks. High serum or blood cholesterol has been identified as one of the significant risk factors in the development of coronary heart disease. The diet we eat is just one factor influencing blood cholesterol levels. Many experts suspect that dietary influence on serum cholesterol may be more complex than just the cholesterol and fatty acid content of the diet alone. In past clinical trials, dietary habits, individual responsiveness, baseline serum cholesterol levels and other components of the diet have been identified as variables that can influence the effect of diet modification on blood cholesterol levels. In fact, for some people at risk, heredity is a stronger predictor of cholesterol levels than diet. Regardless of how little fat or cholesterol they eat, their bodies produce excess amounts of cholesterol that can spell trouble. Scientists may one day be able to identify a gene or phenotype that is carried by such "cholesterol responsive" individuals. Other risk factors beyond our control include age, race and gender. But there are many risk factors which we can influence. For example, in addition to reducing high blood cholesterol levels, we can reduce our risk of heart disease by avoiding cigarette smoking, controlling high blood pressure, maintaining healthy weight, getting adequate exercise and managing stress. For those with diabetes, controlling blood glucose levels also is important. Blood cholesterol reflects the amount of three major classes of lipoproteins: very-low-density lipoprotein (VLDL); low-density lipoprotein (LDL), which contains most of the cholesterol found in the blood; and high-density lipoprotein (HDL). LDL seems to be the culprit in CHD and is associated with cholesterol deposits on artery walls. In contrast, HDL is increasingly seen as more desirable. Recent studies indicate that the more HDL in the blood, the lower the risk of developing CHD. HDL apparently carries cholesterol out of the blood and back to the liver for breakdown and excretion. The average level of blood cholesterol in the U.S. adult population is approximately 210-215 milligrams/deciliter (mg/dl). The National Heart, Lung and Blood Institute's National Cholesterol Education Program classifies risk for heart disease based on total blood cholesterol levels as follows : The National Cholesterol Education Program (NCEP) recommends that individuals with cholesterol readings of 200 mg/dl and above -- about half of all Americans -- should have these readings confirmed by their physicians and follow-up on specific lipoprotein measurements. All adults over the age of 20 with desirable levels should have their blood cholesterol rechecked every five years. Dietary Management In June 1993 the NCEP released the Second Report of the Expert Panel on Detection, Evaluation and Treatment of High Blood Cholesterol (Adult Treatment Panel II). NCEP recommends dietary modification as the first treatment for elevated blood cholesterol. The recommendations are designed to reduce intake of saturated fat and cholesterol and to promote weight loss for those who are overweight. NCEP recommends limiting total fat to 30 percent of calories or less, saturated fat to 8-10 percent of total calories and cholesterol to less than 300 milligrams daily -- similar to the U.S. Dietary Guidelines. Controlling weight and increasing physical activity have also been added to the list of recommendations. If that approach fails to reduce blood cholesterol after a six-month trial, NCEP recommends a harder line. Saturated fat is further decreased to 7 percent of calories and cholesterol dropped to no more than 200 milligrams per day for another six months. If LDL levels cannot be reduced adequately through diet alone, drug therapy may be tried along with continued adherence to the diet. Fats and Cancer Numerous associations have been made between dietary fat and certain cancers, notably breast and colon. In 1989 the National Research Council (NRC) "Diet and Health" report pre-sented a series of dietary guidelines for reducing the risk of chronic diseases. While the recommendation to reduce dietary fat intake in order to prevent cancer was considered to be important, the scientific evidence to support this was unclear. According to the American Cancer Society (ACS) there is not enough data to quantify the exact number of fat grams that will reduce the risk of cancer. However, the U.S. Dietary Guidelines recommenda-tion to reduce fat intake to 30 percent or less of total calories is most prudent. Although a relationship between dietary fat and colon cancer still remains possible, the evidence is inconclusive. While research continues exploring the relationships between cancer and saturated, polyunsaturated and monounsaturated fats, the ACS advises consumers to moderate their total fat intake rather than emphasize one type of fat over another, and to increase fruit and vegetable consumption. Sources of Fats and Cholesterol The NRC 1988 Designing Foods report indicated that products from animal sources provide about 57 percent of the total fat and 75 percent of the saturated fat available in the diet. Primary animal sources of fat include red meats, poultry and fish; milk and milk products; and eggs. Fat from vegetable sources has increased in recent years, now accounting for about 43 percent of fat available in the diet. Vegetable fat is consumed mostly in the form of plant oils such as soybean, corn, sunflower, safflower, canola, cottonseed, palm and coconut. In addition to direct consumption of meat products, fat is consumed in fried foods and other products such as butter, margarine, dairy products, cheese, nuts, baked goods, salad oils, shortenings, mayonnaise, salad dressings, frostings, gravies and sauces. Cholesterol is not a fat, but rather a fat-like substance classified as a lipid. Cholesterol is vital to life and is found in all cell membranes. It is necessary for the production of bile acids and steroid hormones. Dietary cholesterol is found only in animal foods. Abundant in organ meats and eggs yolks, cholesterol is also contained in meats, chicken and shell fish. Vegetable oils and shortenings are cholesterol-free. Actually, most of the cholesterol in the blood is manufactured by the body, at a rate of about 800 to 1,500 milligrams a day, compared with 300 to 450 milligrams consumed daily by the average American in foods. Hydrogenated Fats Hydrogenation is the process of adding hydrogen molecules directly to a monounsaturated or polyunsaturated fatty acid. Hydrogenation is used to convert liquid oils to a semi-solid form for greater utility. For example, vegetable oils are often hydrogenated to produce shortenings or margarines. Hydrogenation also is used to increase the stability of a fat or oil, which is important in cooking and extending a product's shelf-life. All fats, particularly polyunsaturated fats, have a tendency to break down or oxidize when exposed to air. Oxidized fats impart an undesirable rancid flavor and odor. By adding hydrogen molecules, the fatty acids become more stable and resistant to oxidation. This is especially important for fats used in deep-fat frying. Hydrogenation also contributes important textural properties in food. The degree of hydrogenation can help influence the firmness and spreadability of margarines, flakiness of pie crust and the creaminess of puddings. Hydrogenation is not a novel food process, but in fact has been used since the turn of the century. In 1911, cottonseed oil was first hydrogenated in the United States to produce vegetable shortening as a replacement for lard. The manufacturing process became more popular in the 1930s with the development of margarine. Today, hydrogenation plays an important role in the stability and texture of various margarines, shortenings, baked goods, snack foods, cake mixes and a wide assortment of other foods. Extent of Hydrogenation Oils can be hydrogenated to a greater or lesser extent, depending on their desired uses in foods. Most oils used in foods, shortenings and institutional cooking are partially hydrogenated. Total hydrogenation of an oil is unsuitable for most food uses; when used, it comprises a very small portion of the total fat blend in a food. Hydrogenated oils are routinely used in place of fats with higher proportions of saturated fatty acids. For example, hydrogenation of soybean oil to produce margarine may raise its saturated fatty acid content from 15 percent to approximately 17 to 21 percent. But by comparison, butterfat is 53 percent saturated fat. Liquid vegetable oils can be lightly hydrogenated to improve stability and still remain highly unsaturated and in liquid form. Greater degrees of hydrogenation are used to make semisolid forms such as margarines and shortenings. Many of these products still contain a high percentage of unsaturated fatty acids. Some foods require a higher proportion of semi-solid fat. The flaky texture, taste, and mouthfeel of pie crust, for example, simply cannot be achieved when an unhydrogenated vegetable oil is used. Manufacturers use only the minimum degree of hydrogenation necessary to achieve the desired functional properties in food. Also, hydrogenation of oils rich in linoleic acid (a polyunsaturated fat) and oleic acid (a monounsaturated fat) results in the formation of oleic acid and stearic acid. Oleic acid has been found to have a neutral or possibly lowering effect on cholesterol levels. And unlike other saturated fatty acids, stearic acid does not appear to raise blood cholesterol levels. Innovations in Low-Fat Foods With fat contributing about 34 percent of total calories in the average diet, Americans have yet to meet dietary recommendations regarding fat. But with nutrition education and a variety of lower-fat food choices, consumers should be able to make progress in achieving dietary recommendations as noted in the USDA's Healthy People 2000 objectives. In fact, more choices of foods lower in fat are available in the supermarket today than ever before. Experts see that trend continuing with low-fat foods dominating new product introductions in the near future. The trend also is apparent in meats and dairy foods, which contribute the majority of fat and saturated fat in the American diet. Closer fat trimming by butchers has resulted in a 27 percent reduction in separable fat on retail cuts of beef, and the fat content of ground beef is 10 percent lower than 40 years ago, according to the National Research Council report, Designing Foods. Producers are cross-breeding to achieve leaner animals and also are using different grains, combinations of grains and/or other ingredients to lower the fat content of animals. In the dairy case, low-fat and skim milk now outsell whole milk, and choices abound in reduced-fat cheese, cottage cheese, sour cream, spreadable butter, margarine and yogurt. Sales of low-fat and fat-free products such as pastries, cookies, yogurt, salad dressing, processed cheese and frozen desserts are increasing rapidly. Some of these products have been developed by combining familiar ingredients such as milk and egg proteins, skim milk, water and/or a variety of carbohydrates in a process of heating, acidifying and blending to simulate the textural properties of fat and achieve the taste and sensory quality demands. Research in Fat Replacements With all these innovations, research and development continue to reveal various ingredients and processing methods to replace some or all of the fat in foods. Many companies are developing novel ingredients and combinations of commonly used food constituents as potential fat replacements. These ingredients can generally be classified as either calorie-reduced substitutes, which are digested normally, or calorie-free substitutes, which are virtually not absorbed by the body. Most current applications of fat reduction technology fall into the calorie-reduced category. These ingredients are digested normally, but because they are made from protein or carbohydrates plus water, they provide only one to four calories per gram compared with the nine calories per gram provided by fat. One of these fat replacers is Simplesse All-Natural Fat Substitute, a substance made from milk and egg- white protein, which was developed by the NutraSweet Company. Simplesse provides one to two calories per gram, compared with nine calories per gram from fat. A number of carbohydrate-based fat replacements are now being used in various food processing applications. These include ingredients made from tapioca dextrin, hydrolyzed corn starch and potato starch. The other broad category of fat replacers being developed includes calorie-free ingredients that virtually are not digested or absorbed. In this group, the best known is olestra, the generic name for an ingredient developed by the Procter & Gamble Company. Olestra is the first calorie-free fat substitute undergoing FDA review. Olestra is made from a combination of vegetable oils and sugar. Because of its structure, it is not broken down or digested by the body. Olestra's primary benefit as a fat replacement is that it performs the same functions as fat when used in frying, cooking and baking, yet contributes no fat or calories. Since olestra is predominantly fatty acids from common vegetable oils, its physical properties such as appearance, color, taste, heat stability and shelf life are comparable to conventional shortening or cooking oils. A food additive petition for olestra was submitted to the FDA in April 1987, and the agency is continuing its evaluation of the ingredient. If olestra receives FDA approval, initially it will be used as a substitute for fat used in commercial production of fried snack foods such as potato chips. Eventually olestra may be used to substitute a portion of the fat in oils and shortening used in the home, and to a greater extent in fats used for restaurant deep-fat frying. Other calorie-free fat replacements are under development and some are in the FDA review process. For example, "EPG," an ingredient developed by Arco Chemical Company, is made from fatty acids and could be used in cooking and frying. FDA Safety Review For all the benefits such fat replacements can bring, the overriding consideration is the absolute confidence that these ingredients are safe. FDA will continue to apply a rigid standard of review to ensure that confidence. Another very important consideration is the effect of fat replacements on overall dietary management. Clearly, fat substitutes have the potential to help Americans achieve national dietary goals to moderate fat consumption while satisfying their sensory preferences for rich and palatable foods. Research shows even the most motivated individuals have difficulty with long-term compliance to very low-fat diets, in part because they dislike the taste of some low-fat foods. Although fat substitutes will not compensate for poor dietary habits, these ingredients may be a help to many persons trying to eat healthful, balanced diets. Clearly, consumers have expressed a demand for foods lower in fat. As companies continue applying their research and development skills to this challenge, a number of innovative products are sure to follow. Conclusion Moderation in fat and cholesterol consumption is only one aspect of good nutrition. Variety, moderation and balance of all foods is the most prudent approach for the general population. Moreover, a well-balanced diet while getting plenty of exercise, maintaining proper weight, avoiding smoking and controlling diseases such as hypertension and diabetes is the best approach to a healthy lifestyle. FANSA Statement on Trans Fatty Acids June 1994 The Food and Nutrition Science Alliance (FANSA) is a partnership of four leading diet and health organizations: The American Dietetic Association, the American Institute of Nutrition, the American Society for Clinical Nutrition, Inc. and the Institute of Food Technologists. Collectively, their membership totals more than 96,000 food and nutrition professionals. Introduction Trans fatty acids occur naturally in beef, butter, milk and lamb fats and in commercially prepared, partially hydrogenated margarines and solid cooking fats. Partially hydrogenated vegetable oils were developed in part to help displace highly saturated animal and vegetable fats used in frying, baking and spreads. Their use in margarines probably provides a more healthful alternative to butter, beef tallow, and lard because they have less saturates. The main sources of trans fatty acids in the American diet today are stick margarine, shortening, commercial frying fats, and high fat baked goods. Some clinical studies show that at high levels of intake, trans fatty acids may raise blood levels of LDL cholesterol, the so-called "bad" cholesterol, much like saturated fatty acids do, only less markedly. In addition, some studies have shown that trans fatty acids, again at high levels of intake, modestly lower HDL levels, the "good" cholesterol. However, at levels of intake typical in the American diet, trans fatty acids do not reduce HDL cholesterol. New developments in fat substitutes coupled with Americans' demand for low-fat and fat-free foods and a gradually diminishing consumption of all fats will likely keep overall consumption of trans fatty acids in the current range, if not reduce intake. Therefore, current dietary advice to reduce consumption of saturated fatty acids far outweighs any cause for alarm about trans fatty acids in foods. Fat Consumption: The Big Picture Americans consume a lot of fat -- averaging 34-36 percent of a person's daily energy intake. Current health recommendations call for a diet consisting of no more than 30 percent of calories from fat. Reducing total fat intake also lowers intake of saturated and trans fatty acids. Fat is a complex mixture of dozens of different fatty acids from animal and vegetable foods. Fatty acids can be grouped according to their chemical structure into three categories: saturated, monounsaturated and polyunsaturated. Consuming abundant saturated fatty acids raises blood cholesterol levels and increases the risk of heart disease. We consume about 12-14 percent of our total energy from saturated fatty acids but only about 2-4 percent from trans fatty acids. Health officials recommend reducing intake of saturates to less than 10 percent of total energy. Saturated fatty acids predominate in animal fats such as beef and lamb fat, butter, cheese and tropical oils. Cutting saturated fat consumption essentially means limiting how much of these foods we eat. Trans fatty acids are produced during the hydrogenation of vegetable oils, a process that adds hydrogen to unsaturated fatty acids in vegetable oils and changes the fat from a liquid to a soft or solid state. Partially hydrogenated vegetable oils can replace naturally solid, saturate-rich fats, such as lard and beef tallow, in margarines and baked foods as well as in commercial frying, where vegetable oils cannot be used. Margarines in the U.S. contain anywhere from 0-30 percent trans fatty acids; stick margarines contain more trans fatty acids than soft tub margarines and spreads. Avoiding high intakes of trans fatty acids means limiting consumption of commercially fried foods, stick margarines and shortening, and high fat baked foods. This is the same strategy health educators advise for limiting total fat intake. The European Difference In Europe, both vegetable and marine oils may be hydrogenated and used in margarines. Some European margarines do not contain partially hydrogenated oils. Instead, they combine liquid vegetable oil with more saturated fats such as lard, beef tallow and tropical oils to produce different margarines. Thus, these margarines, while free of trans fatty acids, contain saturates instead, plus some cholesterol. Fat Intake and Health Consequences How much trans fatty acids do Americans consume? Estimates vary from about 8 to 13 grams/person/day, or about 2-4 percent of total energy. This compares with 12-14 percent total energy from saturated fatty acids. Trans fatty acids, like saturated fatty acids, may raise blood LDL cholesterol levels (the so-called "bad" cholesterol) but not as much as saturates do. At high levels of intake--twice the amount currently consumed--they also modestly reduce HDL levels, the so-called "good" cholesterol. There is little evidence to suggest that current levels of consumption of trans fatty acids are harmful. In the Netherlands, where consumption of trans fatty acids may be twice that in the U.S., no adverse effects on heart disease have been attributed to these substances. Dutch researchers and others in the U.S. and Australia have shown that trans fatty acids have far more moderate effects on blood cholesterol levels than saturated fatty acids. A recent USDA study has shown that in healthy persons a diet containing trans fatty acids in amounts currently consumed did not lower HDL levels. Consuming twice the level of trans fatty acids reduced HDL levels only 2.8 percent. Existing data are insufficient to assess the overall impact of trans fatty acids on health, especially at levels currently consumed. Nutrition scientists agree, however, that the most important dietary consideration for Americans is to reduce fat intake in general and saturated fatty acid consumption in particular, especially for persons at high risk of heart disease. Mortality from heart disease has declined in the U.S. over the past twenty years, partly because of the shift away from more saturated animal fats to more unsaturated vegetable oils. Unlike animal fats, vegetable fats and oils have the additional advantages of containing no cholesterol, providing useful amounts of the essential fatty acid, linoleic acid, and containing the antioxidant, vitamin E. Consumption of margarine has been a significant factor in achieving the shift away from the more saturated animal fats. The development of partially hydrogenated vegetable fats and oils has not only enabled consumers to decrease their intake of more saturated animal fats, it has permitted the replacement of saturate-rich frying and baking fats with less saturated vegetable fats. Pure vegetable oils would be unsuitable for these purposes because of the ready formation of oxidation products during frying and the inability of liquid oils to fully substitute for solid fats in baked foods. Thus, partially hydrogenated vegetable oils have permitted a decrease in consumption of saturated fatty acids along with the reformulation of commercially baked goods. Conclusion There is much we do not know yet about the metabolism of trans fatty acids and what range of intake might be considered a health risk. What the science tells us so far is that trans fatty acids resemble saturated fatty acids in some, but not all ways and that the need to reduce consumption of saturated fatty acids far outweighs any cause for alarm about trans fatty acids in foods. Role of Saturated Fatty Acids Fine-Tuned Ancel Keys and Mark Hegsted, pioneers in fat research, were among the first to suspect it. Others have confirmed it. All saturated fatty acids are not equal in their cholesterol-raising effects. Nearly 40 years ago, researchers first noticed the different effects of saturated and polyunsaturated fats on serum cholesterol. In the early 1950s, scientists observed that diets rich in unsaturated vegetable fat resulted in lower levels of serum cholesterol than diets rich in the more saturated animal fats. Keys and Hegsted each developed equations to predict the effect of dietary modifications on serum cholesterol. Each equation showed that saturated fat significantly raised cholesterol levels. But both researchers found that fats rich in stearic acid (C18) did not fit the predictive equation. Additionally, Hegsted's formula indicated that saturated fatty acids with shorter carbon chains (C6-C12) were not cholesterol-raising and that myristic acid (C14) was the most hypercholes-terolemic of the saturated fatty acids. Keys' calculations, on the other hand, identified palmitic (C16) as the most potent saturate. Over the next 25 years, other researchers confirmed the neutral effect of stearic acid on blood cholesterol levels in animal and human studies. As a result, The National Research Council's report Diet and Health and The Surgeon General's Report on Nutrition and Health noted the neutral effect of stearic acid on cholesterol. In light of the findings about stearic acid, some researchers recommend no longer grouping it with other saturated fatty acids. Beef and cocoa butter have a high stearic acid content. Decisions on Labeling In recently-revised food label regulations, both FDA and USDA define saturated fat strictly by chemical composition, as "the sum of all fatty acids containing no double bonds." Regulators in Canada and the European Community similarly define saturates by chemical composition. Despite convincing evidence on stearic's effects, the federal government continues to include it in the definition of saturated fat for labeling purposes. In recognition of the neutral effects of stearic acids, USDA allows the voluntary label declaration of stearic acid as a subcomponent of saturated fat. Although the evidence about stearic acid is strong, the effects of other saturated fatty acids, such as lauric, myristic and palmitic acids, are still under investigation. Some research indicates that there is a difference among these saturated fatty acids on blood lipids. Confounding variables have led researchers to question effects beyond fatty acid content which influence effects on serum cholesterol. The relationship between saturated fatty acids and other dietary components, such as protein or fiber, appears more complicated than previously supposed. Practical Applications The results of fatty acid research are likely to have practical application for food scientists. Changing the fatty acid profile of oils is a likely beginning. In fact, some companies are developing genetically engineered canola plants to produce an oil with increased levels of stearic acid for use in margarine and confectionary production. Some researchers see the structure of individual triglycerides, as opposed to the fatty acid composition of an oil, as the next frontier. Every triglyceride, or fat, contains three fatty acids. The rearrangement of these three fatty acids within a triglyceride molecule potentially could effect the athrogenic potential of such a fat. Scientists continue to search for the best dietary fatty acid profile for disease prevention. References 1) Food and Nutrition Science Alliance (FANSA). "Statement on Trans Fatty Acids." Journal of The American Dietetic Association 94:1098-1100, 1994. 2) Hunter, J. E. and Applewhite, T. H. "Reassessment of Trans Fatty Acid Availability in the U.S. Diet." American Journal of Clinical Nutrition 54:363-9, 1991. 3) International Life Sciences Institute, Nutrition Foundation. Present Knowledge in Nutrition, Sixth Edition. Washington, D.C. ILSI, NF, 1990. 4) Judd, J.T. et al. "Dietary Trans Fatty Acids: Effects on Plasma Lipids and Lipoproteins of Healthy Men and Women." American Journal of Clinical Nutrition 59: 861-7, 1994. 5) Mensink, R. and Katan, M. "Effect of Dietary Trans Fatty Acids on High-Density and Low-Density Lipoprotein Cholesterol Levels in Healthy Subjects." New England Journal of Medicine 323:439-445, 1990. 6) National Cholesterol Education Program. "Second Report of the Expert Panel on Detection, Evaluation and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel II)." Journal of the American Medical Association 369:3009-14, 1993. 7) National Center for Health Statistics, Centers for Disease Control and Prevention, "National Health and Nutrition Examination Survey (NHANES III)." Journal of the American Medical Association 369:3002-08, 1993. 8) National Research Council. Designing Foods. Washington, D.C.: National Academy Press, 1989. 9) U.S. Department of Health and Human Services. The Surgeon General's Report on Nutrition and Health (DHHS/PHS Publication No. 88-50210). Washington, D.C.: U.S. Government Printing Office, 1988. 10) U.S. Departments of Agriculture and Health and Human Services. Healthy People 2000: National Health Promotion and Disease Prevention Objectives for the Nation. Washington, D.C. Public Health Service, 1991. 11) U.S. Departments of Agriculture and Health and Human Services. Nutrition and Your Health: Dietary Guidelines for Americans, Third Edition (Home and Garden Bulletin No. 232). Washington, D.C.: U.S. Government Printing Office, 1990. 12) Willett, W.C., et al. "Intake of Trans Fatty Acids and Risk of Coronary Heart Disease Among Women." Lancet 341:581-5, 1993. Reprinted from the International Food Information Council Foundation, 1995

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