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Can Trans Fat Ever Be Positive?
There is a small amount of trans fat that occurs naturally in some foods, such as in beef, lamb and dairy. However, it is quite different and not considered a health risk like the artificially produced trans fats from partially hydrogenated oils. Research has shown that some of these naturally occurring trans fats, such as conjugated linoleic acid, (CLA) have positive health benefits. This may be a confusing point, so the easiest way to distinguish between the two types is that one is naturally-occurring and the other is the result of a manufactured hydrogenating process. The trans fats that concern health experts are the those from partially hydrogenated oils.
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What are the Health Effects of Trans Fats?
In the last few years, compelling scientific data proves the negative health effects of hydrogenated / trans fats, especially for coronary heart disease. The literature finds that they not only exert the same effects of a saturated fat for the development of heart disease, but that they have an even more profound effect. Trans fats raise serum cholesterol, low density lipoproteins (bad cholesterol), lipoprotein a, and triglycerides while also decreasing the level of high density lipoproteins (good cholesterol). In addition, trans fats may also contribute to the development of Syndrome X, a group of risk factors ranging from hypertension, obesity, and elevated blood lipids, to type II diabetes. Trans fats are aggressive for promoting clot formation in blood vessels of the heart, brain, and other parts of the body. As the intake and production of trans fats have increased in the United States, so has the increase in the rate of heart disease.
Stronger evidence for the association of trans fats and heart disease comes from the conclusions of the Nurses Health Study led by Harvard and The Brigham and Women's Hospital. Women who ate the most trans fats were 50 percent more likely to develop heart disease over a fourteen year period than those who ate the least. Women with the lowest intake of trans fats and the highest intake of polyunsaturated fats were 70 percent less likely to develop heart disease when compared with women who ate the most trans fats and the least polyunsaturated fats. Researchers at Harvard School of Public Health estimate that the replacement of 2% of energy from trans fats with energy from non-hydrogenated, unsaturated fats would decrease risk of coronary heart disease by 53%.
How much trans fat is
in the foods we eat? |
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| French Fries (medium sized order) |
6-14 grams |
| Fried Chicken Dinner |
7 grams |
| Fried Dutch Apple Pie (Fast Food) |
2 grams |
| Frozen Apple Pie, one slice |
4 grams |
| Donuts, one |
5 grams |
| Cream Filled Cookies, one serving |
2 grams |
| Pound Cake, one slice |
4 grams |
| Chicken Nuggets, 5 |
4 grams |
| Potato Chips, small bag |
3 grams |
Approximately 80 percent of the trans fat in the American diet comes from partially hydrogenated oils used in many fried foods and snack foods. To date, there is no daily value for the dietary intake of trans fat. The 2005 US Dietary Guidelines Committee is recommending that Americans keep their trans fat intake to as low as possible. Tommy Thompson, the Secretary of HHS, said at a news conference of the Dietary Guidelines, January 2005, that the FDA may recommend that daily intake of trans fat be less than 2 grams per day, perhaps less than 1 gram per day. This is a very low amount when one considers how much trans fat is in the products we eat every day. The table below lists some examples. The National Academies of Sciences Institute of Medicine (NAS/IOM) also recommends eating as little hydrogenated oil as possible. According to data compiled by the FDA, removing trans fats from the food supply would prevent between 11,000 and 30,000 premature deaths and billions of dollars in medical costs per year. Consumers will be reading these labels more carefully and basing their decision on the information provided.
Harmful Effects of Trans Fats for
Cardiovascular Disease. |
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| Raise LDL (low density lipoproteins, bad cholesterol) and Lipoprotein (a) |
| Elevate levels of triglycerides in the blood |
| Lower levels of HDL (high density lipoproteins, good cholesterol) |
| Increase blood clotting properties to make blood platelets more likely to clot inside blood vessels, brain, and elsewhere. |
| Trans fats increase inflammation, a condition which may lead to an increased risk of heart disease, and diabetes |
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| TOP |
Trans Fats
by Connie Guttersen, RD PhD,
author of the Sonoma Diet
The Battle Over Fat.
The dietary guidelines introduced this year by the government are designed to help consumers understand that dietary fat is not all the same. The good news, judging from the survey results of a recent California Olive Industry survey, is that consumers are actually getting that message.
 As the new labeling requirements, which require manufacturers to list trans fats, are implemented, consumers will have even more opportunity to educate themselves about dietary fats. Many manufacturers have already added trans fats to their packaging, and all will be required to do so by January 2006.
This will be a big job, as it is estimated that 40% of the food at the grocery store--including some products regarded as healthy--contain partially hydrogenated trans fats.
TOP
The History of Hydrogenation.
The hydrogenation process became popular in the 1960s when it provided an alternative to frying and baking with saturated fat. Hydrogenated oils extended the shelf life and stability of the food, provided the same desirable characteristics in food without providing dietary cholesterol, and appeared to be the healthier alternative to saturated fat. Consumption rose significantly in the 1980s and 1990s when the public embraced the connection between heart disease and saturated fats. Fast food restaurants replaced the beef fat in the fryers with partially hydrogenated oils. Food manufacturers began to market their products as free of saturated fats and cholesterol--but unfortunately, the substitute was partially hydrogenated oils. TOP
Mistaken Beliefs on Health Attributes.
In the beginning, manufacturers also thought that hydrogenation was a better solution from a health perspective. It was believed to address the dietary and health concerns of highly saturated tropical oils (coconut and palm oil) as well as other saturated fats typically used for frying in the industry. Unfortunately, this was done with the misconception that hydrogenated oils offered the same protective effects against heart disease as naturally occurring plant oils and were therefore a healthier option. These days, of course, we know this is wrong.
Nutritionists and medical researchers confirm that the artificially produced fat is the most dangerous fat in the food supply, increasing bad cholesterol levels faster than saturated fat and interfering with the body’s metabolic process. TOP
Why It's Hard to Wean Off Hydrogenated Oils.
Hydrogenated vegetable oils can be used in place of butter or lard in baking, and will yield similar desirable baking properties of these fats. Hydrogenation is what gives margarine its creamy consistency, or pie crusts their flaky tender textures. The fact that it prolongs the shelf life and stability of many baked goods is also an important factor.
In addition, during high temperature cooking, hydrogenated oils are far more stable and have a higher smoke point than most cooking oils. From the perspective of the food industry, it is important to understand their product reformulating challenges, in that the health promoting benefits of a fat or oil may not always have the same ability to grant a desirable flavor and texture in food during high temperature cooking.
When looking for a replacement, the choice of oil to use in frying is difficult, since factors such as stability, price, and nutrition must be considered. An alternative oil must give the foods the taste, texture, and shelf life consumers have come to expect. Oils with a saturated fatty acid profile may be stable but they offer less nutritional benefits and increase the risk of heart disease. Hydrogenated fats, while stable in frying, are not warranted due to their high trans fatty acid content and negative health effects. Soybean oil, due to its high content of PUFA, is considered to be superior to hydrogenated fats from a nutritional standpoint. However, it is inferior in thermal and oxidative stability. TOP
Sourcing New Oils.
Today, a new breed of oils is emerging. New margarines are being marketed as trans fat free, oil processors are mixing super hard, trans free hydrogenated oils with liquid oils to make a suitable replacement. Canola, as well as sunflower oils, which remain stable at high temperatures, are coming out in the market. Fully hydrogenating an oil--a process that changes the chemical composition of the vegetable oil by using heat and a catalyst-- eliminates trans fat but makes a fat so hard that it is impossible to cook with and must be blended with an oil. This product is called "fully hydrogenated" and is different than "partially hydrogenated".
One trans-free fry oil currently available to the food industry is comprised of mostly monounsaturated fat, primarily from low linolenic canola oil and antioxidants. New seed oils are also being bred to produce oils, which do not need hydrogenation. TOP
Follow the leaders.
Many major food processors have reformulated products to eliminate or reduce trans fats. Kraft now has an Oreo cookie with 0 grams of trans fat, and is working to produce low fat / fat free versions of Triscuits, Whole Wheat Crackers, Grahams, and Newtons. Crisco Brand has produced a shortening with zero grams of trans fat, made from a patented blend of sunflower, soy, and cottonseed oils. Campbell Soup Company, owner of Pepperidge Farm, has released Goldfish Crackers, one of America’s most popular snacks, with zero trans fat. (It is estimated that 65 billion goldfish crackers are consumed each year.) Frito Lay, a division of Pepsico, has also understood the implications of consumer health concerns. Their popular snack foods, including Fritos, Doritos, Cheetos, and Sunchips have undergone reformulation to eliminate trans fats. TOP
The Benefits of Eating Unsaturated Fats in Place of Saturated Fats. |
| Summarized from the text: Eat Drink and Be Healthy, Walter C. Willet,. MD |
| • Lowers level of low density lipoprotein (LDL – bad cholesterol) without also lowering the levels of high density lipoprotein (HDL – good cholesterol). |
| • Prevents the increase in blood triglycerides, another form of fat circulating in the bloodstream that has been linked with heart disease. |
| • Reduces the development of irregular heart beats, a main cause of sudden cardiac death. |
| • Reduces the tendency of blood flow blocking clots to form in arteries. |
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Nutrition Labeling Required by FDA.
It is only within the last few years that the case against trans fats or hydrogenated oils has become so evident to consumers and the food industry. Due to the impact of the medical research and epidemiological studies which support the statement that trans fat from partially hydrogenated oils promotes heart disease more than saturated fat, the government will require that trans fats be listed on Nutrition Facts Panels, by January 2006. Many food manufacturers already provide this information.
However, foods that contain natural sources of trans fats, such as beef and dairy, will not have a section for listing trans fat in their label. TOP
Labeling Confusion.
A question which arises often is: Why do manufacturers claim on the package that the food is trans fat free when a partially hydrogenated oil is listed on the list of ingredients section? The answer is that because under FDA regulations, if a product contains less than .5 grams of trans fat per serving size, they can express it as zero grams. This can be misleading if the defined serving size is so small that the entire package may actually constitute 2 or 3 defined servings. Thus, the actual intake of trans fat may total up to 1.5 grams when the entire package is consumed. Another misleading example is the term, "liquid frying shortening” as this is another way of saying partially hydrogenated oil. TOP
Balance.
While many health experts believe that trans fat plays an important role in the unprecedented rate of childhood obesity, cancer, heart disease, obesity and syndrome X, we must not lose sight that it is not the sole cause of our health problems. The overall diet is what makes a difference in health. Just focusing on foods that contain trans fat free ingredients will not correct these common health problems. Foods in appropriate amounts with healthy monounsaturated and polyunsaturated oils, fruits, vegetables, whole grains, beans, legumes, and lean meats are the foundation. Of course, discretionary calories in moderation are to be enjoyed, especially with so many of them now free of trans fats. TOP
| Fat Primer. |
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| Dietary fats differ in their chemical structures, culinary applications, and their role in health. |
| Type of Fat |
Main Sources |
| Monounsaturated |
Olives, olive oil, peanuts, peanut oil, cashews, almonds, peanut butter, avocados, canola oil |
| Polyunsaturated (omega 6 and 3) |
Corn oil, soy bean oil, safflower oil, fish oils, flaxseed |
| Saturated |
Whole milk, cheese, butter, red meat, coconut milk, coconut oil |
| Hydrogenated (Trans) |
Most margarines, vegetable shortening, partially hydrogenated vegetable oil, many deep fried chips, fast foods, and many commercial baked goods |
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