(24-11-07) Trans-Fats and the American Diet

(NewsTarget) All fat is not equal. Most of us are aware that there are good fats and bad fats. But the difference between the two can be confusing. For many years, we were told that unsaturated fat is better than saturated fat. We were also led to believe that if we avoid all animal fat, we are safe and that any vegetable fat is fine. Many of the country's professional medical associations have even promoted a "heathy" diet that is low in saturated fat for many years.

In reality, it is not that simple. As Enig and Fallon (1998, 1999) point out in their article "The Oiling of America" the American diet before 1910 was largely based on animal fats like butter, eggs, lard and meats, and coronary heart disease and heart attacks were rare. Americans also wre less sedentary and often ate locally produced food during those years. There was no refrigerated, cross-country trucking of foods in those days.

The American diet began to change toward one that included more industrially produced options, such as margarines, factory baked goods and vegetable oils in place of lard. Even though research in the '50's and '60's pointed to the fact that were fewer instances of coronary heart disease prior to the dietary changes, American companies were promoting their cereals, corn oil and margarines as beneficial to health and good for lowering cholesterol. It was around that time that the American Heart Association began a campaign (based on research done on rabbits, which are vegetarian animals) to change America's diet to a "Prudent Diet" where butter was replaced by margarine, breakfast cereals replaced eggs and chicken and fish in place of beef. The familiar food pyramid was created and even taught in public schools.

None of the research supported that dietary model. In fact, there were many published research reports that indicated that the opposite was true. Enig and Fallow write that "in 1961 the AHA published its first dietary guidelines aimed at the public. The authors, Irving Page, Ancel Keys, Jeremiah Stamler and Frederick Stare, called for the substitution of polyunsaturates for saturated fat, even though Keys, Stare and Page had all previously noted in published papers that the increase in CHD was paralleled by increasing consumption of vegetable oils. In fact, in a 1956 paper, Keys had suggested that the increasing use of hydrogenated vegetable oils might be the underlying cause of the CHD epidemic."

Now, more and more research is indicating that Keys was right in 1956. Trans-fats (hydrogenated vegetable oils) are dangerous to health and still in wide use. While most animal fat sources are saturated, which just means they are made of straight chains of carbon and hydrogen that pack together easily and are relatively solid at room temperature, most vegetable sources are unsaturated. They are formed by more crooked chains of atoms and since they don't pack together easily are more likely to be liquid at room temperature (or even below that).

In order to take a vegetable source and make it into a butter-like substance, you have to modify its structure. This process is called "hydrogenation" and was discovered and patented by a French scientist. Later, Proctor and Gamble obtained the rights to that patented process for use in the United States. Crisco OilT soon became the shortening of choice in American kitchens.

The problem with hydrogenation is that the process turns a healthy fat into a dangerous fat. According to Enig and Fallow's article, this process turns the vegetable-sourced unsaturated oils into straight "packable" molecules, by changing the placement of the hydrogen atoms at the location of their double bonds. In nature, most double bonds occur in the "cis" configuration, which means that both hydrogen atoms are on the same side of the carbon chain in the place on the chain where there is a double bond.

In the cis configuration, fats bend or kink at the double bond, preventing them from packing together easily. Hydrogenation moves one hydrogen atom across to the other side of the carbon chain at the point of the double bond allowing the chain to straighten out and become a "plastic" fat that can have a much higher melting temperature. In its normal state, unsaturated fats have that double bond site where vital chemical reactions take place. These reactions are critical to the ability of living cells to do their duties. When you create the trans-fat, you make a molecule that is similar enough to natural (saturated) fats that the body takes them in. Once they have been ingested, their altered chemical structure creates havoc with thousands of necessary chemical reactions-everything from energy production to synthesis of prostaglandins, which are critical to many body functions. Overall adverse effects are seen even when consumed in small amounts: 1% to 3% of total energy intake, or approximately 20 to 60 calories (2g to 7 g) for a person consuming 2,000 calories per day, according to the investigators. "Thus complete or near-complete avoidance of industrially produced trans fats may be necessary to avoid adverse effects and would be prudent to minimize health risks," said Dariush Mozaffarian, M.D., at the Harvard School of Public Health, and colleagues including Walter Willett, M.D., and Meir Stampfer, M.D.

The current research is so definitive about the harmful effects of trans-fat consumption, that many states have banned the use of trans-fats in public restaurants (like New York) and the Centers for Science in the Public Interest has filed a lawsuit against fast-good giant Burger King.

Trans-fats can hide in many food ingredients. In the CSPI news release they state that "Numerous fried and non-fried foods at Burger King have alarming levels of trans fat, according to CSPI. A King-size Onion Rings has 6 grams of trans-fat. A regular-size order of Chicken Tenders with a large order of French fries has 8 grams of trans-fat. A Sausage Biscuit with a large order of Hash Browns has an astounding 18 grams of trans-fat-more than someone should consume in 9 days." Another disturbing fact is that, even though most companies that label their food include the amount of trans-fat present, they are not require to report any amount less than one gram. So, if a serving has half of that, they don't have to report it. Eating several servings could, in fact, put someone over their daily safe consumption without knowing it.
Friday, November 09, 2007 by: Amy Daniels

Source: News Target.com

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