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Originally published March 3 2008

Interesterification - The Dangerous Replacement for Trans Fats

by Frank Cooper

(NaturalNews) Due to the terrible health problems associated with trans fats, the food industry has been busily perfecting another 'man-made' replacement to ensure that company sales and profits are kept at a high level. The new solution is a process called interesterification, a technique for making butter-like products from liquid vegetable oils. Interesterification can be used to make margarines, shortenings, baked goods, and confectionary that requires the texture, mouth feel, and smoothness similar to saturated fats.

So what is Interesterification? It is a process that uses enzymes to alter the molecular structure of a vegetable oil, to give it the properties of a fat. Let's look at the process of interesterification.

The interesterification process involves taking a batch of vegetable oil, to which we add an enzyme that acts as a catalyst. The catalyst causes the separation of a triglyceride molecule into a glycerol and 3 fatty acids.

After breaking the triglycerides molecule apart, the factory can re-configure the fatty acid molecules – combining any three Omega 3, Omega 6, Omega 9, or Saturated molecules, in whatever combination they seek.

Depending on this combination, ie. the percentage of lighter Omega 3 or 6 versus the heavier Omega 9 and Saturated molecules, the hardness of the fat will be determined. The interesterification process can produce any type of fat or oil. This includes heavy fats suitable for deep-frying, semi-solid fats to make margarine, or liquid oils for bottling; the end result is a product that has an indefinite shelf life, targeted at the unsuspecting consumer.

One question that you might ask is, "If vegetable oils are mostly liquid, how can interesterification make them solid?" "Where are the saturated fatty acids coming from to solidify the oils into a fat?" Well this is achieved by hardening some of the vegetable oil - by bombarding the liquid oils with hydrogen in a process called hydrogenation. In other words the hydrogenation process is still a key part of the interesterification process but there are no trans fats. Unfortunately these new vegetable oil/fats made via interesterification have a molecular structure that the human body has never seen before. And there lies the problem.

One thing to remember is that the interesterification processes explained above takes place after the sanitization process that occurs earlier in the oil processing plant. Let's remind ourselves of that purification process:

"The seeds are firstly ground by a grinding machine, and then steam cooked, and thereafter mixed with solvents to dissolve out the oils. The most popular solvents are Hexane or Trichlorethylene and both are very carcinogenic. The oils and solvents are then separated, and minimal traces of Hexane remain in the oil. The oil is then refined with the addition of sodium hydroxide and temperatures are increased to over 200ºC / 400ºF. Thereafter the oil is treated with carbon that removes all the Vitamin A, E, F, Lecithin, Chlorophyll, and other nutrients. Preservatives and/or anti-oxidant additives like BHA/BHT are added later."

In summary, the vegetable oils first go through the purification as described above, followed by the hydrogenation process, and then interesterification. Can you see why natural fats like butter are the way to go? No one knows the consequences of eating the newer interesterified oils/fats because no long term trials have been done. And cancers take years to develop. Some preliminary testing indicates that interesterified oils have the same risks as trans fats.

Currently there is no legislation covering interesterification, and you are unlikely to see it mentioned on any food labels. So if margarine, cakes, biscuits or other food product states 'vegetable oil' then you can be absolutely certain that it contains either interesterified fats, or trans fats. There is simply no other commercially viable way to produce a solid fat from vegetable oils that are suitable for baked goods.

In other words, if you see 'No Trans Fats' on a packet of cake or biscuits made from vegetable oils, then you can be certain that it contains highly processed interesterified, or fully hydrogenated vegetable oils.

In Summary:

From research done in the last twenty years we've learned that processed vegetable oils are a serious threat to our health for the following reasons:

1) The big problem with processed vegetable oils is at the cell level. Since these fats don't occur in nature, our bodies don't know how to deal with them. The body tries to use them, thinking they are normal fats, and they wind up in cell membranes and other places where they behave strangely. These man-made fats weaken the cell membrane, particularly their protective structure and function.

2) The big threat to males is coronary heart disease. In males, processed vegetable oils appear to activate the body's immune responses when they enter the artery walls, because these fats do not resemble anything that the body recognises, so the body attacks it. This directly leads to an inflammatory response in the arteries which leads to the formation of dangerous plaque build-up.

3) In the case of women it's a bit different. These processed vegetable oils manage to somehow bypass the immune response at the artery wall. However they move further along into the body, and are deposited into the fatty tissues such as in the breasts, where they directly contribute to cancer.

4) A major problem with processed vegetable oils is the residue of toxic metals, usually nickel and aluminium, left behind in the finished product. These metals are used as catalysts in the reaction, and they accumulate in our nervous system where they can lead to neurological conditions. These heavy metals also poison enzyme systems and alter cellular functions, and cause a wide variety of health problems. These toxic metals are difficult to eliminate, and our 'toxic load' increases steadily with small exposures over time.

Remember it took 30 years to learn that trans fats were a disaster, and it will take just as long to learn the same about interesterified fats.

About the author

Frank Cooper is a Naturopathic Nutritionist based in Australia. He is the author of the book "Cholesterol and the French Paradox" released in 2006 that explains the reasons the French enjoy low levels of heart disease. His clinic is based in the Hunter Valley, one of Australia’s premier wine regions. For more information visit his website or his vineyard


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