Food companies have tried to obtain the useful features of saturated fat without its artery-blocking potential by using vegetable oil but changing it chemically. In a process called partial hydrogenation, they bubble hydrogen through vegetable oil, converting the oil to a firmer, less perishable form rich in a substance known as trans-fat. Trans-fatty acids are manufactured fats created during a process called hydrogenation, which increases the shelf life of products including stick margarine, fast foods, commercial baked goods (donuts, cookies, crackers), processed foods and fried foods. These fats recently have been proven to cause significant lowering of HDL. In other words, the body has no need for trans fat, which acts like saturated fat in the body and promotes higher level of low-density lipoprotein (LDL), the ‘bad’ cholesterol, and lower levels of high-density lipoprotein (HDL), the “good” cholesterol. Until now consumers have been unable to determine the trans-fat content of their food unless they looked for the phrase “partially hydrogenated vegetable oil” on ingredient labels.2 The difference between a “fat” and an “Oil” is temperature. A fat is a lipid that is solid at room temperature whereas, “oil” is one that is liquid at room temperature. Here are the essential facts about the major fats in foods:
Saturated fat: this fat is “saturated” with stabilizing hydrogen atoms, which make it solid at room temperature and slow to spoil. Abundant in meat and dairy products, saturated fat tends to increase the “bad” LDL cholesterol, and it possibly may raise the risk of certain types of cancer.
Polyunsaturated fat: The molecule of this fat has two or more unfilled hydrogen slots, making the fat liquid at ordinary temperature and quick to turn rancid. Polyunsaturated, the major constituent of certain vegetable oils such as corn and soybean, actually tend to lower LDL cholesterol but may reduce the “good” HDL cholesterol as well.
Monounsaturated fat: There’s only one unfilled hydrogen space in a monounsaturated fat, making it somewhat denser and more stable than a polyunsaturated fat. Monounsaturated, the main fats in olive, canola, and peanut oil, tend to lower LDL, and some studies suggest that they may do so without depressing HDL. One other advantage is that monounsaturated apparently do not raise the risk of cancer.
Trans-fat: Manufacturers create this fat when they force hydrogen through an ordinary vegetable oil. This “Partial hydrogenation” fills a few empty hydrogen spaces, converting some polyunsaturated to monounsaturated, and some monounsaturates to saturates. The process also flips some of the existing hydrogen atoms in the unsaturated fats in to a more sable configuration, known as trans that straightens and hardens the molecule, giving its properties of a saturated fat.1
What is Hydrogenation?
Hydrogenation is the process of heating oil and passing hydrogen bubbles through it. The fatty acids in the oil then acquire some of the hydrogen, which makes it denser. If you fully hydrogenate you create a solid (a fat) out of the oil. But if you stop part way, you get a semi-solid partially hydrogenate, oil that has a consistency like butter, only it’s a lot cheaper.3
What is wrong with hydrogenation?
Unlike butter, hydrogenated oil contains high levels of trans-fat. A trans-fat is an otherwise normal fatty acid that has been “transmogrified” by high-heat processing of free oil. The fatty acids can be double linked, bond-shifted, twisted, or messed up in variety of other ways. The problem with trans-fat is that while the “business end” (the-
Chemically active part) is messed up, the “anchor end” (the part that is attached to the cell wall) is unchanged. So they take up their position in the cell wall, like a guard on the fortress wall. But like a bad guard, they don’t do their job!They let foreign invaders pass unchallenged, and they stop supplies at the gates instead of letting them in. In short,
Trans-fats are poisons, just like arsenic or cyanide. They interfere with the metabolic process of life by taking the place of a natural substance that performs a critical function.3
Hydrogenation process
The hydrogenation process employs (1) high heat (2) a metal catalyst such as nickel, zinc, copper or other reactive metals. (3) Hydrogen gas. The metals are used to react with the hydrogen gas, which is bubbled up through the mixture. The metals catalyze the hydrogen and carbon atoms and convert the fatty acids by flipping one of the attached hydrogen molecules and rotating it half the diameter of the carbon chain. This effectively creates a new molecular shape resulting in a stiffer or more rigid material, hence the change from a liquid to a semi- solid substance. This new shape stiffens with the hydrogenation process making the oil behaves like saturated fat, (such as coconut fat which is 92% saturation and solid at room temperature).1
Partially hydrogenated oils make you fat!
Partially hydrogenated oils will not only kill you in the long term by producing diseases like multiple sclerosis and allergies that lead to arthritis, but in the mean time they will make you fat! Partially hydrogenated oils make you gain weight the same way that saturated fats do by making you consume even more fat to get the essential fatty acids you need. But partially hydrogenated fats are even worse, not only do they produce disease over the long term, but they interfere with the body’s ability to ingest and utilize the good fats. Picture it this way; the trans-fats are now the guards along the watch tower, the essential fatty acids (the support troops) are waiting outside to get into the fort (the cell) so they can be distributed along the watch tower (the cell wall). But the guards won’t let them in! So they have to find some place to stay in town. Over time, more and more troops are finding lodging in town. So, new houses (fat cells) have to build to keep them in. The town grows more and more swelled with troops (fat) and it gets bigger and bigger (fatter). It’s not a pretty picture at all, when you realize that the town is your belly, buns, face, and neck.3
Do fatty foods weaken bones?
Research findings show that what’s bad for your heart may also be bad for your bones. The problem stems from the hydrogenated vegetable oils (like margarine and shortening) often used to make baked goods and convenience foods. It turns out that hydrogenation, a process by which liquid vegetable oils are partially solidified, not only creates trans-Fats (which are bad for you heart) but also destroys the vitamin k naturally found in vegetable oils. Your bones need vitamin K, and vegetable oils are one of the most common dietary source. But as you consume more hydrogenated oils, you’re eating less healthy oils and thus lowering your intake of vitamin K.2
In general limit your intake of commercial baked goods and fried foods, and consider the over all fat content of foods you buy. If a product is low in fat, the hydrogenated oils are likely to be less of a problem! Avoid the cholesterol raising fats such as margarine-fried fast foods, and packaged foods. Although there is no formal recommendation on the exact amount, nutritionists advise limiting trans-fat and saturated fat to about 10% or less of daily calories. So a person who eats 2000 calories a day should aim for no more that about 22 grams of these two fats.3
References:
1.Gupta; Sanjay.HHATF. Sep.2002, 160,85.
2. Mc Cord; Holly, McVeigh; Gloria. ZIOHF.Feb 2003,55,56.
3. Schlosberg; Suzanne; shape. ICTLP. Oct 2002, 22, 102.
