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Why do trans fat and saturated fat get such a bad rap?

        Health | Cholesterol

Perp No. 2: Trans Fats
Trans fats have received so much bad press that many food manufacturers go out of their way to proclaim their product free of the stuff. But if one of the ingredients listed is a type of partially hydrogenated oil, watch out.
Trans fats have received so much bad press that many food manufacturers go out of their way to proclaim their product free of the stuff. But if one of the ingredients listed is a type of partially hydrogenated oil, watch out.

There's a reason why cream cheese has such a nice, smooth, consistent quality to it when you open a new package. That block of cream cheese, along with lots of other foods, has likely been made with vegetable oil that's been altered.

Before food makers add vegetable oil to cookies, crackers, doughnuts, french fries and other stuff, they heat the vegetable oil (often soybean oil). Then, they force bubbles of hydrogen into the oil at high pressure. As the hydrogen atoms bond to the carbon atoms in the oil, the new substance -- partially hydrogenated oil -- becomes more solid. (If you fully hydrogenate the oil, it can become almost as hard as a rock.)

Partially hydrogenated vegetable oil is creamy and cheaper than butter, qualities that make it appealing for both food manufacturers and consumers. Using this altered oil increases the food's shelf life and decreases its greasy feel, but it's very, very bad for you.

This partially hydrogenated oil has another name: trans fat, or trans fatty acid. Trans fat is used in countless food items like biscuits, pizza dough and stick margarine, and it wreaks havoc on your heart over time. Not only do trans fats raise your bad cholesterol (LDL) levels, they simultaneously lower your good cholesterol. With less good cholesterol and more bad cholesterol, you become more likely to have hardened, clogged arteries. That bad cholesterol builds up as plaque on the inside of your artery, but it's not very stable. One day, a little piece of that plaque will break off, your body will try to clot up the nick in the artery, and it's Heart Attack City.

Before 1990 or so, ignorance was bliss. We were eating tons of trans fats for the same reason we once installed asbestos in our homes: It seemed to work, and we didn't know any better. Now the U.S. Food and Drug Administration recommends that you eat less than 2 grams of trans fats per day. For perspective, a single donut can have as much as 5 grams of trans fat [source: Davis].

Increased awareness of the dangers of trans fats and several lawsuits have led many fast-food restaurants (most famously KFC) to switch to nonhydrogenated cooking oils. Many cities, such as New York, and even one state, California, have banned the use of hydrogenated oils in restaurants. Interestingly, some trans fats are found naturally in beef, lamb and butterfat, but experts aren't sure if these natural trans fats produce the same negative health effects.

Many packaged food items in your grocery store will have "No Trans Fats!" boldly splashed across the front of the box. In the dietary information on the back of the box, you see it again -- "Trans fats … 0 g." But incredibly, when you look at the list of ingredients, there it is: "Partially hydrogenated soybean oil." What gives? That's trans fat, right? Right. Food manufacturers can label their products as having no trans fats if they contain less than half a gram per serving.

Your best bet is to scan the list of ingredients and look for shortening or partially hydrogenated soybean oil. If they're listed, you're about to dive into some trans fats, no matter how much the rest of the packaging denies this fact.

Limiting or cutting trans fats and saturated fats out of your diet will go a long way toward keeping that beautiful heart of yours nice and healthy. Continue reading for lots more information on saturated fats, trans fats and heart health,­ and to learn if the cure for heart disease is one carrot away.