The WHOLE story of partially hydrogenated oils - manufacture, reason for inclusion in foods, effects on body, and...

What's the scoop on trans fats, also known as hydrogenated vegetable oils?

History

It's funny to think that the much of the use of trans fats began as a healthier alternative to the beef tallow once commonly used in cooking. In 1957, the American Heart Association began urging food companies and restaurants to find alternatives which were lower in saturated fat than butter and beef tallow. Eventually, because of this suggestion, the industry began to use trans-fats, which had actually been around for almost 50 years. In fact, Crisco vegetable shortening, as we still know it today, is almost 100 years old!

The industry found the application of trans fat to be a match made in heaven. It had a longer shelf life than either unadulterated vegetable oil or animals fats, it tasted better to many consumers, and generally reduced cost of producing foods. The trans fatty oils could remain in fast food fryers for much longer before going rancid.

Consumers found trans fats to be useful, as well. Households had been using margarine, a butter like substitute high in trans fats, for years-it was a solution which allowed a healthier, cheaper alternative to fully diary butter, while maintaining the same consistency.

Manufacture

Trans fats are made by hydrogenating vegetable oil. This process consists of heating the oil to a very high temperature and combining it with hydrogen gas and a metal catalyst, such as cooper or zinc. This process adds a hydrogen molecule to the oil's fatty acids, creating. This is a way to increase the saturation of the fat molecule, which is what makes trans fats act more like saturated fats by staying solid at room temperature.

Health Effects

The real problem with trans fats is that because their chemical structure is unlike any our body is accustomed to consuming, our body really does not know what to do with them. The liver responds to trans fats by producing much more very low density lipoproteins (VLDLs) and LDLs.

The health effects of trans fat consumption began to become visible in the 1990's, when numerous University studies indicated that the consumption of trans fats seemed to increase incidence of heart disease and low-density lipoproteins, or LDL's, which is the bad kind of cholesterol. Modern studies have also shown that diets rich in trans fats increase incidence of diabetes and create greater amounts of the exceptionally dangerous visceral fat-a layer of hard fat around the abdomen.

How much trans fat is too much? In 2002, the FDA declared that there is no safe level of trans fat consumption. In 2007, the head of the FDA said that foods with trans fats are as dangerous as foods contaminated by rodent droppings, a remark considered by many to be an overstatement of the risk. Nevertheless, it is no longer a subject of debate among professionals and researchers that trans fats are highly dangerous.

Avoiding Trans Fats

What is clear from all of the findings on trans fat is that they are to be avoided as much as possible. This can be a daunting task, given how widely used trans fats once were and still are. Fortunately for consumers, starting January 1st 2006, all foods with government mandated Nutrition Labels must disclose the amount of trans fat in the food. So, if the food has any fat, there will be a breakdown of the amount of Saturated Fats and Trans Fats in that food. There is one consideration with labels, however-trans fat is only required to show up on food labels if one serving of that food contains 0.5 grams of trans fat or more. Amounts less than this have been declared by the FDA to be "nutritionally insignificant." However, many consumers will consume more than one serving of a particular food, and if this is the case, the amount of trans fat consumed at a given sitting can multiply from less than 0.5 to several grams. If you suspect multiple servings to be consumed at once, look to the actual ingredients of the food, to see if it includes any oils that are partially or fully hydrogenated. This indicates that there is at least some trans fat in that food.

So, for many foods, avoiding trans fats is as easy as looking to the nutrition label. As a rule of thumb, one should look to the nutrition labels especially on foods that are baked (such as crackers or cookies or even pop tarts), foods that will be baked (such as brownie mixes) or foods that are fried (such as donuts). But really, it is important to check ice creams, pizza, and other foods which involve multiple ingredients. Some foods have high trans fats even though they seem healthy-such as already-prepared potato or bean products. Microwave popcorn has the very highest amount of trans fat of any food in a supermarket-some as high as 7 grams per serving. Also, it often seems to be the case that name brand manufacturers have already made the shift to trans fat free production, whereas generic brand counterparts have not. For example, at the local supermarket, name brand Pop Tarts have 0 trans fat, whereas the store brand has 1 g per serving.

What about foods without nutrition labels? This requires a bit more consideration. Most products from bakeries, besides bread (but sometimes including bread) will have a kind of trans fat shortening, so be weary of the cupcakes or donuts from your local bakery. Also, you should avoid any fried foods, because the french fries are probably the food with the very highest content of trans fat. One way to steer clear of trans fats outside the supermarket is to stick either with food that is fat free or foods that clearly use a meat or dairy fat. Ultimately, the only way to be sure is to eat at restaurants that have declared they use trans fat free cooking oils and ingredients (to date, a number of fast food restaurants, such as Kentucky Fried Chicken, have taken this step).

Possible Substitutes

Really, there have always been substitutes for trans fat, though many of them are unsatisfactory. In frying, trans fat free oils become rancid much more quickly and must be changed more often. As far as baking, one can use beef tallow or full dairy butter, though these have such high saturated fat contents as to make them hardly an appropriate substitute. The industry is still working to develop the perfect substitute-longer shelf life, solid at room temperature (a must for baking), and healthy.

In the mean time, the best we can do is to use tub margarine, much of which can be found to be fat free. This butter substitute can be used in cooking, though effects will vary from trans fat shortening. And its not quite solid at room temperature, so the texture may take some getting used to for those who are used to real butter or trans fat rich margarine. Its very important to look to the nutrition labels of butter or margarine, and if its in a stick, its almost certainly trans fat rich. Many find tub margarine to be a very appropriate and effective substitute, and it is the closest the industry has come.

Conclusion

We are just beginning to see the full health effects of trans fats, and consumers can rest assure that these fats have been well proven to be dangerous. The campaign against trans fats is not merely another health fade or media induced scare. And while avoiding trans fats can be a difficult task and can limit choices while eating out, a sensible approach can greatly limit trans fat intake while maintaining an enjoyable, healthy and diverse diet.