For some years, we've heard that saturated fats are bad for us. Now, many people are pointing their fingers at trans fats.

Trans fats are created in the process of hydrogenation, which adds hydrogen to oil. The words "hydrogenated" or "partially hydrogenated" on the label signify that a product contains trans fats. Eating trans fats raises your chance of having a heart attack, according to a study in a 1997 New England Journal of Medicine. Trans fats have also been proven to raise LDL cholesterol, which is the bad cholesterol.

Hydrogenated fats do not spoil for a long time, and they have long shelf lives. This makes them very practical for the manufacturer and the consumer. Trans fats can be found all over the grocery store shelves in things like margarine, crackers, potato chips, cookies and many other foods.

With the saturated fat hysteria, Americans thought they had to avoid fats altogether, but it turns out that we need some fats. Research in the last few years has revealed that a moderate, daily dose of the right kind of fats (polyunsaturated and monounsaturated) is healthier than no fat at all. These unsaturated fats contain essential fatty acids (EFAs) that actually protect the brain, heart and blood flow. The EFAs are omega 3, omega 6 and omega 9 oils. They are said to fight heart disease, but their link to diabetes has not yet been firmly established in scientific journals.

Are They That Bad?

Some evidence suggests that as long as you have the protection of EFAs, you may even be able to eat trans fats. In 1998 a Norwegian medical journal wrote, "Provided the diet contains sufficient amounts of essential fatty acids, there are no strong indications that trans fatty acids may have other unfavorable effects on health."

Trans Fats and Type 2s

Trans fats are named as a cause of bad health in a new book, "The Other Diabetes: Living and Eating Well with Type 2 Diabetes." Author Elizabeth Hiser, a dietitian, health writer and editor, advocates the "Good Fat Diet," which consists of avoiding saturated fats and trans fats.

"Eating too much saturated fat is probably the worst thing you can do," Hiser warns in the book. "Not only are they bad for your heart, there is evidence that they also may be involved in insulin resistance. Saturated fats cause insulin levels to remain high after a meal."

Hiser also discusses trans fats.

"Whenever you see the word hydrogenated on an ingredient list," she says, "substitute the word saturated in your mind, because hydrogenated fats are artificially saturated."

Hiser uses this evidence to advocate the "Mediterranean-style eating pattern," with good fats like olive oil and flaxseed oil, which provide protection against omega-3 oil. Besides a healthy amount of good fats, the Mediterranean diet includes lots of beans, vegetables and grains.

Going Mediterranean

Hiser discovered the Mediterranean diet while working as nutrition editor at Eating Well magazine. However, she has been arguing against trans fats for years as a dietitian.

"Twenty years ago, I read about animal research that suggested trans fats were cancer promoters," she recalls. "Even back then, I taught cardiac patients not to use margarine, but to use liquid oil instead."

As a research dietitian at the University of Vermont, Hiser studied diabetes, obesity and insulin resistance, then used this knowledge at Eating Well to communicate healthy eating habits.

"At Eating Well, we got so many letters from type 2s who had no clue what they were doing, because there's so much misinformation and misunderstanding out there," says Hiser. "Dietitians are still telling people that margarine is okay. I say, you have a choice, why not take the fats that are safe?"

Hiser recommends olive oil for pan grilling and canola oil for baking.

The American Way

Hiser believes these wrong messages come partly from the American food industry, which produces the trans fats.

"I suspect that the messages are based on economic interests," she states. "The United States doesn't produce olive oil or canola oil. Olive oil often comes from Italy-some does come from California-and canola oil comes from Canada."

Hiser states that America is obsessed with being fat free, instead of being obsessed with good food, containing good fats.

"It makes far more sense for you to spend your calories on a plate of fresh greens dressed with a little olive oil, rather than on a few fat-free cookies," she writes. "Containing little more than refined sugars and flour, the cookies will raise your blood sugar and most likely your triglycerides. The fat-containing meal will do neither."

Hiser's book includes many Mediterranean recipes for type 2s, and can be found at Amazon.com.

Insulin Resistance

A group of researchers at the University of Pierre et Marie Curie in Paris, have looked at fish oil supplements and their effect on insulin resistance. In 1996, a study in the August Journal of Nutrition revealed that in insulin-resistant rats, fish oil improved insulin action, while rats fed vegetable and animal oils did not gain this improvement.

In 1998, the same team of doctors conducted similar research in humans, which Diabetes Care published in May of that year. Type 2 males took either fish oil or sunflower oil supplements. The humans did not see an improvement in insulin action like the rats, but fish oil did improve their lipid (fatty particles) profiles more than the sunflower oil did.

For now, the connection between trans fats and insulin resistance remains unclear. It appears to be a subject on the verge of intense scrutiny in the research world, which could lead to more definitive proof on how it affects type 2 diabetes.

EFAs: Part of Balanced Diet

As most people have figured out, it is practically impossible to eat no fat at all. You can feel good about eating fatty foods, as long as you are eating the right kinds and amounts of fats. Even the healthy, protective EFAs can be harmful if one eats too many of them. We should stick to a balanced diet and not eat too much of any good thing.