Fat. It keeps us full. It flavors our food. It gives us energy. It also clogs our arteries and raises our cholesterol levels. While some fats are better than others, others are just plain bad for you - like trans fats.

Trans fats are generally formed when liquid vegetable oils go through a chemical process called hydrogenation. Hydrogen is added to oils to make them more solid and food processors love to use them to extend the shelf life of food, as well as to better taste and texture. Not all trans fats are manufactured though, some do occur naturally, in small amounts. They can be found in some meat, a quarter pound of ground beef has 1.33 grams of trans fat, and one cup of milk has .24 grams.

Fear not New Yorkers, the city is only banning artificial trans fats, so you will still be able to eat cheeseburgers in the Big Apple. The truth is, the majority of Americans eat more artificial trans fat than the naturally occurring kind,

The FDA, however, has a different take, and they group all trans fats, be they artificially or naturally occurring, all the same. In 2006, the FDA began requiring manufacturers to list on their products if they contain a half a gram or more of trans fat per serving. The amount must be included on the food label and the food can’t be called trans fat-free, even if butter (naturally occurring) is the only fat. Another reason to read ingredients carefully.

Want to know about trans fat and Starbucks? Then read more

Interestingly enough, the FDA label rule does not apply to foods overseen by the US Department of Agriculture, namely meat and poultry. That is why you will not see the amount of trans fat listed on the ground beef you pick up at the grocery.

Starbucks is taking a slightly different route than NYC and asking all their bakers to remove all but .5 grams of trans fat, artificial or otherwise, from their baked goods. The company feels that "trans fat free" reads better than "artificial trans fat free" - guess they think we consumers can only handle three word descriptions of our food. Bakers are reworking recipes that use butter to ensure their pastries have under a half a gram of trans fat to satisfy the new requirement. Many large scale bakeries are on the hunt for trans fat free margarine.