Polyunsaturated fats and why are they important for your health.

Polyunsaturated fats (PUFAs) are relatively long fat molecules and have "flex" points built into their structure called double bonds. Their longer length and multiple flex points enable them to play roles in our health that other fats cannot. For example, no other fats can play the same role in our cell membranes, allowing them to function properly. Nor can any other fats enable our body to produce regulators for controlling inflammation. Even genetic events are indirectly influenced by these unique polyunsaturated fats.

Much of the research interest in PUFAs has centered around two types: the omega-6s and the omega-3s. The balance between these two PUFA families turns out to be especially important for our health, including risk of cardiovascular diseases, inflammatory diseases, and prostate cancer.

The essential PUFA fats

All of the PUFAs in our body come from one of two places: we can eat them if they already exist inside our food, or we can make them inside of our body if we have the right building blocks. There are only two building blocks for making all PUFAs. One building block, called linoleic acid (LA), is used to make all of the omega-6 PUFAs. A second building block, called linolenic acid (ALA), is used to make all of the omega-3 PUFAs. Our bodies cannot make either one of these building blocks, and for this reason, both LA and ALA are considered to be essential fats that must be obtained from our diet. However, once we've eaten foods that contain appropriate amounts of LA and ALA, our bodies can make all of the other PUFAs that it needs.

Unfortunately, the average U.S. diet does not currently come close to providing appropriate amounts of LA and ALA. Most of the time, it also fails to provide enough overall PUFA intake. Many individuals in the U.S. get twice as many saturated fats as polyunsaturated ones, and within the polyunsaturated fats, they get precious few omega-3s. While there has been some debate over specific amounts, on average, U.S. adults fail to get even 1.5 grams of omega-3s on any given day, and by contrast, appear to be getting at least 12-13 grams of omega-6s, and perhaps as much as 14 grams or more. Part of the problem here has involved consumption of processed foods containing partially hydrogenated corn oil, cottonseed oil, or safflower oil, all of which are extremely high in omega-6s. (It's not the hydrogenation that is responsible for these high omega-6 levels, but rather, the oils themselves. Hydrogenation is a separate issue, and also a food processing step that is undesirable from a health standpoint.)