Big fat report on fats

Here are my notes from reading up on fats and oils for cooking, following lots of discussion at our nutrition talk in the gym yesterday.

Industrially produced polyunsaturated fats (“PUFAs”) have been all the rage for cooking in recent decades because they are “vegetable oils” that don’t contain cholesterol. Examples: corn oil, vegetable oil, canola oil, Crisco. Paleo-diet researchers point out that these are undesirable because they contain too much omega-6 fat (which we get too much of today) and/or because they’re manufactured in processes that completely remove them from any semblance of the whole food they may have come from.

Omega-6 and omega-3 (a/k/a N-6 and N-3) fatty acids are PUFAs. Some of the omega-3 fatty acids can’t be produced in the body from other fats, so it is essential to have them in the diet. (The word “essential” with regard to nutrition, by the way, means specifically that the body can’t make it, so we have to eat it to live.) The “3″ in omega-3 refers to the structure of the carbon chain in the molecule. Paleo diet experts believe preagricultural man–hunter-gatherers–ate about twice as much N-6 as N-3 fats. Today, we eat 6 to 22 times as much N-6 as N-3. Both are necessary, but the fact that we get too much N-6 is one of the dietary problems that exacerbates inflammation in our system. We need to get more N-3 through eating fatty fish, including salmon and canned sardines, and by taking fish oil. And we need to reduce the amount of N-6 that we eat. On a paleo diet, we can do that by not using the “vegetable oils” mentioned above and by not eating a lot of nuts. A paleo diet eliminates the processed foods that are made with loads of N-6 fats.

Monounsaturated fats: “monounsaturated” refers to the molecular structure of the carbon chain. Wikipedia says: “Monounsaturated fats are found in natural foods such as red meat, whole milk products, nuts and high fat fruits such as olives and avocados. Olive oil is about 75% monounsaturated fat. Canola oiland Cashews are both about 58% monounsaturated fat. Tallow (beef fat) is about 50% monounsaturated fat and lard is about 40% monounsaturated fat.” It’s good to remember that most foods contain a combination of types of fats. (Even lard isn’t 100% saturated fat!) Monounsaturated fats are good on salads and low temperature usages. They break down and become rancid more quickly at high temperatures than saturated fats. (So do PUFAs.)

Saturated fats are solid at room temperature. They are stable, meaning it takes a lot more heat to oxidize them (make them rancid), so they’re great for stir-frying. They don’t oxidize in the body. They are also delicious! Saturated fats have had a bad reputation, and the phrase “artery-clogging” always seems to precede “saturated fats.” But in the absence of inflammation, saturated fats do not cling to arteries or flake off to cause problems. An anti-inflammatory, whole foods diet like a paleo or primal diet is currently believed by paleo diet researchers to safely include saturated fats such as coconut oil, pastured lard, tallow, and butter (if you tolerate dairy).

Ideally, when starting a paleo diet, you should have your cholesterol checked and determine the ratio of HDL to total cholesterol (total divided by HDL — you want high HDL for a lower ratio); you should also find out your fasting blood glucose; triglycerides; and blood pressure. On a high-fat paleo diet plus CrossFit, you typically might have a bit higher total cholesterol but an excellent ratio of HDL to total. And your triglycerides will likely plummet.

This is not medical advice. At CrossFit 206 we are trying to communicate with you about our direct, personal experience and about the research sources we trust.

Sources:
Wikipedia

http://thepaleodiet.com/published-research

Loren Cordain: The Paleo Diet; The Paleo Answer
Robb Wolf: The Paleo Solution