Over the past few months, I've posted several times on omega 3 and omega 6 fatty acids and why finding the right balance between the two is important for your heart health.
I haven't shared any information related to omega 9's, mainly to avoid confusion. I read a recent article discussing olive oil's link to reduced brachial artery blood flow and decided it was time to discuss omega 9's.
Let's start with the molecular difference between omega 9, omega 6, and omega 3. Here's a recap on what "omega" means from the post Get a Grip on Fatty Acids.
The term "omega" indicates which carbon has the first double bond on the carbon chain when you start counting from the omega end (remember "alpha" equals beginning and "omega" equals end). For omega 3, the first double bond is on the third carbon from the omega end of the carbon chain. For omega 6, the first double bond is on the sixth carbon from the omega end, while omega 9 has the first double bond on the ninth carbon. Okay, now that everything is clear as mud, let's move onJ
Types of fat
Omega 3's, 6's, and 9's are all heart healthy unsaturated fatty acids. But as we dive into the nitty gritty, some are more heart healthy than others.
Omega 3's are at the top when it comes to heart health. The more omega 3's (such as fish/fish oil rich in EPA/DHA and flaxseed rich in ALA) the better for heart health. Here's a previous post you may want to review - Top 5 Omega 3 Sources to Lower Cholesterol.
Omega 6's are found in vegetable oils, such as corn oil, which is very plentiful in the American diet. Omega 6 isn't inherently bad for heart health, what's bad is our excess intake of omega 6. The ratio between omega 6 and omega 3 is far from the ideal of 1:1 to 4:1.
Omega 9's are found in olive oil. Olive oil is 85% monounsaturated fat and contains minimal omega 3 or omega 6 fatty acids. Omega 9 fatty acids are not essential fatty acids like omega 3 and omega 6, because the body can produce omega 9 fatty acids from unsaturated fat.
To complicate matters a little further, just because you hear a particular oil is a good source of omega 3, does not mean it includes no omega 6 and vice versa. To explain this better, here is a table of the omega 6 and omega 3 content in 1 teaspoon of different oils.
Oil Omega 6 Omega 3
Fish oil 80 mg 850 mg
Flaxseed oil 610 mg 2510 mg
Safflower 640 mg 0 mg
Canola oil 920 mg 420 mg
Corn 2630 mg 80 mg
Even beef provides some omega 3's. A 3 ounce serving of sirloin steak provides 200 mg omega 6 and 70 mg omega 3.
(Source - I obtained the numbers above from ESHA Food Processor Software.)
Olive oil is 85% oleic acid and has little effect the omega 6 to omega 3 ratio. I like olive oil for this reason, but it can be argued that selecting oil that contributes omega 3's to your diet is more beneficial, even though you also gain omega 6's.
Dr. Dean Ornish claims that olive oil reduces blood flow by 31%. What he is referring to is reduced brachial artery (the main artery in the upper arm) blood flow, not coronary artery blood flow. For this reason, it's possible that the monounsaturated fat of olive oil is not the best choice to protect against arterial fat deposits when compared to other fats that offer more omega 3's.
However, I'm not changing my recommendations yet. I still encourage you to switch from standard vegetable oil or shortening to a more heart healthy cooking oil, such as olive or canola oil. This alone isn't going to give you dramatic heart health improvements. You need fish in your diet at least twice a week, select a supplement that will provide you at least 1000 mg of omega 3 fatty acids daily (choose a good source of DHA and EPA), use ground flaxseed when appropriate in your meal preparation, and select heart healthy nuts (such as walnuts) once in a while for a snack.