Saturday, October 20, 2007

Selecting Fats and Oils for Health

One very important influence on our health is our choice of fats and oils in our diet. In general, we should look for oils and fat that are close to what is found in our bodies - mostly saturated and monounsaturated, with only a small amount of polyunsaturated fat. Below is a table showing the percentage of these types of fat in various fats and oils that we eat. The omega-6 and omega-3 fats are also included in the polyunsaturated total in this table. We need small amounts of omega-6 fat, but most people eating a Standard American Diet (SAD) get way too much of this type of fat and that depresses your immune system and increases your chances of getting cancer and heart disease. It's best to avoid fats/oils that have more than about 20 percent as omega-6 and use sparingly fats/oils that are more than about 10 percent omega-6. Oils high in omega-6 are commonly used in processed/packaged foods and in restaurants because they are inexpensive and because of misguided advice to avoid saturated fats. Because of the polyunsaturated bonds, the high omega-6 oils easily go rancid and are easily damaged in processing and cooking. Also be sure to read "Some Typical Questions and Misconceptions on Fats and Oils" by Mary Enig, PhD nutritionist and "The Great Con-ola".

Percentage of Classified Fats for Different Fats and Oils
Fat/oilOmg-6Omg-3PolyMonoSat
Cod liver oil1.020.524.550.924.6
Palm kernel oil1.70.01.712.186.2
Macadamia oil1.80.32.181.516.4
Coconut oil1.90.01.96.291.9
Butter oil (ghee)2.41.53.930.565.6
Butter2.90.44.027.968.1
Beef fat (tallow)3.20.64.243.752.1
Sunflower high oleic oil3.70.23.986.110.0
Mutton fat (tallow)5.72.48.242.449.4
Palm oil9.50.29.738.751.6
Olive oil10.00.810.875.014.2
Goose fat10.30.511.559.429.0
Pork fat (lard)10.71.011.747.241.0
Duck fat12.61.013.551.734.8
Avocado oil13.11.014.173.812.1
Flax oil13.355.869.021.19.8
Safflower high oleic oil15.10.015.178.46.5
Almond oil18.20.018.273.28.6
Canola (rape seed) oil19.29.228.564.17.5
Chicken fat20.41.021.946.931.2
Peanut oil33.60.033.648.617.8
Rice bran oil35.51.737.241.821.0
Sesame oil43.20.343.641.514.9
Soybean oil53.07.160.023.716.3
Cottonseed oil53.90.254.318.627.1
Corn oil56.21.257.429.013.6
Sunflower oil68.80.068.820.410.8
Grapeseed oil72.80.173.116.810.0
Safflower oil78.40.078.415.16.5
Compiled from USDA Nutrient Database
Note: about 4 to 6 percent of total fats were unclassified

Table Abbreviations
Omg-6: Omega-6
Omg-3: Omega-3
Poly: Polyunsaturated (including both omega-6 and omega-3)
Mono: Monounsaturated
Sat: Saturated

10 comments:

Anonymous said...

Thank you for posting an easy reference. God Bless You.

mks

Jo said...

Thank you for this chart. Makes my transition to my once casual observance of my omega 6/3 ratio to the now steadfast one. I might be able to spend less on fish oil this way, thank you.

Bryan - oz4caster said...

jo, keep in mind that omega-3 from vegetable sources is in the form of linolenic acid which must be converted in our bodies to longer chain EPA and DHA to be used and this conversion is not always very efficient. It's better to get omega-3 from animal sources, where it is already in EPA and DHA form, as in cod liver oil.

Kelly said...

GREAT CHART! I'll be sure to link to it when I get my own post ready on the topic of healthy fats. (www.kellythekitchenkop.com)
Thank you!

Bryan - oz4caster said...

Kelly, thanks for dropping by. I like your blog and added it to my "Healthy Cooking Ideas" list.

David B. Thomson said...

Great Job, I wish I would have written this! I will place a link on my website.!

Billy Two Shoes said...

I wonder how much the quantities for the animal fats would change depending on their feed. For example, would pig and chicken fat contain less omega 6 if they were raised on pasture, and not fed soy or corn? Are these numbers based on conventionally raised livestock?

Bryan - oz4caster said...

That's a good question and I'm afraid I don't have any good data specifically for fats and oils to answer it directly. The data in this table if from the USDA nutrient database and is most likely from conventional sources. They do have data on wild animal meats and I have noticed that fat in the meat of wild boars has much less omega-6 than in conventional pork loin, mainly because there was less total fat in the boar meat, 4.4 grams versus 25.3 grams per 100 gram amount for the total fat. However, the percentage of fat as PUFA is much higher in wild boar meat, with 17.5 percent of the fat as PUFA in the boar meat and 9.0 percent as PUFA in the pork loin meat by weight. I have seen similar data on chickens that indicates less fat in pastured chickens, but the percentage of omega-6 relative to the total amount of fat may be slightly more if I remember correctly. Pastured ruminant meats also tend to have less fat than conventional grain finished ruminant meats, but the amount of omega-6 is still relatively small in conventional ruminant meat relative to the total amount. From what I remember, the amount of omega-3 is typically higher in all pastured animal meats compared to conventional meats and pastured ruminant meat also has conjugated linoleic acid (CLA) that is largely missing in conventional animal fats. CLA is a trans-fat, but is the only good trans-fat. As you probably know, artificial trans-fat created by partial hydrogenation of high PUFA oils is quite bad for health.

Billy Two Shoes said...

Another question I hope you might be able to answer: it is said that you should avoid heating your polyunsaturated fats, including omega 3s. Does that mean that you can't rely on most animal sources for your Omega 3 because presumably you're going to be cooking them?

Bryan - oz4caster said...

I'm not a chemist, but my best guess from what I've read is that omega-3 fats will gradually go rancid when exposed to air, from reactions with the oxygen, ozone, and other reactive oxygenated species. Heating most likely speeds up this process, but the omega-3 has to be exposed to oxygen radicals, which may be less likely inside meat. Cooking meat at lower temperatures is probably less harmful to the omega-3 than frying, broiling, or other high heat methods. You can also get good omega-3 by eating raw eggs from pastured chickens or from traditionally fermented cod liver oil. Some people eat meat raw, as in sushi, ceviche, or steak tartare, for instance. I recommend freezing it for at least two weeks before consuming it raw to minimize risk from bad microbes or parasites.