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A Reply to Ray Peat on Essential Fatty Acid Deficiency PDF Print E-mail
Written by Mary G. Enig, PhD   
Wednesday, 03 August 2005 20:39

Ray Peat, PhD, is an influential health writer who claims that there is no such thing as essential fatty acid (EFA) deficiency. According to Peat, the body can make its own EFAs; furthermore, he claims that EFAs in the body become rancid and therefore cause cancer.

Unfortunately, Peat does not understand the use of EFA by the human body. He is trained in hormone therapy and his training in fats and oils has been limited to misinformation as far as the polyunsaturated fats and oils are concerned.

Research on EFAs is voluminous and consistent: EFAs are types of fatty acids that the body cannot make, but must obtain from food. We do not make them because they exist in virtually all foods, and the body needs them only in small amounts. The body does make saturated and monounsaturated fatty acids because it needs these in large amounts and cannot count on getting all it needs from food.

There are two types of EFAs, those of the omega-6 family and those of the omega-3 family. The basic omega-6 fatty acid is called linoleic acid and it contains two double bonds. It is found in virtually all foods, but especially in nuts and seeds. The basic omega-3 fatty acid is called linolenic acid and it contains three double bonds. It is found in some grains (such as wheat) and nuts (such as walnuts) as well as in eggs, organ meats and fish if these animals are raised naturally, and in green vegetables if the plants are raised organically.

Essential fatty acids have two principal roles. The first is as a constituent of the cell membrane. Each cell in the body is surrounded by a membrane composed of billions of fatty acids. About half of these fatty acids are saturated or monounsaturated to provide stability to the membrane. The other half are polyunsaturated, mostly EFAs , which provide flexibility and participate in a number of biochemical processes. The other vital role for EFAs is as a precursor for prostaglandins or local tissue hormones, which control different physiological functions including inflammation and blood clotting.

Scientists have induced EFA deficiency in animals by feeding them fully hydrogenated coconut oil as their only fat. (Full hydrogenation gets rid of all the EFAs; coconut oil is used because it is the only fat that can be fully hydrogenated and still be soft enough to eat.) The animals developed dry coats and skin and slowly declined in health, dying prematurely. (Interestingly, representatives of the vegetable oil industry blame the health problems on coconut oil, not on fatty acid deficiency!)

In a situation of fatty acid deficiency, the body tries to compensate by producing a fatty acid called Mead acid out of the monounsaturated oleic acid. It is a 20-carbon fatty acid with three double bonds named after James Mead, a lipids researcher at the University of California at Los Angeles who first identified it. An elevated level of Mead acid in the body is a marker of EFA deficiency.

According to Peat, elevated levels of Mead acid constitute proof that your body can make EFAs. However, the Mead acid acts as a "filler" fatty acid that cannot serve the functions that the original EFA are needed for. Peat claims that Mead acid has a full spectrum of protective anti-inflammatory effects; however, the body cannot convert Mead acid into the elongated fatty acids that the body needs for making the various anti-inflammatory prostaglandins.

Peat also asserts that polyunsaturated fatty acids become rancid in our bodies. This is not true; the polyunsaturated fatty acids in our cell membranes go through different stages of controlled oxidation. To say that these fatty acids become "rancid" is misleading. Of course, EFAs can become rancid through high temperature processing and it is not healthy to consume these types of fats. But the EFAs that we take in through fresh, unprocessed food are not rancid and do not become rancid in the body. In small amounts, they are essential for good health. In large amounts, they can pose health problems which is why we need to avoid all the commercial vegetable oils containing high levels of polyunsaturates.

Peat’s reasoning has led him to claim that cod liver oil causes cancer because cod liver oil contains polyunsaturated fatty acids. Actually, the main fatty acid in cod liver oil is a monounsaturated fatty acid. The two main polyunsaturated fatty acids in cod liver oil are the elongated omega-3 fatty acids called EPA and DHA, which play many vital roles in the body and actually can help protect against cancer. Furthermore, cod liver oil is our best dietary source of vitamins A and D, which also protect us against cancer.

Actually, Peat’s argument that polyunsaturated fatty acids become harmful in the body and hence cause cancer simply does not make sense. It is impossible to avoid polyunsaturated fatty acids because they are in all foods.

EFAs are, however, harmful in large amounts and the many research papers cited by Peat showing immune problems, increased cancer and premature aging from feeding of polyunsaturates simply corroborate this fact. But Peat has taken studies indicating that large amounts of EFAs are bad for us (a now well-established fact) and used them to argue that we don’t need any at all.

Finally, it should be stressed that certain components of the diet actually reduce (but do not eliminate) our requirements for EFAs. The main one is saturated fatty acids which help us conserve EFAs and put them in the tissues where they belong. Some studies indicate that vitamin B6 can ameliorate the problems caused by EFA deficiency, possibly by helping us use them more efficiently.


This article appeared in Wise Traditions in Food, Farming and the Healing Arts, the quarterly magazine of the Weston A. Price Foundation, Spring 2005.

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Comments (15)Add Comment
written by Tatyana , Jun 24 2013
hi i have medical professional background. Before I red Dr Ray Pat article on polyunsaturated fats are toxic I used regularly flax seed oil in my salads and also I used high quality omega 3 fatty acids from Neways company. I used the amount recommended for good health. My blood type is "O" so flax seed oil was recommended for this blood type. But I did not feel good at all, I was constantly tired and had tightness around thyroid gland. Then after several years after I red Dr Raymod Peat article about toxicity of polyunsaturated oils I stopped to use the flax seed oil or omega 3 supplements and did not pass long, my thyroid symptoms disappeared. Since then after I read that 75% of the cloth in heart arteries is from polyunsaturated fats I actually start to eat saturated fats in my diet, coconut, ghee, sometimes lamb without removing fats from the meet. My energy level is excellent and memory better than ever.
written by Johnimos, May 05 2012
I do like a respect the WAPF. And I do not mean this in any disrespectful way at all, I am being since. But I do question all of the articles about cod liver oil that anyone from WAPF writes. Does WAPF have any finical gain from the Green Pastures brand of cod liver oil? I'm just skeptical. You never really know these days. Ray Peat isn't selling anything beside a few books.
written by Garden Girl, Apr 13 2012
I cut out as much EFA as possible in my diet to see what would happen. I have no more allergies, water retention gone, inflammation gone, tremors dissappeared (that started on cod liver oil). These symptoms were all compliments of cod liver oil, crispy nuts, pork fat, sprouted/soured grains. I feel better than ever now. And to boot, my kids say I look 10 years younger. Thank you Dr. Ray Peat (and Hans Selye)!
Food for Thought on "EFA"
written by Rob Turner, Oct 21 2011

Claiming that certain fatty acids are essential, a scientific approach would require showing what was wrong with the experiments that showed that they were not essential, and especially, those that showed that they were positively harmful. – “Unsaturated fatty acids: Nutritionally essential, or toxic?” by Ray Peat

The above quote really says it all. In an article by a PhD publicly refuting the scientific work of another PhD, please at least provide one or more scientific references to validate your opinions. The onus here is on Dr. Enig to prove why "EFA" have shown harmful in studies, why an intentional "EFA deficiency" proves beneficial in both human and animal studies, and finally to show why "EFA" are indeed essential. From what I read above, that simply isn't done.
Ray peat reccomends pig and chicken
written by Ramon, Dec 14 2010
I dont know what you guys mean but the amount of PUFA's in chicken and pig fat is miniscule at best and a few articles he promotes foods from both animals.
written by Ross Allen, Sep 25 2010
Hello EL66K. Do you have a few references to backup the claim that EFA deficiency is a deficiency of other nutrients?
Enig is missing the point
written by Jamison, Sep 10 2010
In Peat's articles he writes that if there really are "essential fatty acids" that we need to figure out the absolute minimum requirements and keep it to that level.
"EFA"s are unavoidable, even if one consumed coconut oil as their only source of calories they would still get traces amounts of these "EFA"s. From what I have read, only very very small amounts of these fatty acids are needed on a daily basis, on the order of half a gram or so. In the presence of an otherwise healthy diet, a gram or two a day of these fatty acids isn't likely to cause any health problems.

In addition, you can't compare normal coconut oil to fully hydrogenated coconut oil, because the hydrogenation process requires the use of the toxic metal Nickel. So any study trying to guage the effects of "EFA deficiency" using fully hydrogentated coconut oil needs to control for the toxic effects of Nickel on the health of the animal or human being tested upon.
written by Jonathan, Feb 25 2010
Matt Stone,
Where did you get the info that a lot of WAPF-ers do not have reduced rates of obesity, heart disease, and cancer?
written by EL66K, Feb 10 2010
"fact that Efa deciciency is really"* Sorry, I meant theory. I'll leave it there for now.
written by EL66K, Feb 10 2010
Yeah, it's a shame. Mary doesn't really bring much science in this article. Actually Peat doesn't say cod liver oil is all bad, and recognizes it's therapeutic value through vitamins, but it's place is not where you need to reduce inflamation and have adequate vitamins A and D. Even Price himself acknowledged cod liver oil should only be used in as small quantities as posible, because it could become pathogenic.

The fact that the supposed EFA deficiency is really a deficiency of other nutrients through an upregulation of the metabolism is still undisputed.
All About Balance
written by Matt Stone, Feb 10 2010

You're right. It is all about balance. That's what I'm getting at. But for a person with 12 times the normal tissue accumulation of AA, it takes very stringent restriction of dietary omega 6 to overcome that imbalance and get back to health. The WAPF, recommending bottomless amounts of organ meats, eggs, poultry fat, lard, and "crispy nuts" offers no solution to that imbalance. No one on earth can reduce their tissue concentration of AA eating large quantities of these foods and thus "be balanced."
EFA's and CEDS
written by Dayadog, Feb 07 2010
It is all about the balance folks. Look into CEDS (Clinical Endocannabinoid Deficiency Syndrome. EFA's break into endocannabinoids in the body and help bring our bodies into a homeostatic level...assuming the right balance is there.
Matt Stone
written by Matt Stone, Feb 01 2010
He avoided foods lowest in omega 6 and 3, which includes nuts, poultry skin, pork fat, and vegetable oil primarily - and also fatty fish.

Of course, these are staples of WAPF followers, and could very well be one reason why a lot of WAPF-ers come up short in their health pursuits (although, clearly with many benefits, but not reduced rates of obesity, heart disease, cancer, etc.).

The problem is that modern humans have massive cellular overload of omega 6. To counterbalance that imbalance, you'll make more headway by making a concentrated effort to minimize omega 6 in your diet.

It's not just about identifying the healthy diets Price witnessed, following one of them, and then living happily ever after. There are specific strategies that can be used to overturn specific imbalances.
written by Rachelle, Jan 27 2010
"It (omega-6) is found in virtually all foods"
So you avoided virtually all foods?
The science refutes the "EFA" notion.
written by HansSelyeWasCorrect, Dec 28 2009
The "EFA" claim was refuted at M.I.T. in the 1940s. See:

I decided to test the notion on myself, eating a diet devoid of "EFAs," except in unavoidable amounts. I've eaten a lot of cheese, coconut products, butter, dark chocolate (70% or more), etc. I have experienced only benefits, no "deficiency symptoms." Too bad Mary, who has contributed so much to exposed "junk science," is propagating it with regard to "EFAs," which can only do harm to you if you are healthy (omega 3s might act as chemotherapy if you already have cancer - that is another matter entirely).

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Last Updated on Tuesday, 09 June 2009 16:50