By Anthony Masters

Before I start I would like to illiterate that throughout my life I have always sought out opposing opinions and evidence with almost everything I study, I find this a fundamental learning process in human development and to help formulate my own personal beliefs. Now for years as a trainer I have promoted fish oil to clients, friends and family for its vast beneficial qualities towards human health. My opinions have now changed, I am now more cautious to the use of it, especially in the long term after recently reading a few interesting articles. I would personally use fish oil for fast fat loss goals, improve hormonal profile and to help rebalance the omega 3:6 ratio and nothing else. I promote a lot of Charles Poliquin supplements and protocols for their quality and effectiveness. But the use of fish oil I am a lot more careful with now as it suppresses the immune function which always worries me and in the long term can be hazardous to our body. This is why after you have read what is to come I can not stress anymore the importance of getting good quality fish oil and keeping it refrigerated. A lot of what is written here on is more of a summary of other peoples works and not mine. I simply want to raise a few questions that may make you think twice. Ask yourself these questions:

Are essential fatty acids really that essential?

Do heart healthy oils harm us?

Why is temperature and environment so important?

Here is a summary from the works of Rob Turner and Ray Peat to help you make up your own mind.

“Saturated fats are more abundant in the animal world and unsaturated fats predominate in the vegetable world and in fish. This has been a part of nature’s adaptation to the environment, and does not signify that a mistake was made in the creation of warm-blooded animals.” -Broda and Charlotte Barnes

Marketing Magic

“The image of “hard, white saturated coconut oil” isn’t relevant to the oil’s biological action, but the image of “sticky varnish-like easily oxidized unsaturated seed oils” is highly relevant to their toxicity.”-Ray Peat, PhD

There is much marketing momentum behind some fats, like fish oils and seed oils, so taking into account how financial interests play a role is important in what the public and what professionals believe as truth. Anyone who has a conflict of interest in the matter (a reason to gain financially) should not be trusted on the matter – think Charles Poliquin and Udo Erasmus.


Dietary fats come in three different structures predominantly – saturated, monounsaturated, and polyunsaturated. Each dietary fat is actually a combination of all three of these structures. For example, 100% saturated fats don’t exist but rather a saturated fat will contain mostly saturated fat as well as smaller amounts of monounsaturated fat and polyunsaturated fat.

Saturated fats are very stable and remain solid at room temperature and below while turning into liquid above room temperature (they are liquid at human body temperature). Saturated fats do not contain any double bonds between carbon atoms like those seen in their unsaturated counterparts. The carbon atoms of saturated fats are saturated with single bonds to hydrogen atoms; the carbon atoms have the maximum amount of hydrogen atoms. This means that oxygen, light, or temperature does not easily break these bonds apart and change them. Saturated fats are non reactive.

Monounsaturated fats (MUFA) are liquid at room temperature and become cloudy in the refrigerator. MUFA have one (“mono”) double carbon bond and are relatively stable but this double bond can be affected by oxygen, temperature, and light over time which contributes to MUFA’s instability. This single double bond is susceptible to being modified and broken down. The single bond also manipulates the structure of the fat and creates a “kink” or bend.

Polyunsaturated fats (PUFA) are liquid at any temperature above freezing, are highly reactive, spoil quickly, & have two or more (”poly”) open double carbon bonds. PUFA are the most unstable of the three types of fats.

Because PUFA have multiple double bonds, they also have multiple kinks or bends in their structure. Oxygen, light, and temperature can easily break these fats apart at the site of the double bonds and create free radicals (lipid peroxides) that destroy important enzymes and damage vital energy producing cell structures. You cannot digest foods, dissolve blood clots, or release your thyroid hormone without enzymes. By reacting with oxygen, PUFA promote harmful oxidation while interfering with the productive use of oxygen.

Nature’s Examples

“Over the years, it has become evident that the polyunsaturated fats are not very compatible with a high rate of metabolism, though they are necessary for organisms that live at low temperatures and metabolise slowly, such as fish and vegetables. The saturated fats solidify at low temperature; beef fat is very stiff at refrigerator temperature, and in a fat fish, such stiffness would be lethal.” -Ray Peat, PhD

Many fish live in waters near freezing temperatures and are required to have liquid fats (polyunsaturated fats). Butter in your refrigerator hardens because it’s mostly saturated. This difference between the fats of a fish and the fats of cow’s milk from which butter is derived is explained by their different structures.

It’s these structural differences that we need to pay close attention to when making dietary choices. There are examples in nature that make things the picture clear. For example, if a fish had predominantly saturated fats in its tissues, it would have hardened fat and wouldn’t be able to move through cold water. Seeds exposed to cold temperatures have mostly PUFA in their tissues for similar reasons.

“The other reason is that the seeds are designed to germinate in early spring, so their energy stores must be accessible when the temperatures are cool, and they normally don’t have to remain viable through the hot summer months. Unsaturated oils are liquid when they are cold, and this is necessary for any organism that lives at low temperatures. For example, fish in cold water would be stiff if they contained saturated fats. These oils easily get rancid (spontaneously oxidizing) when they are warm and exposed to oxygen. Seeds contain a small amount of vitamin E to delay rancidity. When the oils are stored in our tissues, they are much warmer, and more directly exposed to oxygen, than they would be in the seeds, and so their tendency to oxidize is very great. These oxidative processes can damage enzymes and other parts of cells, and especially their ability to produce energy.” -Ray Peat, PhD

“The fact that saturated fats are dominant in tropical plants and in warm-blooded animals relates to the stability of these oils at high temperatures. Coconut oil which had been stored at room temperature for a year was found to have no measurable rancidity. Since growing coconuts often experience temperatures around 100 degrees Fahrenheit, ordinary room temperature isn’t an oxidative challenge. Fish oil or safflower oil, though, can’t be stored long at room temperature, and at 98 degrees F the spontaneous oxidation is very fast.” -Ray Peat, PhD

Just as liquid oils are necessary for organisms that can’t regulate their temperature but live at cold temperatures, saturated fats are necessary for organisms that live at high temperature or have a warm body temperature. For example, coconuts grow in tropical environments with temperatures that mimic the human body’s internal temperature (around 100 degrees). A predominance of liquid polyunsaturated fatty acids in a coconut’s tissues would quickly go rancid and breakdown at such temperatures just as they do when exposed to heat and oxygen in our body. Amazonian fish and soy beans living or growing respectively in hot temps have more saturated fat in their tissues relative to the same species living or growing in colder environments.

Saturated fats don’t work in cold-water fish; polyunsaturates don’t work in the high temperatures of the tropics. We should learn from natures’ examples. The organism’s exposure to oxygen, body temperature, and/or environment determine the fats which are ideal for the organism.

Since we are omnivorous, our consumption of polyunsaturates is reflected in our fat tissues. As we eat more polyunsaturates with ageing, these fats accumulate. It’s not to our advantage to eat foods containing large amounts of polyunsaturates or to refine these liquid oils, take them out of their intended environment, and introduce them into a place (i.e. our bodies) where they don’t belong. Our fats should be predominantly stable at warm temperatures (~98F/37C) and when exposed to oxygen, but when we consistently eat foods rich in polyunsaturates we violate this rule. The warm, oxygen-rich internal environment of humans isn’t the place for large amounts of reactive polyunsaturates.

Protective Saturated Fat

Non-reactive saturated fats are best for our physiology because they do not break down into toxic by products (lipid peroxides) like PUFA do in such an environment. It’s important to also note that when the body forms fats from carbohydrate, it does not form these unstable, toxic fats. This left the door open for some to believe in “essential fatty acids.”

An essential nutrient is a nutrient required for normal functioning that either cannot be synthesized by our body at all, or cannot be made in amounts adequate for good health, and thus must be obtained from a dietary source. It’s true that the body doesn’t synthesize the so called “essential fatty acids” (EFA). “EFA” and other PUFA are environmentally derived, but these fats are not needed for human health. The body doesn’t make these fats because they’re toxic, not because they’re essential. More discussion on that topic here and here.

Endogenously formed fats or saturated fats from the diet carry none of PUFA’s negatives effects. PUFA harm fetal and childhood development, immunity, mitochondrion health, thyroid function, and the activity of key enzyme involved in energy production called cytochrome oxidase . These fats also promote estrogen, development of age pigmentation, liver inflammation, heart damage, brain degeneration, slowed detoxification, and depressed longevity. PUFA are protectively found in seeds, nuts, beans, and above ground vegetables to inhibit the digestion of grazing animals except those which have developed a digestive physiology to overcome them (herbivores). Humans are omnivores.

Fish Oil

The fish oils are the most unsaturated fat (have the most double bonds) and pose many dangers for humans. EPA and DHA, polyunsaturated fats found in fish, have five and six double bonds respectively. EPA and DHA are ideal for cold waters, but your body temperature is far warmer and not suited for such fats.

Fish oils are exceptionally well-suited at suppressing immune function. They “reduce inflammation” in large part by destroying immunity much the way x-rays used to for inflammatory conditions. The use of x-rays to reduce inflammation in rheumatic sufferers brought about atrophy, fibrosis, and cancer. The massive use of fish oils will prove to do the same.

Fish oils do inhibit the production of prostaglandins by interfering with the conversion of linoleic acid into arachidonic acid making them anti-inflammatory in that way. Aspirin, vitamin E, and a PUFA-deficient diet produce similar effects without the suppressive effects on the immune system and thyroid. Fish oils are directly associated with Alzheimer’s. Saturated fats are protective against the disease.

Paints & Varnishes

“When exposed to air natural fatty acids having two or more double bonds tend to undergo a complex process called autooxidation, in which molecular oxygen attacks a double bond to yield a series of products which ultimately polymerize to form a hard resinous material. Linseed oil, used a base for paints, is rich in highly unsaturated fatty acids, and undergoes this polymerization process as it “dries.” Autoxidation of unsaturated fats in the tissues is also believed to occur in some disease.” -Albert Lehninger, PhD

It’s the formation of this resinous material that should make polyunsaturates garner more attention in discussions regarding heart disease.

Food marketers want the public to forget the liquid oils’ historic uses. Fish and seeds oils were previously used as paints/varnishes because of their propensity to react with oxygen (“autooxidation”) and stick to the canvas. When petroleum based paints came around, the market for fish and seed oils vanished because it’s cheaper to make paints/varnishes from oil. The clever seed and fish oil industries created a new market – the supermarket – capitalizing on the erroneous research saying the fats within these oils were essential, heart healthy, and/or lowered cholesterol.

The third reason is true (although it’s another toxic effect) and the first two reasons are false and prove harmful. This mega market for PUFA still exists today to the financial benefit of seed and fish oil manufacturers but to the detriment of human health. Don’t fall for the marketing.


Most processed/packaged food manufacturers and restaurants use polyunsaturated oils so make sure to check food labels. These oils are cheaper than safer options, like butter and coconut oil. When money is at stake, your health takes a back seat. Below is a list showing the major dietary sources of PUFA and saturated fat. Keep dietary fat consumption high in saturated fats and low in polyunsaturated fats.


These fats are liquid at refrigerator temperatures

  • Any nut, seed, bean, or vegetable oil
  • Soy oil
  • Sesame Oil
  • Peanut Oil
  • Wheat Germ Oil
  • Corn oil
  • Safflower oil
  • Cottonseed Oil
  • Canola Oil (used in cooking at Whole Foods Market)
  • Fish oil
  • Hempseed Oil
  • Grape Seed Oil
  • Flax Seed Oil/Linseed Oil
  • Walnut Oil
  • Almond Oil
  • Borage Oil
  • Evening Primrose Oil
  • Grains
  • Above ground vegetables
  • Beans
  • Nuts
  • Industrially fed poultry and pigs
  • “Omega 3″ or “Omega 6″ on labels

Saturated Fats – These fats are solid at refrigerator temperatures

  • Cocoa butter, chocolate (without soy lecithin)
  • (Refined) coconut oil
  • (Salted) Butter
  • Ghee
  • Dairy
  • Ruminant fat (buffalo, cow, goat, lamb, deer)
  • Pastured eggs
  • Pastured or wild animal fats

References: Articles: “The great fish oil experiment” and “Unsaturated fatty acids: nutritionally essential or toxic?

About Anthony

Anthony has been in the fitness industry for over 16 years. In the early years competing as a semi-pro tennis player touring internationally on the ITF circuit, later in life exploring the practices of CrossFit, rock climbing, snowboarding, Olympic weightlifting and triathlons. In order to improve his knowledge and better himself as a trainer for his clients he has continued to research vast subjects, getting into official and unofficial studies of anatomy, physiology, psychology, bio-mechanics, training methodology, nutrition, sports and mind-body practices.

Anthony Masters is a Personal Trainer at MoreFit St Paul’s. Having worked with clients with a variety of goals ranging from stress reduction, fat loss, rehabilitation, strength training, pre/ post natal, endurance and sport specific training he is confident to tailor a specific training program to the clients individual needs. Making every session different, challenging and fun, Anthony’s motto is “you give him 100% and he will give you 110% back” as your success is his success!