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Cod Liver Oil - #1 Super Food

Updated: May 24, 2022

As you may know, I am writing a book titled, "Health Freedom Lost." I am working on a chapter titled, "Under-appreciated Nutrients." If you know me even a little bit, I am either talking about gaussian curves or cod liver oil. For all of you who loathe math, this is your lucky day because cod liver oil is the subject.

Hopefully you will read this but also be aware that this is completely unedited at this time. I appreciate any comments you might have. You can write to me at

The section in my upcoming book......


Note - It says "Pleasant to the Taste"

Cod Liver Oil

Cod liver oil is the most important superfood you should take daily and no, it is not disgusting to do so. Just do some root-cause analysis on your preconceived notions. Why do you think cod liver oil is repulsive? Is it the odor, taste, texture, past experiences, or a combination of all of these factors?

There is no sense in talking about the benefits of CLO and other liver foods is you will not consume them. Europeans eat much greater amounts of organ meats compared to United States citizens. They also live longer - by 2.5 years on average - and pay only 40 percent of what Americans pay for healthcare.

Here is how I got over my repugnance of beef liver. My objection was: taste, texture, and the odor of liver and onions that my mother made for my dad. solved each of these by making pate. Here is my recipe:

· fresh grass-fed beef liver ~1/4 pound, sliced into small pieces

· fresh vegetables of all types, sliced and chopped ~3/4 pound. I use whatever is available at the time.

· In a sauce pan with butter, add all the ingredients and simmer on low heat for about 30 minutes, covered. Add as many spices as you like. Sage, turmeric, oregano, salt, pepper, ginger, and a Braggs sea salt seasoning are my usual.

· Toward the end of the simmering, add coconut milk for some additional liquid necessary to create the right consistency of the pate.

· Let the mix cool and then blend in a food processor. Add more coconut milk, as needed, to create a consistency similar to hummus.

The pate made this way freezes and thaws well. Add something like salsa or other favorite food when you serve this. All objections are easily overcome, and you get a highly nutritious meal at low cost that is easy to prepare

The objections to cod liver oil (CLO) are even easier to overcome. Start with the liquid version and there are several high-quality brands available. Have a meal, preferably dinner. Consider pate. Right after dinner, fill 1/2 of a shot glass full of cod liver oil liquid. This is about 15 grams. This is the minimum amount you want to combat serious diseases like arthritis, Alzheimer's, and eye diseases. Next, "shoot" the CLO and chase it with something acidic. The CLO is chemically basic so taking in a little acid quickly neutralizes the flavor and texture objection to taking it. My preferred is dilute apple cider vinegar, kombucha, some other type of fermented beverage, or a slice of grapefruit.

My personal favorite CLO image

Today, we need to count our blessings because over 100 years ago, cod liver oil was much less palatable. The man with a fish on his back was the decal on cod liver oil bottles back in the day and it is the name of an article describing the history of cod liver oil.[1] In that article the early manufacture of cod liver oil was described as, "cut out the fish livers with gallbladders, throw them into barrels, and let them decompose. Fishermen often applied het to extract the last bits of oil from the smelly, decaying mass." In that article, reference was made to a pharmacist who wrote, “cod-liver oil was not a desirable article of consumption; indeed, to put the matter plainly, it was an abomination, and no one could have taken it willingly, even once, not to speak of day after day and month after month. Nevertheless, many people did take it, and the only reasonable explanation is that the oil must have given strikingly favorable results.”

The method of "chasing" the cod liver oil with something more palatable is almost as ancient as cod liver oil itself. Some early ideas for taking this elixir included:

· mixing a little preserve for children, some fruit, a biscuit, or a drop of Bordeaux or Sherry wine,

· mixing into coffee, milk, or brandy,

· taking the oil with smoked herring, tomato ketchup, or in the froth of malted beverages, and

· for those with an “insurmountable aversion to the taste” could take the oil by enema.

We have it good today with the highly refined and purified versions of cod liver oil widely available. Coffee enemas are often used for gut cleansing. Consider adding a little cod liver oil to your coffee enemas. Ok, may this is going a bit too far.

The liver of any animal is the warehouse for the raw materials needed to rebuilt tissue. According to the Hepatitis C Trust website,[2] "The liver acts as a storage site for some vitamins, minerals and glucose. These provide a vital source of energy for the body which the liver transforms into glycogen for more efficient storage. The liver stores vitamins and minerals for the times when they may be lacking in the diet. It can store enough vitamin A and vitamin B12 for four years, and enough vitamin D for four months."

Johns Hopkins School of Medicine has this to say about the liver.[3] "The liver regulates most chemical levels in the blood and excretes a product called bile. This helps carry away waste products from the liver. All the blood leaving the stomach and intestines passes through the liver. The liver processes this blood and breaks down, balances, and creates the nutrients and also metabolizes drugs into forms that are easier to use for the rest of the body. More than 500 vital functions have been identified with the liver. Some of the more well-known functions include the following:

· Production of bile, which helps carry away waste and break down fats in the small intestine during digestion

· Production of certain proteins for blood plasma

· Production of cholesterol and special proteins to help carry fats through the body

· Conversion of excess glucose into glycogen for storage (glycogen can later be converted back to glucose for energy) and to balance and make glucose as needed

· Regulation of blood levels of amino acids, which form the building blocks of proteins

· Processing of hemoglobin for use of its iron content (the liver stores iron)

· Conversion of poisonous ammonia to urea (urea is an end product of protein metabolism and is excreted in the urine)

· Clearing the blood of drugs and other poisonous substances

· Regulating blood clotting

· Resisting infections by making immune factors and removing bacteria from the bloodstream

· Clearance of bilirubin, also from red blood cells. If there is an accumulation of bilirubin, the skin and eyes turn yellow.

In general, land animal liver is rich in water soluble nutrients while CLO and other marine animal livers tend to be higher in fat soluble nutrients.

Staying healthy is all about taking in sufficient quantities of micronutrients. Liver, as a food, is at the top of the nutrient density list according to Harvard nutrient guru, Dr. Mat Lelonde. It makes sense when you look at how nutrients pass from the soil to foods. The soils provide the micronutrients necessary to build plants. The soil is the "gut" of the plant and the gut of animals is their "soil." Here is the process:

1. Soil contains minerals and other micronutrients.

2. Plant requires minerals and micronutrients to grow (photosynthesis). Roots absorb nutrients and water from the soil. Plants also deliver substances to the soil to help break it down to become more bio absorbable.

3. Plant is mostly carbohydrate but has the micronutrients used to build its structure. The plant also synthesizes certain vitamins.[4]

4. Animals eat the plants

5. Human, particularly Americans, eat the muscle meat of animals

6. Most of the important micronutrients are concentrated in the liver and other organs, not the muscle meat.

7. Americans have the worse health when compared to other developed nations.

That is why this chapter begins with ways to consume more liver. Vegans can hate on this concept but our large brains are due to cooking and an omnivore style of eating. Proof, with an "n" of 1 is Michael Greger.

Cod liver oil gained its popularity not as a snake oil, but as a true medicinal. Historically, cod liver oil contributed to the resolution of serious diseases.

· Arthritis, dating back to the Viking era where topical and internal intake improved the condition,

· Tuberculosis, in the 1800s reduced mortality by 50%, and

· Rickets, a rampant disease around the turn of the 19th century, was all but eliminated by taking cod liver oil.

Resolution of Rickets is the reason your grandmother or great grandmother gave you cod liver oil when you were a youth.

In modern times, strong evidence-based studies show that taking cod liver oil improve many chronic conditions while enhancing overall health. Poignant examples include reduction of early childhood mortality, blindness, and increasing IQ. It can help resolve these varied problems because, at their root, is substantial commonality. The fat-soluble vitamins in cod liver oil have immune enhancing anti-inflammatory and antibiotic properties.

The Brain

The omega-3 components of cod liver and fish oils have a profound impact on brain wiring. The "3" of omega-3 fatty acids refers to the location of "unsaturation" in the long-chain fatty acid. The unsaturated part of the fatty acid chain is the reactive part of that molecule’s backbone. The "6" of omega-6 fatty acid means that the "unsaturation" occurs at a different place along the fatty acid chain. The seemingly slight difference has major consequences to brain function. Most of the publications on fish oils and brain health are not very scientific. Here are a couple of technical paragraphs that explain how important these omega-3 fats are to brain health and why with some editing performed to make it more understandable.[5]

"Omega-3 fatty acids have the potential to influence neurogenesis (growth of new brain cells) through at least two distinct mechanisms. First, omega-3 fatty acids are incorporated into neuronal membranes, where they influence the structure of membrane proteins, some of which act as transporters and receptors. They also can alter membrane fluidity, which is important for neurotransmitter binding as well as signaling within cells. For instance, lipid fluidity modulates the binding of serotonin to neuronal membranes. As serotonin stimulates neurogenesis a change in efficacy of this modulator could influence the levels of neuronal proliferation (replication and expansion). Therefore, omega-3 fatty acids may alter (enhance) the rate of neurogenesis via their contributions to the dynamic structure and function of neuronal membranes.

"A second potential pathway by which these omega-3 fats may influence neurogenesis is by enhancing immune function. For example, EPA inhibits the release of inflammatory substances. Omega-3 fatty acids also influence levels of neurotrophins, molecules that promote neuronal survival and growth. Neurotrophins associated with improvement in neurogenesis and neuronal survival."

"These connections between the omega-3 fatty acids, inflammation, neurotrophins and neurogenesis are also intriguing from the clinical perspective. Inflammation appears to play a potentially critical role in depressive illness. Stress can cause an elevation in inflammation. Therefore, the same molecules that are of importance in regulating neurogenesis, also are implicated in major depressive illness. Although there are not adequate data at this time to make a conclusive statement regarding the functional relationship between neurogenesis and clinical depression, these associations are suggestive of pathways by which omega-3 fatty acids may simultaneously influence neurogenesis and depressive illnesses."

A remarkable benefit of taking fish oil and cod liver oil, in particular, is its impact on mood. Prison populations arguably are people with mood issues that are greater than the general population. And, in some countries, they are accessible people to study as long as the intervention is a "do no harm." There is evidence that prisoners consume diets lacking in essential nutrients and this could adversely affect their behavior. As processed foods, low in nutrient density, have become more heavily consumed, many members of society, not just the prison population, experience substantial brain-related ailments.

One study on prisoners and essential fatty acids is titled, "Influence of supplementary vitamins, minerals and essential fatty acids on the antisocial behaviour of young adult prisoners: Randomised, placebo-controlled trial."[6] According to the authors, "Both omega-6 and omega-3 essential fatty acids have been found to be deficient among violent offenders.[7] For this reason, an essential fatty acid supplement was also employed. ‘Efamol Marine’ provides omega-6 and omega-3 essential fatty acids without an obvious after-taste, a factor that could otherwise have compromised the blind. The daily dosage was four capsules providing 1260 mg linoleic acid, 160 mg gamma linolenic acid, 80 mg eicosapentaenoic acid and 44 mg docosahexaenoic acid. A vegetable oil-based placebo of identical colour and clear placebo of identical colour and clear gelatine shell was used."

The authors concluded, "This research strongly suggests that the effect of diet on antisocial behaviour has been underestimated and more attention should be paid to offenders’ diets. It should should be paid to offenders’ diets. It should be noted, however, that the current dietary standards by which dietary adequacy are standards by which dietary adequacy are judged barely take behaviour into account. Thus, having demonstrated empirically an effect on antisocial behaviour, we are only effect on antisocial behaviour, we are only at the start of understanding the potential of this intervention."

The Guardian magazine looked at the link between junk food and violence in an article written in 2006. It is titled, Omega-3, junk food and the link between violence and what we eat.[8] Here is a most interesting quote from the article.

"That Dwight Demar is able to sit in front of us, sober, calm, and employed, is "a miracle", he declares in the cadences of a prayer-meeting sinner. He has been rocking his 6ft 2in bulk to and fro while delivering a confessional account of his past into the middle distance. He wants us to know what has saved him after 20 years on the streets: "My dome is working. They gave me some kind of pill and I changed. Me, myself and I, I changed."

"Demar has been in and out of prison so many times he has lost count of his convictions. "Being drunk, being disorderly, trespass, assault and battery; you name it, I did it. How many times I been in jail? I don't know, I was locked up so much it was my second home."

Demar has been taking part in a clinical trial at the US government's National Institutes for Health, near Washington. The study is investigating the effects of omega-3 fatty acid supplements on the brain, and the pills that have affected Demar's "miracle" are doses of fish oil."


Tuberculosis is a serious and often fatal lung disease caused by the bacterium, tubercule baccilum. Late stage deadly tuberculosis infection is called "consumption." The name "consumption" was used to describe the disease because it "consumed" the lungs. In the 1800s consumption had killed one in seven of all people that had ever lived. It was initially thought to be a disease of genetics and many consumptive patients pursued relief in sanatoriums alongside leprosy patients. The belief was that rest and a healthful climate could change the course of the disease while the actual benefit included vitamin D production on the skin at the high altitudes where UV exposure is higher compared to sea level.

In 1882, Robert Koch's discovery of the tubercule baccilum revealed that TB was infectious and highly contagious and was somewhat preventable through proper hygiene. As is usually the case with a new discovery, the medical community was slow to accept Koch's findings as death mounted. This continues to be a recurring story.

According to the Mayo Clinic TB, which should be completely eradicated, has made a comeback in the modern era.[9]

"Tuberculosis (TB) is a potentially serious infectious disease that mainly affects the lungs. The bacteria that cause tuberculosis are spread from person to person through tiny droplets released into the air via coughs and sneezes.

Once rare in developed countries, tuberculosis infections began increasing in 1985, partly because of the emergence of HIV, the virus that causes AIDS. HIV weakens a person's immune system, so it can't fight the TB germs. In the United States, because of stronger control programs, tuberculosis began to decrease again in 1993. But it remains a concern.

Many tuberculosis strains resist the drugs most used to treat the disease. People with active tuberculosis must take many types of medications for months to get rid of the infection and prevent antibiotic resistance."

Cod liver oil, with its natural mixture of vitamins A and D is a treatment for TB. Since TB is a highly virulent pathogen, cod liver oil is not a cure, but significantly reduces both morbidly and mortality from the bacterium. In the study, carried out by physicians at the Hospital for Consumption, 542 patients with consumption (tuberculosis) received standard treatment with cod liver oil. These patients were compared with 535 ‘control’ patients who received standard treatment alone (without cod liver oil).[10] The disease stabilized in 18% of the patients given cod liver oil compared with only 6% of those in the control group. Deterioration or death occurred in 33% of patients given standard treatment alone, but in only 19% of those given cod liver oil, an absolute reduction of 14%. Today the benefit of most drugs are given in relative statistics, so, for the sake of comparison, the relative reduction in deaths on cod liver oil was 74%. Using either statistic, the improvement in health was impressive.

Do you have asthma, COPD, a chronic cough or other lung issue? If so, take high doses of cod liver oil. Do you want to live a long healthy life with an alert mind? If so, take high doses of cod liver oil. The right dose matters, however. When a drug company studies a new pharmaceutical, billions are spent on its approval. A substantial portion of those funds look at dosing studies to find the level of the drug that provides the greatest statistical benefit. Many studies on fish oils, including cod liver oil, use an unscientific dose of 1 gram and when the results a paltry, the conclusion is fish oil provides no benefit. The TB study of the 19th century provides the proper dose based on the admiral outcomes. The 542 inpatients with consumption treated with cod liver oil, were given a dose of 1 drachm (3.6 ml) three times a day, gradually increased, in some few cases up to 1.5 ounces (42 ml) per dose.

The proper dose, based on this British study on tuberculosis is:

Healthy people for health maintenance: 10 grams/day (2 teaspoons). This is equivalent to the lowest dose given to consumption patients - 3.6 ml (approximately 3.6 gram) three times per day. For people with any type of lung issue, up to 120 grams per day (42 ml three times per day) is recommended

Indeed, 120 grams per day is quite a lot of cod liver oil, but it sure beats having a chronic lung problem. This dose may provide too much vitamin A. Dr. Trempe recommended 15 grams per day for people with glaucoma or macular degeneration and sometimes started these patients on 30 grams per day for the first month and then had them reduce the dose to 15 grams/day.


The disease called Rickets, a painful disease of the bone, cured by cod liver oil, provides evidence that bone health is not just about calcium. Rickets is a disease of vitamin D deficiency, and is thought to be rarely seen today, however it is still a ubiquitous condition. At the turn of the 20th century rickets was particularly rampant among the poor children living in industrialized and northern cities globally. Lack of exposure to sunshine was the cause and was and continues to be especially noted in people with high levels of skin pigmentation.

The popular belief is that rickets is just a bone or skeletal disease, easily fixed with vitamin D supplementation. However, there is also an extra skeletal component to Rickets that is deadly, while the skeletal component is debilitating. This extra skeletal feature includes seizures caused by a general lack of calcium absorption and a decrease in neurotransmitter release and muscle contraction facilitated by calcium. The other manifestation is cardiomyopathy which is s a disease of the heart muscle that makes it harder for the heart to pump blood to the rest of the body. Cardiomyopathy can lead to heart failure.

"A Brief History of Nutritional Rickets" explains how vitamin D deficiency causes the heart and muscle problems. The key points made in the article include:

· An adequate serum concentration of Vitamin D is required for optimal absorption of calcium from the gastrointestinal tract.

· This vitamin D concentration or status is maintained by either production following ultraviolet B (UVB) irradiation of the skin, or

· By supplementation/fortification as diet alone is unlikely to meet normal daily requirements.

· When Vitamin D deficiency occurs, calcium absorption is reduced and furthermore when accompanied by low dietary calcium intake can lead to total body calcium deficiency and compensatory hyperparathyroidism.

· Elevated parathyroid hormone concentrations results in low serum phosphate levels with resultant abnormal bone mineralization.

· Rickets is specific to children due to their open growth plates and results from a combination of poor mineralization.

· There are multiple causes of rickets, but vitamin D deficiency, usually in concert with dietary calcium deficiency, is the leading cause with an incidence.

· As calcium is essential for normal nerve and muscle function, low serum calcium can result in neuromuscular excitability which in severe cases can result i convulsions.

· Low calcium muscle problems can also manifest in cardiac problems and lead rarely to death.

Cod liver oil is a superior form of vitamin D supplementation for Ricket prevention and for obtaining sufficient blood vitamin D levels. Vitamin D found in cod liver oil is similar to that made by photosynthesis on your skin and includes up to six different forms, not just vitamin D3. The exact nature of vitamin D in cod liver oil remains a mystery. Vitamin D supplements contain solely 25-hydroxyvitamin D. This version is actually considered an inactive form of vitamin D. However, it is converted to the active form, 1,25-dihydroxyvitamin D in the liver. Cod liver oil is reported to have some of the active form of vitamin D - again, not found in supplements. The active form of vitamin D in cod liver oil is available because the liver and kidneys of the cod fish possesses the enzymes that converts the inactive form to the active form. In some respects, the vitamin D from cod liver oil may be better than that produced on your skin because the cod liver carries out the conversion for you.

Harvard Medical School published an article titled, "Vitamin D and your health: Breaking old rules, raising new hopes."[11] Here are some key excerpts from that article.

· "Although vitamin D is firmly enshrined as one of the four fat-soluble vitamins, it is not technically a vitamin. True, it's essential for health, and only minuscule amounts are required. But it breaks the other rules for vitamins because it's produced in the human body, it's absent from all natural foods except fish and egg yolks, and even when it's obtained from foods, it must be transformed by the body before it can do any good."

· "Vitamin D is not one chemical but many. The natural type is produced in the skin from a universally present form of cholesterol, 7-dehydrocholesterol. Sunlight is the key: Its ultraviolet B (UVB) energy converts the precursor to vitamin D3. In contrast, most dietary supplements are manufactured by exposing a plant sterol to ultraviolet energy, thus producing vitamin D2. Because their function is almost identical, D2 and D3 are lumped together under the name vitamin D — but neither will function until the body works its magic."

· "The first stop is in the liver, where vitamin D picks up extra oxygen and hydrogen molecules to become 25-hydroxyvitamin D, or 25(OH)D. This is the chemical that doctors usually measure to diagnose vitamin D deficiencies. But although 25(OH)D is used for diagnosis, it can't function until it travels to the kidney. There it acquires a final pair of oxygen and hydrogen molecules to become 1,25 dihydroxy vitamin D; scientists know this active form of the vitamin as 1,25(OH)2D, or calcitriol, but for ordinary folks the name vitamin D is accurate enough."

· "It used to be simple: just get a "healthy" tan and your body will make all the vitamin D it needs. Desk jobs and sunscreen have changed all that, just as research is underlining the importance of vitamin D and suggesting its possible role in preventing many health problems. That makes vitamin D a dilemma of modern life that has a modern solution: eating fish and drinking some low-fat fortified milk, along with judicious doses of vitamin D supplements."

Ugh! Typical of Harvard to get most of it right then revert back into an old misinformed dogma. Drinking some low-fat fortified milk? Really? Dr. Trempe was a member of Harvard Medical School staff for 47 years and he knew the right way to get vitamin D. He was recommending 15 grams of cod liver oil daily in the 1980s.

Eyes and Childhood Mortality

Dr. Alfred Sommers is an ophthalmologist, as is Dr. Trempe. They know something most of the rest of us do not know about the retina and vitamin A. Vitamin A is a mixture of retinal and retinol. Eye doctors study and treat the retina. Is there a coincidence in the similarity of the names?

Retina definition: "innermost coating of the back of the eyeball;" from Medieval Latin retina "the retina," probably from Vulgar Latin (tunica) retina, literally "net-like tunic," on resemblance to the network of blood vessels at the back of the eye, and ultimately from Latin rete "net."

Vitamin A is a mixture, most commonly associated with beta carotene. However, its true composition is a group of organic compounds that includes retinol, retinal (also known as retinaldehyde), retinoic acid, and several provitamin A carotenoids, most notably, but not exclusively, beta-carotene. Vitamin A deficiencies have specifically been linked to blindness, which is how the discovery of these retinoids came about. Ancient Egyptian, Ancient Greek and medieval medicine have all shown evidence of using animal liver, where vitamin A is most abundant, treats night blindness. Thus, vitamin A was named after the retina.

The story of Dr. Sommers and vitamin A is quite remarkable. In general, everyone should obtain their vitamin A through cod liver oil because it is a food that contains many other important fat-soluble nutrients, many or all of which support the action of vitamin A and vitamin D. Yes, cod liver oil today is processed but so is every supplement you obtain is pill, liquid, or capsule form. If you want the best cod liver oil, obtain cod livers rather than the supplement.

Here is Dr. Sommer's story as told by his institution, Johns Hopkins School of Public Health. The article is titled, " The Story of Dean Sommer and Vitamin A."[12]

"The landmark work on vitamin A by Alfred Sommer, MD, MHS, dean emeritus of the School of Public Health, has been credited with saving the lives of millions of children around the world. In 1976, Dr. Sommer, who had just finished his residency in ophthalmology at Johns Hopkins' Wilmer Institute, began a series of complex intervention trials in Indonesia that revealed that even mild vitamin A deficiency (VAD) dramatically increases childhood mortality rates, primarily because VAD reduces resistance to infectious diseases such as measles and diarrhea.

In fact, the survival of children randomized to vitamin A was so much greater than that of children not receiving vitamin A, that many scientists considered the study flawed, and the results too good to be true. Before Sommer undertook these studies, scientists knew that VAD could lead to blindness; they were unaware, however, that a vitamin A-deficient child faces a 25 percent greater risk of dying from a range of childhood ailments such as measles, malaria, or diarrhea. As a result of his research, night blindness is today viewed not as a mild, early sign of VAD, but as evidence of late, severe deficiency.

To definitively prove the link between even mild VAD and pediatric mortality, Sommer and his colleagues ran a number of large-scale, community-based, randomized trials from 1983 through 1992. Keith West, PhD, professor, International Health and Ophthalmology, Joanne Katz, ScD, professor, International Health, and James Tielch, PhD, professor, International Health, among others still at the School, all played major roles.

Their work showed that ensuring adequate vitamin A intake can mitigate the effects of common diseases such as measles and diarrhea; reduce child mortality in at-risk populations by 23 to 34 percent to avert up to one million deaths a year; and prevent as many as 400,000 cases of childhood blindness each year. By 1992 the World Health Organization (WHO), UNICEF, the Food and Agriculture Organization of the United Nations, and the Convention on the Rights of Children had all declared the control of VAD a global goal.

Sommer and his team then set themselves the task of demonstrating that oral, high-dose, vitamin A supplementation—a treatment tailor-made for developing countries since it does not require a sterile injectable preparation—could effectively, quickly, and cheaply treat the debilitating consequences of VAD. As a result, the World Development Report (World Bank) declared vitamin A supplementation one of the most cost-effective of all health interventions.

With vitamin A capsules costing only 2 to 3 cents each, increasing vitamin A intake is now recognized as one of the most cost-effective public health interventions for child survival. The full cost of delivering the capsules to children ages six months to five years at six-month intervals is about 50 cents per child per year. Moreover, a World Bank study estimates that for every dollar invested in supplementation, more than $100 would be returned in increased productivity associated with reduced childhood mortality, lower health care costs, and improved worker performance.

In 1995, out of 72 countries where VAD was prevalent, only six had adequate vitamin A supplementation rates. In 1998, the year WHO and its major partners launched the Vitamin A Global Initiative, vitamin A supplements were delivered through national immunization days to more than 12 million vitamin A-deficient children in 40 countries.

Today, thanks in large part to Dr. Sommer's work, more than 40 countries are reaching the large majority of their children with at least one high-dose vitamin A supplement a year. UNICEF estimates that between 1998 and 2000 as many as 1 million child deaths may have been prevented because of this global vitamin A supplementation program. The most recent studies by Dr. Sommer and his colleagues have shown that supplementing women of childbearing age with vitamin A or beta-carotene reduces maternal mortality by an average of 45 percent, by improving their resistance to infection and reducing anemia."

In the 1800s in the United States, up to 30% of children died before their first birthday, and 43% did not survive past their fifth birthday. If the child lived to ten, they still only had a 60% chance of surviving to adulthood. A small sampling of our death records illustrates the common causes of death among children - consumption (tuberculosis), croup, whooping cough, smallpox, measles, cholera, typhus, typhoid fever, diphtheria, influenza, and scarlet fever - all infectious. These are the types of conditions contributing to blindness and early childhood mortality that Dr. Sommers confronted head-on with vitamin A.

The important takeaway from this work is that vitamin A, the mixture, is a highly effective antibiotic. Early childhood blindness, and the major eye diseases today are infectious diseases that vitamin A can help prevent and treat. However, cod liver oil which is rich in vitamin A has many other health-promoting substances making it the preferred source of vitamin A.

Brief History of Cod Liver Oil

The history of cod liver oil explains much about what we need to know about the benefits of cod liver oil, its production and dosage. An article titled, "What the History of Cod Liver Oil Teaches Us About Omega-3 Potency"[13] produces an excellent summary and is reproduced here. It was written by Bo Martinsen, MD, an omega-3 specialist, innovator, and advocate for natural foods

"In 1937, surgeon M. B. Daver noticed something odd while using cod liver oil to treat burns and pus-filled sores. “Crude” cod liver oil helped his patients heal quickly. But refined cod liver oil did not have the same wound healing benefits. Did the refining process destroy the properties that made cod liver oil effective, Daver wondered in a British Medical Journal memorandum.

Eighty years later, Daver’s question is increasingly relevant. Omega-3s have evolved into a $4 billion industry, including everything from natural liquid fish oils to refined prescription pills. These products differ wildly in their nutrient profiles, dosages and even chemical makeups. Yet, they all usually get lumped together in reviews of omega-3 supplements.

Such generalizations make it confusing to read nutrition news. One week, headlines declare that fish oils have no heart health benefits and may even increase the risk of atrial fibrillation. The next week, studies show omega-3s fight cancer tumors. How can we make sense of the conflicting findings? To get a better understanding, let’s take a closer look at fish oil’s long history and how today’s refining trends affect fish oil benefits.

Fish liver oil has a long history of medicinal use. In ancient Greece, Hippocrates (the so-called “Father of Medicine”) described using dolphin liver oil to treat skin issues. The Vikings prized fish liver oil as “the gold of the ocean,” thanks to its healing properties. Cod liver oil remained a popular folk remedy in Northern Europe for centuries. And as early as 1782, English physicians began studying cod liver oil and prescribing it for rheumatism. During the 19th century, cod liver oil became a widely accepted treatment for rickets, tuberculosis, joint and muscle pain, and skin wounds.

Though cod liver oil was popular, 19th century scientists didn’t understand why it worked. Did cod liver oil contain some special, unknown ingredients? Or, were components working together to deliver synergistic benefits? In the 1910s, biochemists thought they found the answer when they discovered two essential nutrients in cod liver oil: vitamins A and D. Soon, scientists began extracting these vitamins from cod liver oil, believing them to be the sole reason for the oil’s potent effects. In the 1940s, however, scientists began to wonder if cod liver oil offered something else besides vitamins. After all, in rat studies, other oils containing even more vitamin A and D didn’t prove as effective as cod liver oil.

In the early 1970s, researchers Bang and Dyerberg seemed to uncover the missing puzzle piece. They determined that fish and fish oil contained two omega-3 fatty acids called eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Since their discovery, EPA and DHA have become some of the best studied nutrients in history, with over 30,000 scientific papers to their names. EPA and DHA have been researched for everything from heart disease to rheumatoid arthritis. Scientists have also learned that these fatty acids reduce inflammation, support healthy nutrient exchange, and influence gene expression.

While EPA and DHA are vitally important, they represent just two members of a much larger fatty acid family found in fish and fish oil. Most of these other fatty acids haven’t been extensively researched yet. However, initial studies indicate they have potent benefits, too. These findings suggest that EPA and DHA may just be part of fish oil’s evolving nutrition story, much like vitamin A and D were one century ago. A big fatty-acid family: EPA and DHA represent only two kinds of omega-3 fatty acids. Scientists have identified over 30 other polyunsaturated omega-3s to date.

Today, fish oil is practically synonymous with the word ‘omega-3s.’ While it’s true that fish oils are potent sources of omega-3 fatty acids, natural fish oil contains far more than EPA and DHA. Natural cod liver oil, for example, contains a good amount of lesser-known omega-3 fatty acids, like DPA omega 3. While DPA hasn’t been researched as much as EPA and DHA, research shows that it has potent anti-inflammatory effects and cardiovascular benefits. Cod liver oil also delivers a range of other healthy fats besides omega-3s. In a teaspoon of cod liver oil, you’ll find saturated and monounsaturated fats similar to the ones in extra virgin olive oil and avocados.

Depending on how cod liver oil is made, it may contain vitamin A, D, and E – as well as co-factors like melatonin. (In most products, however, these vitamin levels are significantly reduced after the oils are purified of pollutants). Though natural fish oils contain many nutrients, the omega-3 industry is increasingly focused on isolating just EPA and DHA. For pharmaceutical companies, it’s lucrative to obtain new patents by concentrating specific omega-3s into prescription medications.

Concentrating omega-3s also has a dose advantage. In the United States, omega-3 supplements usually come as fish oil or cod liver oil pills. Therefore, the more concentrated the oil is, the fewer pills consumers theoretically have to swallow to get an effective omega-3 dose. Sadly, highly concentrated omega-3 products retain only a fraction of the nutrients found in natural fish oils. Some concentrates contain exclusively EPA; others contain only DHA. Of the products that provide both EPA and DHA, the fatty acid ratios can differ tremendously. How these products are concentrated – and their resulting chemical forms – also vary. Today, there are ethyl ester omega-3s, omega-3-carboxylic acids, and more. These chemically modified versions of EPA and DHA do not exist in nature. Highly concentrated fish oils and prescription omega-3s typically contain just a fraction of the nutrients found in natural fish oils.

As omega-3 research has progressed, the efficacy and safety of omega-3 supplements occasionally come into question. Some studies indicate significant benefits, while others find no improvements – or even adverse effects. Scientists have many theories to explain the conflicting results. But, one fundamental problem is that omega-3 studies use products with disparate nutrient profiles, chemical forms, dosages, and freshness levels. Given all these variations, it’s not surprising that “fish oil supplements” as a group fail to perform consistently.

Cell and mice studies have revealed that formulations made with differing ratios of EPA and DHA affect inflammation differently. Studies also show that an omega-3 oil’s chemical form influences how well it is absorbed. D and freshness impact results, too.

As omega-3 research evolves, it continues to uncover new nutrients in fish oils – like DPA, SPMs, omega-7, and wax esters. These findings invite familiar questions. Are EPA and DHA alone what make fish oil beneficial? Or do we suffer from the same tunnel-vision as the vitamin A and D-obsessed scientists at the start of the 20th century? There is no doubt that studying isolated fatty acids has its merits. Besides making research easier, it gives us better insight into how these nutrients work in the body.

In reality, the human body doesn’t just rely on one or two nutrients to function. Usually, several different molecules interact with each other to create beneficial effects. That is why counting on just one drug or synthetic fatty acid to fix a problem isn’t logical. Other industries seem to have understood this. With extra virgin olive oil, we know that excessive processing negatively impacts health benefits. Similarly, hemp manufacturers regularly discuss the ‘entourage effect’, which explains why the multitude of nutrients in full-spectrum hemp oil perform better than extracts."

The Weston A. Price Foundation considers cod liver oil the number one super food. They state, "Once a standard supplement in traditional European societies, cod liver oil provides fat-soluble vitamins A and D, which Dr. Price found present in the diet of “primitives” in amounts ten times higher than the typical American diet of his day. Cod liver oil supplements are a must for women and their male partners, to be taken for several months before conception, and for women during pregnancy. Growing children will also benefit greatly from a small daily dose.

Dr. Price always gave cod liver oil with high-vitamin butter oil, extracted by a slow centrifuge from good quality spring or fall butter. He found that cod liver oil on its own was relatively ineffective but combined with butter oil produced excellent results. We now know that butter oil is an excellent source of vitamin K, which is needed to balance vitamins A and D in cod liver oil. Other good sources of vitamin K in western diets are aged cheeses and the fat and livers of ducks and geese; other sources include butter and egg yolks. Without the balance of vitamin K, cod liver oil could lead to heart troubles, bone problems, tooth decay and gum disease.

Likewise, the omega-3 fatty acids in cod liver oil require balance by omega-6 arachidonic acid (AA), found in butter, meat fats, organ meats and egg yolks. Without the balance of AA from animal fats, cod liver oil could contribute to skin problems and digestive problems.

It’s all about balance! Be sure that when you take cod liver oil you also include sources of AA and vitamin K in your diet."

The Weston A. Price Foundation gives recommendations on cod liver oil dosing in an article titled, "Cod Liver Oil Basics and Recommendations." [14]

The best advice, based on the information presented by Dr. Martinsen and the Weston A. Price Foundation, is to take cod liver oil but rotate the brands and determine which one provides the most benefit. Also, include natural wild-caught cod livers into your diet recognizing that taking the liquid or pill form of cod liver oil is a more convenient method of delivery.

[1] Wendt, Diane. "The Man with a Fish on his Back: Science, Romance, and Repugnance in the Selling of Cod-Liver Oil." Chemical Heritage 28.1 (2010): 32-6. [2],precursor%20to%20vitamin%20D3.,be%20lacking%20in%20the%20diet. Accessed May 8, 2022. [3], Accessed May 8, 2022. [4] US3071457A - Process of applying sea solids as fertilizer [5] Beltz, B. S., Tlusty, M. F., Benton, J. L., & Sandeman, D. C. (2007). Omega-3 fatty acids upregulate adult neurogenesis. Neuroscience letters, 415(2), 154-158. [6] Gesch, C. Bernard, et al. "Influence of supplementary vitamins, minerals and essential fatty acids on the antisocial behaviour of young adult prisoners: Randomised, placebo-controlled trial." The British Journal of Psychiatry 181.1 (2002): 22-28. [7] Corrigan, Frank, et al. "Fatty acid analysis of blood from violent offenders." Journal of Forensic Psychiatry 5.1 (1994): 83-92. [8], October 17, 2006. [9], March 24, 2021. [10] Hospital for Consumption and Diseases of the Chest. The First Medical Report of the Hospital for Consumption and Diseases of the Chest, presented to the Committee of Management by the Physicians of the Institution. J Churchill, 1849, pp. 31-41. [11],precursor%20to%20vitamin%20D3, September 13, 2021. [12], September 5, 2002. [13], June 16, 2021. [14], February 9, 2009.


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