Portrait of David Wetzel

David and Barbara Wetzel founded Green Pasture Products in 2000.  They produce nutrient dense Fermented Cod Liver Oil and High Vitamin Butter Oil, as well as offering other products. Today is David’s birthday.  I captured the photo of him above in Nebraska in January 2011.  I feel incredibly blessed to consider David to be a trusted friend and to collaborate with him as a colleague, and visual communication client.

David and Barbara are amongst the most generous people I have ever encountered, and their spirits and products nourish me deeply.  They have been consistent supporters of Nourishing Our Children and their extraordinary benevolence has been invaluable.

As I mentioned, in 2011 I traveled to Nebraska to visit David, Barbara and their 6 children.  Here is an album of some of the photos I captured while there. I went for both business and pleasure.  David and I created a PowerPoint which includes a history of cod liver oil that he has presented to a number of Weston A. Price Foundation chapters.  He also presented it at the last Wise Traditions conference in November of 2011.  In honor of David’s birthday, I thought I’d share some of the narrative of his presentation here, and will continue to do so in subsequent posts to come in the days ahead.

A History of Cod Liver Oil  

We’ll start with a relatively brief history of cod liver oil, and the making of fish oil products from the beginning of written history.

There is a long, rich history of fish oil and cod liver oil in particular.  Fish oils and organs are written about in the ancient bible’s “Book of Tobias” which is still part of the Catholic Bible.  “Raphael teaches Tobias how to use the organs and oil of fish to heal blindness and ward off evil spirits.”

Photo of Roman Soldier Statue


In Roman times, fish guts (visera) were placed in a barrel with sea water and allowed to ferment. What came out of the bottom of the barrel was a watery fermented fish sauce called garam, widely used as a seasoning (probably the precursor of Worcestershire sauce).  It was an essential flavor in Ancient Roman cooking, the supreme condiment.

For the Romans it was both a staple to the common diet and a luxury for the wealthy. After the liquid garum was ladled off of the top of the mixture, the remains of the fish, called allec, was used by the poorest classes to flavor their staple porridge. Among the rich, the best garum fetched prices parallel to the precious essences used in perfumery. Garum appears in most of the recipes featured in Apicius, a Roman cookbook, which also offers a technique to render palatable garum that had gone bad. The sauce was generally made through the crushing and fermentation in brine of the innards of various fishes such as mackerel, tuna, eel, and others. While the finished product was apparently mild and subtle in flavor, the actual production of garum created such unpleasant smells as to become relegated to the outskirts of cities so that the neighbors would not be offended by the odor.

Garum is full of water soluble nutrients: carnotine, biotin, niacin, and others … what would rise to the top was the oil and the Roman soldiers credited their strength to this oil and wouldn’t march without it.

Tapestry with Viking HatVikings

Later in history, during Viking times, we see mention specifically of cod liver oil – they would get the livers of the cod, which were plentiful during that time period and put those in drums in front of their houses.  Vikings used cod liver oil as a lubricant to allow the transport of ships across land—the oil was smeared across logs, which acted as rollers beneath the hull of the ship. Cod liver oil also formed part of the Viking diet.

David notes that the Vikings would get livers from the cod and every house would have a drum full of fermented livers and the oil that rose to the top was used for everything from heat, to cooking oil, to a condiment, to using the oil as fuel for a wick.  They would take spoonful upon leaving their homes.

Cod Fish Illustration


The cod family (Gadus sp.) is one of the largest and most successful families of fish, found in all oceans of the world. There are more than 90 species of cod, of which 40 are commercially available as oils.

Even in the same waters, different species of the Gadus family can have great a variation in fatty acid profile and vitamin A and D content. In Norway, the species that produce the greatest concentrations of A and D are Gadus virens and Gadus pollachius. Their oils contain as much as to 5000 IU vitamin A and 500 IU vitamin D per gram. (That’s 25,000 IU vitamin A and 2500 IU vitamin D per teaspoon!).These two varieties are common in waters off the Shetland Islands. At the other extreme is Gadus gadiculus thori, which produces 500 IU vitamin A and 50 IU vitamin D per gram of oil–just one-tenth as much. This species is found close to the shores of Norway.

Cod also grows in fresh waters. The Great Lakes are host to a species of fresh water cod called burbot or “lawyers,” which tests carried out during the 1940s indicated to be a very rich source of vitamin D. Unfortunately, the Great Lakes fresh water cod has received little interest since then, and most recreational fishermen consider the burbot a nuisance fish.

The great difference in levels of fat-soluble vitamins is due principally to differences in enzymatic liver activity in the various cod species. Within the same species, feed, age and location will account for additional variations in the nutrient profiles of the oil.

Cod liver oil provides not only vitamins A and D, but also valuable fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). As with vitamins A and D, levels of EPA and DHA vary according to the species and the temperature of the waters in which they dwell. For example, Gadus morua from the Atlantic typically provides oil containing 8 percent EPA and 12 percent DHA while the same species in the Baltic Sea provides 9 percent EPA and 20 percent DHA. Another species, Gadus merluccius, typically has 17 percent EPA and 10 percent DHA.

Fermented Cod Liver Oil

A description of traditional cod liver oil processing is provided by F. Peckel Möller in an article entitled Cod-Liver Oil and Chemistry published in London, 1895. “The primitive method is as follows. As soon as the fishermen reach the Voer [pier], and finish separating the livers and roes, they sell the fish and carry the livers and roes up to their dwellings.”

“In front of these are ranged a number of empty barrels into which the livers and roes are placed, separately of course. The fishermen do not trouble to separate the gall-bladder from the liver, but simply stow away the proceeds of each day’s fishing, and repeat the process every time they return from the sea, until a barrel is full, when it is headed up and a fresh one commenced. This is continued up to the end of the season, when the men return home, taking with them the barrels that they have filled. The first of these, it may be noted, date from January, and the last from the beginning of April, and as on their arrival at their homes the fishermen have many things to arrange and settle, they seldom find time to open their liver barrels before the month of May. By this time the livers are, of course, in an advanced state of putrefaction. The process of disintegration results in the bursting of the walls of the hepatic cells and the escape of a certain proportion of the oil. This rises to the top, and is drawn off.”

“Provided that not more than two or three weeks have elapsed from the closing of the barrel  to its being opened, and if during that time the weather has not been too mild, the oil is of a light yellow color, and is termed raw medicinal oil. As may be supposed, however, very little oil of this quality is obtained. Indeed, as a rule there is so little of it that the fishermen do not take the trouble to collect it separately. Nearly all the barrels yield an oil of a more or less deep yellow to brownish color: this is drawn off, and the livers are left to undergo further putrefacton. When a sufficient quantity of oil has again risen to the surface, the skimming is repeated, and this process is continued until the oil becomes a certain shade of brown. The product collected up to this point is known as pale oil.”

“By this time the month of June has generally been reached, and with the warmer weather the putrefaction is considerably accelerated, and the oil now drawn off is of a dark brown colour, and is collected by itself. It is rather misleadingly called light brown oil . When no more can be squeezed out, the remainder is thrown into an iron caldron and heated over an open fire. By this process, the last rests of oil are extracted from the hepatic tissues, which float about in the oil like hard resinous masses.  In order to fully carry out the extraction, it is necessary to raise the temperature considerably above the boiling point of water. The oil prepared in this way is very dark, almost black, and with a greenish fluorescence in reflected light. In thin layers and by transmitted light it shows a brown colour, and it is therefore termed brown oil.”

The writer then describes processing methods introduced to Norway in the 1850s by Peter Möller, which resulted in a much purer, consistently light-colored oil made from fresh, not putrefied livers, considerably more palatable in terms of taste and smell. He notes, however, that the “brown oils are actually used to a certain extent for medicinal purposes at the present day.” Perhaps the dark brown oils contained, in addition to vitamins A and D, vitamin B12 and other nutrients from the hepatic tissues.


Photo of 20 Dollars on a Fish HookIn his presentation, David explains: “Throughout history, from Roman times to Viking times, it took 5 to 6 months to ferment the cod livers.  As early as 1850 some of the industrialization started to take hold.  They found that if one heats those livers – which is a process referred to as rendering, they could pull the oil from the livers in a day rather than 5 or 6 months.  They didn’t understand what it would do to these oils.  But, they did understand profits and that industry was born.”

I  cover the industrialization of cod liver oil in the next post!


Meanwhile, thank you, David and Barabra Wetzel for restoring the ancient art of fermented cod liver oil production and for providing us with this sacred food.  I celebrate you, David Wetzel.  I would like to give you a standing and prolonged ovation for the life you lead, for the inspiration you offer, the integrity and values you uphold, the grace and generosity of spirit you possess, and the love that you offer freely to those who are blessed to cross your path.