I wanted to deal with all of these together because they are so intertwined and mutually supported by myths about wild game and hunter gatherer habits.
Since most people have the belief that we have to avoid “arterycloggingsaturatedfat” to avoid heart disease and a myriad other evils, and some authorities assure us that wild game carries very little fat, many people try to base their “Paleolithic” diets on skinless poultry and fish, and use olive and canola oils to get a high monounsaturated fat intake.
I made this mistake myself in my early attempts at paleodiet.
Some authors have asserted that ancestral Paleolithic diets were based on lean meats, low in saturated fats, and high in monounsaturated fats. They support these claims by citing the facts that muscle meat of the typical wild game species contains much less fat than meat from a grain-fed steer. It is true, the muscle meat of wild game has much less total fat than the muscle meat of grain fed animals.
However, as noted by Stephan in The Myth of the High Protein Diet, the ethnographic evidence clearly indicates that hunters did not hunt “typical” animals, nor eat only the lean muscle meat. Hunters universally preferred, pursued, and whenever possible brought home the bison (or other animal) that carried a large amount of fat.
Some authors have asserted that hunter-gatherers ate diets rich in monounsaturated fats, but low in saturated fats, primarily getting their fats from bone marrow. They frequently cite Cordain et al, who found that monounsaturated fat forms 60 to 67 percent and saturated fat only about 20 to 27 percent of marrow fat of North American deer, elk, and antelope (European Journal of Clinical Nutrition (2002) 56, 181–191). These authors recommend avoiding animal fats while using large amounts of olive or canola oil to achieve a high intake of monounsaturated fats, supposedly to mimic Paleolithic diets.
Although the data collected by Cordain et al affirms the high monounsaturated fat content of marrow, it does not prove that hunters had a diet high in monounsaturates and low in saturated fats. One must ask, does the marrow provide the bulk of the fat on an animal? Of course not! On any healthy animal, subcutaneous fat will far outweigh the marrow fat.
How much fat could inland people get from hunting large, wild grazing animals? Let me quote from my book:
“ Even if a 1500-pound bison had only 3 percent of its body weight as stored fat (a very lean animal), the yield would be 45 pounds of highly saturated fat, providing 157,500 calories. By inciting the animals to stampede off a cliff or into a trap, the American Plains tribes typically killed from a few dozen to 200 bison at a time––yielding from 1600 to 9000 pounds of depot fat.”
The subcutaneous fat of wild game has a very high proportion of saturated fats. Cordain et al reported that saturated fat forms 60 to 65 percent of the subcutaneous fat of of North American deer, elk, and antelope (and monounsaturated fats form only about 25 percent of those animals’ subcutaneous fat). (European Journal of Clinical Nutrition (2002) 56, 181–191). For comparison, only about 45 percent of grain-fed beef fat consists of saturated fats.
If you live by hunting simple efficiency of effort dictates that you will seek the largest possible prey. Kill one bison and you have at least 500 pounds of meat; you would have to kill at least 100 birds to get the same food supply. The cave paintings and rubbish heaps left by our ancestors indicate they preferred hunting large animals including aurochs, mammoths, horses, deer, whales, and the like, not small game like chickens. Recent hunter-gatherers also focused their efforts on large mammals, not birds and lizards.
For example, Australian Aborigines and other South Sea tribes hunted dugong (a sea mammal). All edible parts of animals were consumed, including organ meats and fats. Also known as sea cows, dugongs weigh between 500 and 1800 pounds, and inhabit shallow tropical waters. People hunt them with harpoons and gill nets. An average adult dugong provides 24 to 56 liters (6 to 15 gallons) of oil.
Native American Plains bison hunters ate some of their bison meat fresh, but much was dried.
They ground the dried meat to a powder and mixed it with berries and an equal weight of bison fat to make pemmican, a cake that remains solid in storage. Plains tribes made and stored enough pemmican for their own needs and had a surplus that was a favored trade item. During the historic fur trade, the Plains tribe traded tons of pemmican.
You can’t make pemmican without using a highly saturated fat; unsaturated fats will not form a cake because they remain too soft even at 32 degrees F.
Those who fear animal fats simply do not understand that their own human fat as as much saturated fat as beef or pork fat. Take a look at this chart from my book:
| Fat Source | Saturated Fats(%) | Monounsaturated Fats(%) | Polyunsaturated Fats(%) |
| Animal | |||
| Human | 42.9 | 46.9 | 10.2 |
| Beef Tallow | 47.8 | 49.6 | 2.6 |
| Lard | 40.0 | 50.0 | 10.0 |
| Butter | 62.6 | 28.6 | 3.4 |
| Chicken fat | 29.6 | 44.5 | 21.0 |
| Vegetable | |||
| Corn | 8.0 | 24.2 | 58.8 |
| Flax | 9.6 | 17.0 | 68.8 |
| Olive | 14.3 | 77.1 | 9.3 |
| Palm | 49.3 | 36.8 | 9.6 |
| Sesame | 14.0 | 39.7 | 41.2 |
As you can see, lard, beef tallow, and palm oil all have a fatty acid profile very similar to human body fat. You will note also that the profile of butter is very similar to that of wild game subcutaneous fat as reported by Cordain et al (above).
In fact, the fatty acid profile of the fats of various mammals remains remarkably similar from species to species. This indicates that evolution has favored and conserved the production and use of saturated fats in mammals.
Why? Well, for one thing, mammals have a body temperature of approximately 100 degrees F, and a continuous supply of oxygen. Heat and oxygen easily damage unsaturated fats, not so for saturated fats. Further, at 100 degrees F, monounsaturates and polyunsaturates are too fluid for many of the ways mammals use fats.
As a general rule, when you look at nature, organisms that inhabit cold climates or have low body temperatures (e.g. flax, salmon) have a predominance of unsaturated fats in their tissues, and organisms that inhabit warm climates or have tropical body temperatures (coconut, palm, humans, cows) have a high proportion of saturated fats in their tissues. This is simple adaptation to environment--a salmon could not inhabit cold waters with a high body content of saturates, because it would freeze solid.
That means, between meals or during fasts, your own adipose tissue releases into your blood stream a collection of fatty acids very similar to any other mammalian fat. Evolution has designed us to produce, store, and use saturated fats for both structural and metabolic purposes. You need have no fear of saturated fats. You can eat fatty meats and animal fats; you don't have to strive for a high monounsaturated fat intake; and you can enjoy the lip-smacking deliciousness of it all.
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