Introduction
In a previous article, I argued that a recent drop in the body temperatures of the Tsimane people of Bolivia was caused by the introduction of vegetable oil to a mostly starch diet. Native Americans used acorns as a staple starch, but they removed the oil form them before eating. However, they often added animals fats, most commonly bear fat, to their starches.
Acorn oil is not THAT high in polyunsaturated fat and acorns aren’t that oily, but if the acorn is a staple of your diet you could still manage to consume enough PUFA to affect your metabolic rate. This would have led you to be very cold in the North American climate. I suspect the Native Americans knew this.
First hand reports show clearly that Native Americans were removing acorn oil, both in California and on the East coast.
The acorn was a staple across the US. East coast Native Americans grew corn and beans and often made cakes that combined two or all three of these. Native Californians never took up agriculture. They lived in a paradise where a year round supply of acorns could have been gathered in just a few weeks in the fall.​1​ Acorns were the primary staple of the Native Californian.
Acorns are mostly starch, with a protein content below 10% and typically are around 8% oil, although some species have as much as 18% oil.​2​
Acorn oil is similar in composition to avocado or olive oil, but with a little more linoleic acid.​3,4​ It varies a little by species, but the predominant fat is always oleic acid, an 18 carbon monousaturated fat (MUFA). It has from 16-22% linoleic acid, an omega-6 polyunsaturated fat (PUFA), depending on the species. It has 2% or less of omega 3 alpha-linolenic acid.
Most acorns are high in tannins, making them bitter. The tannins are typically removed by either leaching them out by pouring water over them a numbers of times or by boiling them in several changes of water.
California
Lets look at California first. I find this passage to be particularly illuminating.​1​
California Native Americans knew which species of acorns were oilier and they used hot water to leach out the tannins of the oilier varieties, instead of cold water! This removed the oil. What is more extraordinary about this observation is that Native Americans didn’t have steel kettles before European contact, so water was boiled by heating stones in fires, then using wooden paddles to add the hot stones to water in woven baskets. That is a lot of extra work to go through if the end result is a loss of caloric value. Presumably the Native Californians wouldn’t have done this without a good reason.
Virginia
John Smith wrote this about the preparation of acorns in Virginia.​5​
It’s unclear exactly how long “half the day” is, but what IS clear is that the oil (oyle) was removed from the acorns by boiling and used as an ointment rather than being consumed.
Starch Plus Fat
It is often suggested in the keto diet community that combining starch with fat is a particularly fattening food combination. Perhaps Native Americans simply didn’t want to eat a combination of starch and fat? Seemingly not. Consider this description of Native American corn cakes.​6​ I’ve seen other descriptions of similar cakes combining corn and acorn meal.
Or “rye” cakes buttered with deer suet.​5​
Or “potatoes” with bear grease.​6​
The potatoes would have been tubers of the arrowhead plant, a very common wetland plant that grows throughout the entirety of the US. The arrowhead tubers are very high quality, starchy tubers, much like a potato.
“Sagittaria is an aquatic plant with tuberous roots that can be eaten like potatoes. Lewis and Clark found it at the mouth of the Willamette and considered it equal to the potato, and valuable for trade. Indian women collected it in shallow water
from a canoe, or waded into ponds or marshes in the late summer and loosened the roots with their toes. The roots would rise to the top of the water where they were gathered and tossed into floating baskets. Tubers are baked in fire embers, boiled, or roasted in the ashes. Tubers are skinned and eaten whole or mashed.”​7​
- 1.Mayer P. MIWOK BALANOPHAGY: IMPLICATIONS FOR THE CULTURAL DEVELOPMENT OF SOME CALIFORNIA ACORN-EATERS. Berkeley; 1976. https://digitalassets.lib.berkeley.edu/anthpubs/ucb/text/arfs015-001.pdf
- 2.Bainbridge D. Use of Acorns for Food in California: Past, Present, Future. PSFRES; 1987. https://works.bepress.com/david_a_bainbridge/43/
- 3.Lopes IMG, Bernardo-Gil MG. Characterisation of acorn oils extracted by hexane and by supercritical carbon dioxide. European Journal of Lipid Science and Technology. Published online January 2005:12-19. doi:10.1002/ejlt.200401039
- 4.Kaplan M, Kokten K, Bengu AS, Kardes YM, Das A, Sekerci AD. Fatty Acid Composition of Different Quercus Species. Chem Nat Compd. Published online March 2019:313-315. doi:10.1007/s10600-019-02675-x
- 5.Smith J. The Voyages and Discoveries of Captain John Smith in Virginia. Oxford; 1612.
- 6.Adair J. The History of the American Indians; Particulary Those Nations Adjoining to the Mississippi, East and West Florida, Georgia, North and South Carolina, and Virginia. London; 1755.
- 7.NRCS U. Broadleaf Arrowhead. USDA; 2003. https://plants.usda.gov/plantguide/pdf/cs_sala2.pdf
I don’t have knowledge or an opinion either way on this, but I read the passage about the blue vs black acorns a little differently, with the mention of a “tradeoff”, though I may be missing something…
Could the passage instead just indicate that the black acorns have more tannins than the blue acorns, so they were willing to sacrifice some of the [perhaps nutritionally valuable] oil because they wanted to get rid of the unappealing/bad tasting tannins?
Yes, so the explanation for the black vs. blue acorns is by a European observer. I don’t accept the European’s interpretation of the observation. I think the European is struggling to make logical sense of it. It doesn’t make sense anyway. Why go to all the trouble to boil the water when cold water seems to leach tannins just fine?
Awesome and interesting blog post! Thanks for posting those snippets of native American culture! I always find it fascinating when we see traditional cultures/diets that differ from our beliefs!
Hi Brad, are you aware of convincing date regarding Vit A and SCD1?
Does Vit A up- or down-regulate SCD1?
I haven’t looked into it that much. There’s a possibility that Amber O’Hearn will write a companion piece to The SCD1 Theory of Obesity on that exact subject.
Brad
Very interesting indeed.
If you’re looking for additional information, this blog, by Will Buckner research assistant in the Department of Anthropology Pennsylvania State University, might have some nuggets. Here’s a recent post that has some interesting details along the lines of your post:
https://traditionsofconflict.com/blog/2021/2/5/the-limits-of-the-proposed-behavioral-immune-system
You can’t really make this argument: “It is often suggested in the keto diet community that combining starch with fat is a particularly fattening food combination. Perhaps Native Americans simply didn’t want to eat a combination of starch and fat?”
For one, some of us (like me) actually CAN eat many croissants (made from butter only) with butter on them. I can easily eat 3 of these, with zero issues. And be hungry not too long later. (The real issue: why? Why can some of us do this and others not?)
For two, it’s difficult to compare the modern way of eating and having an abundance of food with a place where food is sketchy at best. Sure, if you have plenty as a Native American, you eat plenty. Because if you don’t, the long winter could kill you. You need the calories.
For three, it’s hard to compare Native Americans with those of us of European ancestry. They likely didn’t (couldn’t?) gain 90+ pounds more than they should weigh, as I did. What is “good” for someone with reasonable metabolic health may not be good for someone who gained a ton of weight and lost a lot but not all of it.
I have a colleague who eats Cheerios for lunch. Yes, Cheerios. He eats a small bowl and is thin. Were I to eat those, I’d eat 4+ bowls with zero issues and still be hungry 30 minutes later. Whether this is genetics or something else, I don’t know. But it’s hard to do these “here’s what these people with different genetics, time of living, culture, lives, etc. ate, and therefore you, with completely different everything should be eating.”
I know people are looking for the “one theory” that explains everything (Kitavans, French, etc.), but maybe that theory doesn’t exist? Maybe there are some of us who don’t follow those rules? Maybe you need multiple theories. That is, there really are those of us for which fat (even lots of saturated fat) and starch is bad?
Bob, respectfully, Brad accounts for the nuance you are looking for.
See his posts on epidemiology.
A lot of it depends on your existing fat stores, which are likely to be throwing off the body’s natural way of burning fat.
To be clear, people DO argue that fat plus starch is particularly fattening. I know that wasn’t your point but I wanted to clarify for others.
We also know that there WERE fat Native Americans pre-contact: those who ate only maple sugar.
So Native Americans COULD get fat but we don’t really know HOW fat.
Anyway, the point that I’m making here is “Why are Native Americans removing the oil from acorns? Do they think that combining starch and fat is bad?” The answer to this question is a definitive NO. The Native Americans somehow or other, clearly thought bear fat was superior to acorn fat and regularly mixed fat and starch. I find this interesting.
Of course if your metabolism is “broken” you will have very different experiences than Native Americans in 1700, but I’m trying to get at the roots of what does a healthy metabolism look like and why does it break in the first place.
Brad
With regards to sat fat + starch:
I’ve noticed folks saying that when they have plenty of stearic acid butteroil + starch they will wake up the next day in ketosis despite carb intake. I notice this myself (the lack of water weight fluctuation despite eating carbs is pretty sweet).
Is the physiological insulin resistance the key to why this might happen? I’m a little confused how glycogen storage fits in here, but not accounting for that are you proposing something along the lines of:
Sat. Fat + starch: ROS -> physiological insulin resistance -> blocked glucose ingress into cells -> excess glucose shuttled through de novo lipogenesis (which remains saturated because the physiological insulin resistance is due to ROS generation which will also result in downregulated SCD1) -> what little glucose cells did take in pre-physiological insulin resistance runs out overnight(???)
as opposed to
polyunsat. fat + starch: drastically reduced ROS -> no physiological insulin resistance -> unrestricted glucose ingress into cells -> larger amounts of glucose to burn through before cells are depleted of it
Am I on the right track with this, or am I missing something?
I’d say you’re on the right track! I’m not totally sure about the role of glycogen either!
I thought that bear fat was quite high in linoleic acid? What would be the point in removing the acorn oil and consuming bear fat instead?
Bear fat has a varying level based on the season – as little as 8% and as high as 25%. It seems that native Americans hunted them year round, so perhaps on average the bear fat was 15%? Either way, at the highest levels of linoleic acid, bear fat is only equivalent to that of acorn oil, but it also provides a good amount of palmitoleic acid (16 carbon monounsaturated Omega 7), a specific natural inhibitor of SCD1. If you read: https://fireinabottle.net/the-body-fat-saturation-of-starch-eaters-linoleic-acid-dysregulates-scd1/
You can see that up to perhaps 6-8% of overall calories as linoleic acid, the system self regulates quite well (if you had a healthy metabolism to begin with) and if you include more palmitoleic acid, perhaps you can go higher on linoleic acid before the system becomes dysregulated.
A little bear fat shouldn’t have a big effect on overall saturation of human body tissue. IFF you have a healthy metabolism to begin with….