
Animals living alongside humans produce amylase, enzyme that breaks down starch - 100c1p43r
https://elifesciences.org/articles/47523
======
gumby
Although I follow a ketogenic diet and benefit from it I have laughed about
the claims that it's somehow aligned with the needs of Paleolithic people. SO
I really enjoyed this: "Unlike Neanderthals and Denisovans, who had only two
diploid copies, we carry up to 20 copies of the AMY1 gene, which produces
salivary amylase. "

~~~
Noumenon72
Isn't that the opposite of what you believe? Paleolithic people were not
genetically adapted to high-starch diets like we are. Ergo, a low-carb diet
like keto was more natural for them.

~~~
codemac
The "we" in the sentence is homo sapiens. Neanderthals and Denisovans were not
the same species as us.

> "Unlike Neanderthals and Denisovans, who had only two diploid copies, [homo
> sapiens] carry up to 20 copies of the AMY1 gene, which produces salivary
> amylase. "

~~~
arcticbull
Doesn't that mean we've evolved to eat a lot of starch so the more natural
thing for humans to eat is therefore starch, if you follow this line of
reasoning? And therefore, we've "evolved beyond" the keto diet?

FWIW, I do not think this is good reasoning.

~~~
akiselev
OP is not making a claim here, he is pointing out counter evidence to someone
else's claim, which is that keto diets are optimal for homo sapiens because
that is what our genetic ancestors evolved to eat. The presence of
significantly more genes for amylase provides strong (although far from
conclusive) evidence that homo sapiens have evolved to eat a much more varied
diet than paleo proponents assert.

~~~
chrisco255
Paleo diet mainly prohibits wheat and refined carbs but allows for specific
starches such as sweet potatoes. It's different than keto. At any rate, the
existence of enzymes does not indicate that starches should make up a large
portion of one's diet either, as we must admit the past century of relative
plenty in the Western world has led to all sorts of dietary diseases.

------
spraak
> This may suggest that our lineage has evolved specific adaptations to digest
> starch-rich foods, underlining the long and continuing importance of these
> staples in our diet

This reminds me of the interest in keto dieting and the frustrating
misunderstanding that carbs are the cause of excess weight, diabetes etc. If
that were true, the whole world would be diabetic and obese, since everywhere
has a staple carb. It's only with excess calories and fat that carbs
contribute to, but are not the cause of, the problem.

~~~
BurningFrog
Until recently, everyone has lived near the border of starvation, and not had
an opportunity to get obese.

Since the agricultural revolution, carbs are what we have been able to mass
produce, and therefore breed ourselves to greater numbers on. That it probably
hasn't been the ideal diet for us is a distant secondary concern.

Now that we're _finally_ overproducing food, we actually are getting obese on
the carb diet. Coincidence? Maybe.

~~~
twic
I think the Venus of Willendorf and her equally thicc cousins are, if you'll
excuse the expression, ample proof that some people had an opportunity to get
obese long before the agricultural revolution.

~~~
blaser-waffle
Didn't someone put a theory out that the Venus of Willendorf was not
venerating the Fat Goddess, but rather what someone sees when they look
straight down at their body?

(cuz cave people didn't have good mirrors and all)

Deeper explanation: [https://steemit.com/science/@deeallen/self-portraits-of-
fert...](https://steemit.com/science/@deeallen/self-portraits-of-fertility-
symbols-venus-figurines-of-upper-paleolithic-eurasia-nudity)

~~~
twic
There are all sorts of theories!

Olga Soffer points out that the woven clothing on the figurines is often
incredibly detailed, and suggests they may have been some kind of fashion doll
[1]. Mandy Weston speculates that they may be bobbins used for weaving [2]!

[1]
[https://www.researchgate.net/publication/235979951_The_Venus...](https://www.researchgate.net/publication/235979951_The_Venus_Figurines_Textiles_Basketry_Gender_and_Status_in_the_Upper_Paleolithic)

[2] [https://www.academia.edu/31112020/Venus_Figurines_-
_Evidence...](https://www.academia.edu/31112020/Venus_Figurines_-
_Evidence_of_Womens_Work)

------
mrob
The argument for keto/carnivorous diet does not depend on human adaptation to
digesting starches. I understood it as:

* Evolution works at the level of genes, not individuals. It will select for short-term reproductive success at the expense of longevity or quality of life.

* All living things evolve to avoid being eaten (at least while they have the potential to reproduce or aid the reproduction of their kin).

* Animals primarily defend against being eaten by fleeing or fighting. These defenses can be 100% neutralized by killing the animal.

* Plants primarily defend against being eaten by producing toxins. These defenses can be neutralized by metabolism, but evolution has no incentive to select for 100% neutralization. If 100% neutralization of plant toxins is difficult then dying young with a lot of children might be a better strategy.

However, there are plants that defend with spines/shells/hiding underground,
and plants that produce fruit to attract animals for seed distribution, all of
which change the selection pressure for toxin production, and any food may be
healthful or harmful purely as a spandrel (a byproduct of evolution of some
other characteristic). There are examples of human populations maintaining
good health on a wide variety of different diets, so as is usually the case
with nutrition, there are no clear answers.

~~~
cageface
These arguments are all interesting but I think most relevant is that the best
nutrition science we have to date shows that a proper plant based diet is
optimal for health & longevity. The plants and animals we eat now are
radically different than the ones we were exposed to through most of our
evolution so paleo proponents are chasing a lost world.

~~~
ianai
Actually, the representation of the ancestral diet being primarily meat is
incorrect - outside of a few examples where there just weren’t many plants
available. Largely, humans ate what they happened upon. Meat was a scarce
byproduct of another predators meal. Ie we ate what the big cats left behind.

Furthermore, the ultra refined and concentrated foods we now eat didn’t exist
until very recently. The amount of sugar cane needed to produce a single can
of soda isn’t something any human would sit down to eat.

Edit-changed are to ate

~~~
chrisco255
Humans evolved during the ice age. There were no vegetables in large enough
quantities to feed the human brain's massive growth over the past million
years. Every single paleolithic cave art depicts animals and hunting
techniques. Fossil evidence from millions of years ago show bone scrapes on
zebra and reindeer bones in human caves. We evolved to hunt wooly mammoths
twice the size of elephants for goodness sake. We decimated whole populations
of megafauna. You would have to go back 4-6 million years ago to find
scavenger ancestors.

~~~
cageface
Cooking is very likely the reason humans suddenly had access to far more
calories to support a larger brain. The idea that an organ like the brain that
feeds directly on glucose was supported by animal fat and protein just doesn’t
hold up to serious scrutiny.

~~~
chrisco255
The brain is incidentally 60% fat. And all the glucose the brain requires can
be synthesized from lactic acid. There are entire societies that live off of
99% meat. They live their entire lives with almost no vegetable intake
whatsoever, and their brains develop and function perfectly normal. In
contrast, consuming too much glucose can wreak all sorts of havoc on the
brain, spurring excessive consumption, type 2 diabetes, and has been linked
with Alzheimer's.

[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3577529/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3577529/)

[https://www.nih.gov/news-events/news-releases/higher-
brain-g...](https://www.nih.gov/news-events/news-releases/higher-brain-
glucose-levels-may-mean-more-severe-alzheimers)

~~~
ianai
[https://www.alzheimersanddementia.com/article/S1552-5260(17)...](https://www.alzheimersanddementia.com/article/S1552-5260\(17\)33765-2/pdf)

“Studies have shown that type 2 diabetes can be a risk factor for Alzheimer’s
disease, vascular dementia and other types of dementia because cardiovascular
problems associated with diabetes are also associated with dementia. These
include:

Obesity Heart disease or family history of heart disease Impaired blood
vessels Circulation problems High cholesterol High blood pressure Research has
also proved that, similar to diabetes, glucose is not used properly in the
brains of people with Alzheimer’s disease. ”

[https://alzheimer.ca/en/Home/About-dementia/Alzheimer-s-
dise...](https://alzheimer.ca/en/Home/About-dementia/Alzheimer-s-disease/Risk-
factors/Diabetes-dementia-connection)

~~~
chrisco255
I'm not sure of your point, because the parent comment mentioned animal fats
and protein not being a primary food source for paleolithic humans and their
ancestors (which is not what the fossil evidence shows AT ALL, we created
spears and bows and arrows and various hunting strategies and tools that are
well documented, for millions of years).

But with regards to your type 2 diabetes comment, type 2 diabetes is strongly
associated with diet intake of excessive carbohydrates.
[https://www.ncbi.nlm.nih.gov/pubmed/30289048](https://www.ncbi.nlm.nih.gov/pubmed/30289048)
[https://www.ncbi.nlm.nih.gov/books/NBK499830/](https://www.ncbi.nlm.nih.gov/books/NBK499830/)

You don't need carbs in your dietary intake. Your body can synthesize carbs
from fat, just as it can synthesize fat from carbs.

------
Nasrudith
Hmm I wonder if it is just an adaptation (humans mean their staples are about
and it gets selected for) - or if it is something mutagenic. The fact it is
the same enzyme makes me wonder.

~~~
maxerickson
The wild animals have the genes, the ones associated with humans have multiple
copies of it.

~~~
Nasrudith
Ah I missed that aspect in my skim. The consistency excess copies seems to
imply that losing them entirely would be extra bad for survival enough so that
redundant copies would boost offspring survival and dominate for human
adjacents but not their more wild counterparts.

The domestification might even imply reverse order - that the ones with the
starch genes were more likely to wind up in "dog" pools - say because they
were attracted to starch and got closer to humans - and thus plenty of extra
copies among their descendants. Meanwhile ones without were more likely to
stay away and their descendants more likely to wind up in "wolf" pools where
prevalence was lower.

------
jp57
The image of the wolf with the deer leg in its mouth and the German shepard
with the pizza slice in its mouth is basically the entire tl;dr.

~~~
trhway
Good quality dog food is closer to deer leg then to pizza. Unfortunately there
are too much low quality made of unbelievable junk pet food around compare to
which even pizza sounds good and healthy. That prompts a lot health problems
to the dogs.

~~~
jp57
But specially made dog food has only existed for 100 years or so. Dogs evolved
eating humans' food scraps.

~~~
trhway
Yes, they are opportunistic carb eaters as a result of that evolution. The
business of the low quality dog food abuses that.

