The Real Paleo Diet
Since the 1970’s there’s been this fad
diet that keeps going in and out of fashion.
and one can generally assume
that fad diets are…. well fads
in five years
people lose interest again
and it will have turned out that we should have
been eating more vegetables and fewer chips and less sugar water
but we won’t do that because those things are delicious.
The Paleo diet is based on the idea
that humans evolved eating a specific diet
and because we aren’t eating the food we evolved to eat
we aren’t healthy.
Leaving aside the fact that humans are
now vastly more healthy than we were 50,000 years ago
because of advances in complicated techonologies
like toothpaste and soap
there is a certain amount of logic to this,
so it’s worth looking at.
What diet did humans evolve eating?
And would we be healthier if we matched it?
The trouble with the whole idea of matching what Paleolithic humans ate
is that if they were anything like today’s hunter- gatherer cultures,
and we think they were,
they ate very different things.
A 2000 study in the American Journal of Clinical Nutrition
reviewed the diets of over 200 different hunter gatherer cultures
and showed a huge range.
Carbohydrates were between 22 and 40 percent
with roughly the same spread for fat,
and protein was 19 to 56 percent of their diets.
The studies also found that these cultures
had a wide variety of calorie sources:
The Masai subsist mostly on meat, milk and blood
while cultures in New Guinea derive
almost all of their nutrition from plants.
There are certainly massive differences between what we eat
and what hunter gatherers eat,
and we would be well suited to include more dietary fiber, less salt
and way less sugar and refined carbohydrates
but none of that is new information.
There was no one diet that fit all Paleolithic peoples,
because their goal was to survive
and they did that however they could,
which they did marvelously and ingeniously.
All we can really say for sure about Paleolithic people
is that they did whatever they had to to stay alive.
But even if we did pick one of those cultures
and tried to eat what they ate,
we wouldn’t be able to,
because what they ate
aside from deer and bison
isn’t really available to us.
Almost all of the fruits and vegetables at the grocery store
have been selectively bred for thousands of years
to create the most nutritious and useful produce.
And the claim that our bodies haven’t kept up
with the changes in our diets doesn’t really hold up either.
The idea that humans can’t have evolved very much since the Paleolithic era
isn’t really true.
Studies suggest that we’ve developed
a few new adaptations just within the last few thousand years.
One of the more famous examples is that
all adults used to be lactose intolerant
but thanks to a relatively recent mutation
about 30% of the world can now eat ice cream.
And according to research published in 2007
in the journal Nature Genetics
the ability to better digest starch also evolved over time
The researchers tested 7 different populations
3 with high starch diets and 4 with low starch diets.
They found that people from the high starch populations
were almost twice as likely to have extra copies of a gene called AMY1
that codes for the starch digesting protein in saliva.
It didn’t matter whether they were European Americans
or Hadza hunter gatherers, they still had more copies.
It’s unlikely that the extra copies of AMY1
came from one mutation that spread
because they were found in groups that wouldn’t have had much contact.
Instead the researchers suggest that people
with extra copies of the gene were naturally selected for in all the groups
because they were able to get more nutrition
out of their starch rich diets.
Our bodies are versatile and they’re equipped to handle
a slice of bread or two.
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