Posted on 12/09/2004 10:44:58 AM PST by Helms
- 03-22-2004, 07:40 PM
By Gilien Silsby and Gia Scafidi
When our human ancestors started eating meat, evolution served up a healthy bonus - the development of genes that offset high cholesterol and chronic diseases associated with a meat-rich diet, according to a new USC study. Those ancestors also started living longer than ever before - an unexpected evolutionary twist.
The research by USC professors Caleb Finch and Craig Stanford appeared in the Quarterly Review of Biology.
"At some point - probably about 2 1/2 million years ago - meat eating became important to humans," said Stanford, chair of the anthropology department in the USC College of Letters, Arts and Sciences, "and when that happened, everything changed."
"Meat contains cholesterol and fat, not to mention potential parasites and diseases like Mad Cow," he said. "We believe humans evolved to resist these kinds of things. Mad Cow disease - which probably goes back millions of years - would have wiped out the species if we hadn't developed meat-tolerant genes."
Finch, the paper's lead author, and Stanford found unexpected treasure troves in research ranging from chronic disease in great apes to the evolution of the human diet. They also focused on several genes, including apolipoprotein E (apoE), which decreases the risk of Alzheimer's and vascular disease in aging human adults.
Chimpanzees - which eat more meat than any other great ape, but are still largely vegetarian - served as an ideal comparison because they carry a different variation of the apoE gene, yet lack human ancestors' resistance to diseases associated with a meat-rich diet.
While chimpanzees have a shorter life span compared to humans, they demonstrate accelerated physical and cerebral development, remain fertile into old age and experience few brain-aging changes relative to the devastation of Alzheimer's seen in humans today. Finch and Stanford argued that the new human apoE variants protected the chimpanzees.
In a series of "evolutionary tradeoffs," the researchers said, humans lost some advantages over those primates, but gained a higher tolerance to meat, slower aging and longer lifespan.
Still, if humans developed genes to compensate for a meat-rich diet, why do so many now suffer from high cholesterol and vascular disease?
The answer is a lack of exercise and moderation, according to the researchers.
"This shift to a diet rich in meat and fat occurred at a time when the population was dominated by hunters and gatherers," said Finch, a USC University Professor and holder of the ARCO-William F. Kieschnick Chair in the Neurobiology of Aging.
"The level of physical activity among these human ancestors was much higher than most of us have ever known," he said. "Whether humans today, with our sedentary lifestyle, remain highly tolerant to meat eating remains an open question researchers are looking into."
Stanford, co-director of the university's Goodall Research Center, said that modern-day humans "tend to gorge ourselves with meat and fat."
"For example, our ancestors only ate bird eggs in the spring when they were available," he said. "Now we eat them year-round. They may have hunted one deer a season and eaten it over several months. We can go to the supermarket and buy as much meat as we want."
"I think we can learn a lesson from this," Stanford said. "Eating meat is fine, but in moderation and with a lot of exercise."
Just wondering out loud here though...
How would we have "evolved into meat eating"?
Did someone wake up one day and all of a sudden have the ability to eat meat when all his collegues died from it?
An honest question, please don't flame me as putting down evolution or something like that.
I mean it though; if eating meat would have killed us before we "evolved into eating meat" how did our ancestors know to eat meat in the first place?
If they repeated what other animals did, then they ate meat and died of parasites long before they got the gene.
If they didn't, how did they know to start eating meat?
Hence the k-9's! :)
I just had a big hamburger, fries and a glass of milk for lunch. I also take medicine for high cholestoral.
Dry Aging meat is done at many restauraunts and was the most popular form of aging used until a few decades ago, Today we use mostly the wet aging method.
A dry aged steak actually doesnt allow any mold to form it allows the prime or side cut to form a rind, much like aging a cheese. It also takes longer to dry age beef, compared to about a 3 day wet age used to today. If you dont age beef it will be extremely tough and mostly good for only hamburger.
A dry aged steak is also much more tender than a wet aged one, the cellular structure of the meat actually breaks down a little and provides far better flavor. If you ever hear an older person say beef doesnt taste like it used its because the mass marketing of beef has denigrated its quality.
117/68 sys/dys.
I eat like you do regularly. red meat, chicken, fish, eggs, milk. I have some each meal of at least one of these. My dad has high blood pressure though... I guess I'm just lucky... that and martial arts and a type C personality does wonders :)
They probably just built up an immunity after a few years and after a few thousand years it became genetically encoded. I dont think they ate meat and died the next day, but more than likely got the squirts or a fever.
Potato Famine.
"If you ever hear an older person say beef doesnt taste like it used its because the mass marketing of beef has denigrated its quality"
That and a loss of the sense of taste and a nostalgic outlook on life "my childhood bedroom used to be much larger"
I actually watch what I eat. Today was an excursion from my mostly vegetable and fish diet. My dad and two of my brothers died of heart attacks at age 51. I just turned 61 and am in good health except for slightly elevated cholestoral.
Is that a picture of a PETA person caterwallering about eating meat?
So its more likely they simply didnt have the MEANS to get meat on a regular basis until AFTER they developed the genetics to properly consume it...
Fascinating actually. This is akin to (IMO) the development of harvest grain at right about the time farming began. (some 8,000 years ago if i recall my notes correctly.)
Until that point, farming grains would have been rather useless, as the crude methods and wild oats would have made (more or less) a lot of big dirt pits in early Mesopotamia.
If this info seems off to anyone, feel free to comment. It's based on the teachings of a prof of mine that has more or less expressed that communism didn't work simply because fo the people in charge... not exactly stellar researcher in my opinion, but an overall good guy.
Please, take it with a grain of salt.
BTW, if both of these ideas are fully correct, it only shows me someone awful big was looking out for us then. Most likely still is :)
cured meats happened for a reason.
PETA vs. Darwinists. Godlessness makes strange bedfellows.
Our organs and metabolisms evolved to handle meat. We were probably always omniverous, but couldn't get as much of the big-ticket items because we couldn't chase the predators away.
Consider how certain ruminants have three-chambered stomachs, the better to break down fibrous materials like grasses.
Of course, feeding ruminants to ruminants is considered the main reason why Mad Cow developed.
I am a psuedo-Vegan.
I only eat meat that died from natural causes......
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