In his essay Concerning Spiritualism and Materialism, Ludwig Feuerbach wrote: "man is what he eats".
A diet that has been growing in popularity in recent years is called the paleo diet, or the caveman-, stone age-, or warrior diet. Its premise is that we ought to return to the eating styles of our ancestors from way back -- because it's more in keeping with our genetic makeup. The underlying theory is that civilization has corrupted our food supply through unsound food production and manipulation, which has lead to the onslaught of diet-related illnesses like obesity, diabetes and heart disease we are facing today. The only way out of this misery, proponents say, is to mimic the eating behaviour that once ensured the survival of our species for many thousands of years. The premise behind the plan is simple: 2.5 million years ago to 10,000 years, man didn't eat refined sugars, grains, or dairy, so we shouldn't either. Before agriculture and industry, humans presumably lived as hunter–gatherers: picking berry after berry off of bushes; digging up tumescent tubers; chasing mammals to the point of exhaustion; scavenging meat, fat and organs from animals that larger predators had killed; and eventually learning to fish with lines and hooks and hunt with spears, nets, bows and arrows. The naturally selected humans who eventually evolved into modern man -- ate these foods, the diet was naturally selected as well. But the details are a little more complicated than the simple theory that "if a caveman ate it, so should you,"
For humans, ancient or modern, the paleo diet is the optimum diet, says Dr. Loren Cordain, a professor in the health department of Colorado State University and author of The Paleo Diet, The Paleo Answer, and The Paleo Diet for Athletes.
Genetically we have not been able to adapt to our modern food choices -- i.e., the so-called Western diet, which is largely based on processed foods and laden with fat, salt and sugar -- he says. Consequently, we are now plagued with diseases that are caused by our acting against our nature. The solution would be to dispense with most, if not all, man-made foods, especially carbohydrates and dairy products. Instead, followers are encouraged to eat meats and seafood (wild caught), as well as certain vegetables and fruits, as long as they can be found in their original, unmodified state. Intermittent fasting is also recommended.
Some nutrition experts and biologists, however, are skeptical of these restrictions.
The paleo diet is basically a fantasy, according to Dr. Marlene Zuk, a professor of ecology, evolution and behavioral science at the University of Michigan [California?], who gave an interview on the subject to the German news magazine Der Spiegel.
"Its supporters assume that, at a certain point in time, our ancestors were perfectly adapted to their environment. But those conditions presumably never existed," she said. Besides that, "our modern food products are well removed from their wild ancestors. They have been extremely modified and, as a result, are more calorie-rich, easier to ship, or simply better-tasting than the original. So, even if we wanted to, we couldn't live exactly the way our ancestors did," said Dr. Zuk. “‘Paleofantasies’ call to mind a time when everything about us—body, mind, and behavior—was in sync with the environment…but no such time existed," Zuk wrote in her book. "We and every other living thing have always lurched along in evolutionary time, with the inevitable trade-offs that are a hallmark of life.”
As far as the health benefits of the paleo diet are concerned, they are so far undetermined. Some studies have linked the regimen to reducing blood pressure, LDL (bad) cholesterol, and triglycerides (a fatty substance in the arteries that can increase the risk of heart disease and stroke). That doesn't mean there are no benefits to be had from the paleo diet. Most nutritionists consent that the Paleo diet gets at least one thing right—cutting down on processed foods that have been highly modified from their raw state through various methods of preservation. Examples include white bread and other refined flour products, artificial cheese, certain cold cuts and packaged meats, potato chips, and sugary cereals. Such processed foods often offer less protein, fiber and iron than their unprocessed equivalents, and some are packed with sodium and preservatives that may increase the risk of heart disease and certain cancers. But the Paleo diet bans more than just highly processed junk foods—in its most traditional form, it prohibits any kind of food unavailable to stone age hunter–gatherers, including dairy rich in calcium, grains replete with fiber, and vitamins and legumes packed with protein.
The logic behind the Paleo diet fails in several ways: by the emphasis of one particular slice of our evolutionary history; by insisting that we are biologically identical to stone age humans; and by denying the benefits of some of our more modern methods of eating. A proponent of Paleo diet, fitness author Mark Sisson asserts that "while the world has changed in innumerable ways in the last 10,000 years (for better and worse), the human genome has changed very little and thus only thrives under similar conditions." This is simply not true. In fact, this reasoning misconstrues how evolution works. If humans and other organisms could only thrive in circumstances similar to the ones their predecessors lived in, life would not have lasted very long.
Several examples of recent and relatively speedy human evolution underscore that our anatomy and genetics have not been set in stone since the stone age. Within a span of 7,000 years, for instance, people adapted to eating dairy by developing lactose tolerance. Usually, the gene encoding an enzyme named lactase—which breaks down lactose sugars in milk—shuts down after infancy; when dairy became prevalent, many people evolved a mutation that kept the gene turned on throughout life. Likewise, the genetic mutation responsible for blue eyes likely arose between 6,000 and 10,000 years ago. And in regions where malaria is common, natural selection has modified people's immune systems and red blood cells in ways that help them resist the mosquito-borne disease; some of these genetic mutations appeared within the last 10,000 or even 5,000 years. The organisms with which we share our bodies have evolved even faster, particularly the billions of bacteria living in our intestines. Our gut bacteria interact with our food in many ways, helping us break down tough plant fibers, but also competing for calories. We do not have direct evidence of which bacterial species thrived in Paleolithic intestines, but we can be sure that their microbial communities do not exactly match our own.
Even if eating only foods available to hunter–gatherers in the Paleolithic made sense, it would be impossible. Just about every single species commonly consumed today—whether a fruit, vegetable or animal—is drastically different from its Paleolithic predecessor. In most cases, we have transformed the species we eat through artificial selection: we have bred cows, chickens and goats to provide as much meat, milk and eggs as possible and have sown seeds only from plants with the most desirable traits—with the biggest fruits, plumpest kernels, sweetest flesh and fewest natural toxins. Cabbage, broccoli, cauliflower, Brussels sprouts and kale are all different cultivars of a single species, Brassica oleracea; generation by generation, we reshaped this one plant's leaves, stems and flowers into wildly different arrangements, the same way we bred dachshunds and great danes out of a single wolf species. Corn was once a straggly grass known as teosinte and tomatoes were once much smaller berries. And the wild ancestors of bananas were rife with seeds.
We cannot time travel and join our Paleo ancestors in a meal but we do have the advantage of studying surviving hunter-gatherer societies.
Anthropologist William Leonard of Northwestern University wrote in Scientific American in 2002, "Our species was not designed to subsist on a single, optimal diet. What is remarkable about human beings is the extraordinary variety of what we eat. We have been able to thrive in almost every ecosystem on the Earth, consuming diets ranging from almost all animal foods among populations of the Arctic to primarily tubers and cereal grains among populations in the high Andes.”
Hunter–gatherers in the Paleolithic hunted and gathered because they had to. Paleo dieters attempt to eat like hunter–gatherers because they want to.
Taken from here
For humans, ancient or modern, the paleo diet is the optimum diet, says Dr. Loren Cordain, a professor in the health department of Colorado State University and author of The Paleo Diet, The Paleo Answer, and The Paleo Diet for Athletes.
Genetically we have not been able to adapt to our modern food choices -- i.e., the so-called Western diet, which is largely based on processed foods and laden with fat, salt and sugar -- he says. Consequently, we are now plagued with diseases that are caused by our acting against our nature. The solution would be to dispense with most, if not all, man-made foods, especially carbohydrates and dairy products. Instead, followers are encouraged to eat meats and seafood (wild caught), as well as certain vegetables and fruits, as long as they can be found in their original, unmodified state. Intermittent fasting is also recommended.
Some nutrition experts and biologists, however, are skeptical of these restrictions.
The paleo diet is basically a fantasy, according to Dr. Marlene Zuk, a professor of ecology, evolution and behavioral science at the University of Michigan [California?], who gave an interview on the subject to the German news magazine Der Spiegel.
"Its supporters assume that, at a certain point in time, our ancestors were perfectly adapted to their environment. But those conditions presumably never existed," she said. Besides that, "our modern food products are well removed from their wild ancestors. They have been extremely modified and, as a result, are more calorie-rich, easier to ship, or simply better-tasting than the original. So, even if we wanted to, we couldn't live exactly the way our ancestors did," said Dr. Zuk. “‘Paleofantasies’ call to mind a time when everything about us—body, mind, and behavior—was in sync with the environment…but no such time existed," Zuk wrote in her book. "We and every other living thing have always lurched along in evolutionary time, with the inevitable trade-offs that are a hallmark of life.”
As far as the health benefits of the paleo diet are concerned, they are so far undetermined. Some studies have linked the regimen to reducing blood pressure, LDL (bad) cholesterol, and triglycerides (a fatty substance in the arteries that can increase the risk of heart disease and stroke). That doesn't mean there are no benefits to be had from the paleo diet. Most nutritionists consent that the Paleo diet gets at least one thing right—cutting down on processed foods that have been highly modified from their raw state through various methods of preservation. Examples include white bread and other refined flour products, artificial cheese, certain cold cuts and packaged meats, potato chips, and sugary cereals. Such processed foods often offer less protein, fiber and iron than their unprocessed equivalents, and some are packed with sodium and preservatives that may increase the risk of heart disease and certain cancers. But the Paleo diet bans more than just highly processed junk foods—in its most traditional form, it prohibits any kind of food unavailable to stone age hunter–gatherers, including dairy rich in calcium, grains replete with fiber, and vitamins and legumes packed with protein.
The logic behind the Paleo diet fails in several ways: by the emphasis of one particular slice of our evolutionary history; by insisting that we are biologically identical to stone age humans; and by denying the benefits of some of our more modern methods of eating. A proponent of Paleo diet, fitness author Mark Sisson asserts that "while the world has changed in innumerable ways in the last 10,000 years (for better and worse), the human genome has changed very little and thus only thrives under similar conditions." This is simply not true. In fact, this reasoning misconstrues how evolution works. If humans and other organisms could only thrive in circumstances similar to the ones their predecessors lived in, life would not have lasted very long.
Several examples of recent and relatively speedy human evolution underscore that our anatomy and genetics have not been set in stone since the stone age. Within a span of 7,000 years, for instance, people adapted to eating dairy by developing lactose tolerance. Usually, the gene encoding an enzyme named lactase—which breaks down lactose sugars in milk—shuts down after infancy; when dairy became prevalent, many people evolved a mutation that kept the gene turned on throughout life. Likewise, the genetic mutation responsible for blue eyes likely arose between 6,000 and 10,000 years ago. And in regions where malaria is common, natural selection has modified people's immune systems and red blood cells in ways that help them resist the mosquito-borne disease; some of these genetic mutations appeared within the last 10,000 or even 5,000 years. The organisms with which we share our bodies have evolved even faster, particularly the billions of bacteria living in our intestines. Our gut bacteria interact with our food in many ways, helping us break down tough plant fibers, but also competing for calories. We do not have direct evidence of which bacterial species thrived in Paleolithic intestines, but we can be sure that their microbial communities do not exactly match our own.
Even if eating only foods available to hunter–gatherers in the Paleolithic made sense, it would be impossible. Just about every single species commonly consumed today—whether a fruit, vegetable or animal—is drastically different from its Paleolithic predecessor. In most cases, we have transformed the species we eat through artificial selection: we have bred cows, chickens and goats to provide as much meat, milk and eggs as possible and have sown seeds only from plants with the most desirable traits—with the biggest fruits, plumpest kernels, sweetest flesh and fewest natural toxins. Cabbage, broccoli, cauliflower, Brussels sprouts and kale are all different cultivars of a single species, Brassica oleracea; generation by generation, we reshaped this one plant's leaves, stems and flowers into wildly different arrangements, the same way we bred dachshunds and great danes out of a single wolf species. Corn was once a straggly grass known as teosinte and tomatoes were once much smaller berries. And the wild ancestors of bananas were rife with seeds.
We cannot time travel and join our Paleo ancestors in a meal but we do have the advantage of studying surviving hunter-gatherer societies.
Anthropologist William Leonard of Northwestern University wrote in Scientific American in 2002, "Our species was not designed to subsist on a single, optimal diet. What is remarkable about human beings is the extraordinary variety of what we eat. We have been able to thrive in almost every ecosystem on the Earth, consuming diets ranging from almost all animal foods among populations of the Arctic to primarily tubers and cereal grains among populations in the high Andes.”
Hunter–gatherers in the Paleolithic hunted and gathered because they had to. Paleo dieters attempt to eat like hunter–gatherers because they want to.
Taken from here
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