Can You Prevent Weight Gain And 21st Century Health Problems By Eating Like Our Ancestors Did?
This is the prerequisite for the Paleo Diet, which is based on the Paleolithic, which stretched 2.6 million to 12,000 years ago – before the advent of agriculture and the domestication of animals.
Some paleo dieters believe that humans are genetically adapted to eat a particular way – one closer to how early people ate. This view is rooted in the evolutionary discordance hypothesis that human evolution stopped about 50,000 years ago. In other words, our Stone Age bodies are not suited to our modern diets of convenience and carbohydrates, and this mismatch makes us fat and sick.
While eating like a caveman or cave woman isn't easy, the paleo jump is said to bring a number of health benefits – from weight loss to clearer skin, to improved mood and better sleep. But like many health and wellness fads, researchers say the health benefits of paleo are probably too good to be true.
Unfortunately, scientists haven't found much evidence to support the health benefits of the paleo diet beyond weight loss. Other claims were not investigated at all. However, research has found that following a paleo diet may be unhealthy for some people, especially those who are concerned with heart and kidney health.
But there is another mammoth in the room: Even paleolithic people did not eat "paleo". Numerous anthropological studies have found that the interpretations of popular diets of how people from the Paleolithic ate are rather imprecise.
"(With) old diets, people only ate what was available to them. With the current globalized food system, we now have access to more types of food, which complicates this approach," says Colleen Rauchut Tewksbury, a senior researcher and bariatric scientist Program Manager at the University of Pennsylvania. She is also the spokesperson for the Academy of Nutrition and Dietetics.
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The modern paleo diet
According to data from Google Trends, “Paleo” was the most searched diet in 2013. In recent years, diets like keto, intermittent fasting, and the carnivore diet Paleo have dropped out of the top tier. However, survey data from 2018 showed that around 3 million Americans were still following a version of the Paleo Diet.
It is also sometimes referred to as the Paleolithic Diet, Stone Age Diet, Hunter-Gatherer Diet, or Caveman Diet. Whole30, a 30-day program based on the Paleo Diet, has also become a popular way to supposedly "reset" the body after a pampering vacation season.
But whatever you put it, the interest in old diets isn't new. In the 1970s, an American gastroenterologist named Walter L. Voegtlin promoted a meat-oriented "Stone Age" diet for optimal health. Voegtlin is widely regarded as the pioneer of the modern paleo diet and was the first to write a book about it. But his ideas never found widespread support, which may not come as a surprise given some extreme and unsavory views from Voegtlin – such as promoting the mass slaughter of dolphins and eugenics.
Since then, other alleged health gurus have helped bring Paleo out of the cave into the mainstream. Original food feels at home in our current era of romanticizing the health wisdom and habits of the past.
But before you continue sipping bone broth, it might be a good idea to consider what real prehistoric people actually ate.
What did our Paleolithic ancestors eat?
While people who lived in the Paleolithic Age would have meticulously hunted and gathered their own food, modern day followers of the diet can easily get into their cars and zoom to the nearest grocery store to find top paleo essentials on their shopping list. There they can load up all of the meat, fish, eggs, fruits, non-starchy vegetables and nuts that they want. However, dairy products, legumes, cereals, added sugars, alcohol, coffee, and processed foods should be avoided. Some versions of the Paleo Diet are stricter than others.
However, one nuance that modern diet fails to take into account is that hunters and gatherers differed significantly in terms of the foods they consume. Different groups of early humans lived in very different climates and landscapes. People just ate what was available wherever it was.
“Homo sapiens occupied every niche on the planet (approximately) 100,000 years ago. We were very adaptable, ”says Jennie Brand-Miller, Professor of Nutrition at the University of Sydney. "There were hunters and gatherers in high latitudes who ate mostly animal food and very little vegetable food … and there was the opposite (those who ate) a lot of vegetable food and only a small animal food (protein)."
"Interestingly, there were no vegan hunters and gatherers," she says.
Eating meat is often emphasized in anthropology only because slaughtered animal bones are often better preserved and are more likely to be discovered than evidence of vegetable meals. Based on what was revealed, early humans didn't seem terribly picky eaters. You probably ate insects. They didn't turn their noses to elephant brains. They ate starchy tubers. They ate oats, processed by hand.
One thing is certain, however: our ancestors certainly didn't eat bacon or chocolate. These indulgences appeared on the food scene much later in history, but are sometimes recommended in the paleo-diet literature. (But it's pretty safe to say that our paleo ancestors would have eaten bacon or chocolate if they had the chance.)
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What are people adapted to eating?
The idea that we should be on a special diet because our genes are still in the Stone Age is not entirely correct. As cultures change over time, so do our genes. Brand-Miller says there are some genetic adaptations to modern diets that illustrate this.
One of the best examples concerns milk and the prevalence of lactose intolerance. For most of our species' history, there has been no way of digesting milk after infancy. Adults lacked lactase, the enzyme needed to break down lactose into simpler sugars that the intestines can absorb. When humans began domesticated cattle about 10,000 years ago, they relied on dairy products as a source of food. Over time, these groups developed a genetic mutation to bring lactase into adulthood. But because dairy products were not a traditional part of the diet everywhere, many descendants of these groups today lack this genetic mutation.
According to Brand-Miller, people's abilities to process other foods also differ. People with genetic ties to regions that have been greatly strengthened in the past tend to have more copies of the gene, which is related to higher production of salivary amylase – an enzyme that breaks down carbohydrates. This makes East Asians in particular more efficient at digesting starchy foods. Brand-Miller also says that fruit was not part of the traditional arctic diet. It is therefore not surprising that people of Inuit descent are more likely to not have sucrase, the enzyme that processes sucrose, a type of sugar.
Some people who do not have adequate amounts of certain digestive enzymes can still consume small amounts of these foods with no ill effects, says Brand-Miller. These differences aside, humans are generally well suited to eating almost anything in front of them, which is perhaps one of the secrets to the success of our species.
"People always have and probably always will eat a wide variety of foods, depending on the culture and the products available," says Melyssa Roy, a public health researcher at the University of Otago in New Zealand.
Is the Paleo Diet Healthy?
The health claims related to the paleo diet are as controversial as the old menus themselves. Typically, the modern paleo diet is high in protein and low in carbohydrates. Paleo often gets a bad rap for being so restrictive and not allowing consumption of foods like legumes, whole grains, and dairy products.
“Diet has many gray areas and many diets like this leave little room for flexibility or individualization,” says Rauchut Tewksbury.
Because Paleo has not been extensively studied, little is known about the long-term benefits and potential risks. But if weight loss is your main reason for considering the paleo diet, there is some evidence to suggest that it works.
For example, Roy and her colleagues compared the weight loss results of 250 obese people following one of three diets: intermittent fasting, Mediterranean, and Paleo. After 12 months all groups lost weight – but Paleo was the last to enter. Paleo dieters lost an average of 4 pounds, compared to a 6 pound loss on the Mediterranean diet and nearly 9 pounds on intermittent fasts. In general, it was easiest for participants to stick to the Mediterranean Diet, which is an important part of maintaining weight loss over time.
But if rapid weight loss is your goal, the paleo diet has its merits.
"In the short term, low-carbohydrate paleo diets are associated with greater satiety and faster weight loss," says Brand-Miller.
A two-year randomized and controlled study tracked 70 postmenopausal Swedish women who were overweight. Some participants were placed on a paleo diet that included lean meat, fish, eggs, vegetables, fruits, berries, and nuts. Other participants received a diet according to the rdic Nutrition Recommendations (NNR), the common nutritional recommendations for rthern European countries. The NNR contains less protein and fat, but more carbohydrates than the Paleo diet.
Six months later, the paleo group lost more weight than those after the NNR. Paleo dieters lost an average of 13 pounds compared to 5 pounds with NNR. But after 24 months, the difference in weight loss between the two diets was less pronounced. Both groups showed similar improvements in blood pressure and cholesterol. Interestingly, participants' triglyceride levels dropped more sharply during the paleo diet. High levels of triglycerides – a type of fat in the blood – have been linked to heart disease.
However, this does not necessarily mean that the Paleo Diet is heart healthy. According to Brand-Miller, several studies have linked low-carb diets with higher death rates, particularly from heart disease. In addition, mouse studies have shown that diets high in carbohydrates increase life expectancy. Maybe the reason lies in our microbiomes.
One study compared the blood counts of 44 paleo dieters to 47 people following a diet based on Australia's national health recommendations. Among paleo-dieters, the researchers found elevated levels of a compound called trimethylamine N-oxide, which is linked to heart problems. In their work, the researchers stated that high levels of this compound could be due to a lack of whole grains in the paleo diet. Bacteria in the gut produce trimethylamine-N-oxide while digesting meat. However, consuming whole grains increases the production of beneficial intestinal bacteria, which appears to counteract the harmful compound.
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Saturated fat could be another cause for concern about the Paleo Diet. Dietary fats are generally not as demonized today as they were in the 1990s. But saturated fat isn't entirely clear. Decades of research have linked saturated fat consumption to elevated LDL cholesterol levels (the bad kind), which has been shown to increase your risk of heart disease.
“The evidence is contradicting whether high levels of saturated fat associated with this type of diet are harmful. For some people, it may be better to avoid high amounts of animal fat, especially if they are still on a standard diet. A strict paleo diet eliminates dairy products and there can be calcium intake concerns, too, ”says Roy.
Diets high in protein have also been linked to kidney problems. It is not clear whether this applies to people with normally functioning kidneys. Filtering excess protein from the blood can put additional strain on organs and further impair their function in people with kidney problems.
But the idea that paleo must be abundant in meat might be a misnomer at first.
"(Paleo) is more about eating foods in their natural state," says Roy.
Brand-Miller says there are healthier approaches to paleo. For example, with lots of fruit and vegetables – including carbohydrates. Plant-based foods can add nutrients, fiber, flavor, and variety to the diet. And they also help you live longer.
If the paleo diet does one thing right, it is the anti-processed food stance. Highly refined, ultra-processed foods now make up more than half of all calories consumed and 90 percent of additional sugar intake in the US – increasing the risk of weight gain and various health problems. But it's not about paleo or bust.
“Ultimately, the best way to eat for your health is through change you can keep up with. Most people know what to do: limit calories, eat fruits, vegetables, whole grains, and lean protein. The challenge is how to do it, ”says Rauchut Tewksbury. “There are many ways that people can achieve this. The key is figuring out which one is best for you as an individual to keep up with. "