The Paleolithic Diet, Part I: A New Look at Our Oldest Diet

According to Duke University and the CDC, 42% of Americans will be obese by 2030. Despite advances in health care, the number of people with diabetes, heart disease, stroke, Alzheimer’s disease, and other modern diseases continues to increase. What is going wrong?

Some attribute the increase in obesity, an underlying factor in many of the modern diseases, to a lack of will power, a puzzling argument that fails to explain the increasing body mass over the past three decades. Others blame easy availability of food and lack of exercise: we take in too many calories and don’t burn enough. The simplistic solution proposed: eat less and exercise more. While our sedentary lifestyle contributes to obesity, the real culprit is low-quality fuel. We chose, and are surrounded by, low quality foods. Physical anthropologist Gary J. Sawyer puts it simply:

“We do not know how to eat properly. We feed ourselves, but we fail to give ourselves proper nutrition.”

A new look at our oldest diet

Fortunately, we are beginning to understand the underlying factors triggering modern diseases, among them, chronic inflammation. According to the December 2010 Science journal:

“Over the past decade it has become widely accepted that inflammation is a driving force behind chronic diseases that will kill nearly all of us. Cancer. Diabetes and obesity. Alzheimer’s disease. Artherosceloris. Here, inflammation wears a grim mask, shedding its redeeming features making sick people sicker.”

The typical Western diet is inflammatory; the diet of our Paleolithic ancestors was non-inflammatory. While the agricultural revolution around 10,000 years ago, and animal husbandry a few thousand years later, led to modern civilization, they also began to undermine our health. We became shorter and developed bone mineral disorders and nutritional deficiencies. We became less robust and developed smaller jaws. As summarized in a recent study: “Early Farmers Were Sicker and Shorter Than Their Forager Ancestors.”

What is the Paleo diet?

Interest in the ancestral human diet is growing. For over 180,000 years before agriculture, our diet was simple, yet more varied than the modern diet. Loren Cordain, professor of Health & Exercise Science at Colorado State University and one of the world’s leading experts on Paleolithic nutrition, has analyzed the diets of over 200 hunter-gatherer societies and described the ancestral diet in two recent books: The Paleo Diet and The Paleo Answer.

Our pre-agricultural ancestors “ate no dairy,” which triggers the immune system and causes a similar rise in insulin as white bread. Except in conditions of starvation they did not eat grains. Unlike ruminants, humans can’t ferment grains and only extract significant energy from grains when processed.

The role of grains as a cause of inflammation is coming under greater scrutiny. While gluten allergy and sensitivity are recognized conditions, only recently are we recognizing that gluten can affect the nervous system and in some people cause gluten ataxia, gluten spinal inflammation, and gluten neuropathy.

The non-inflammatory Paleolithic diet consists of varying amounts of lean meats, fish, seafood, vegetables, fruits, tubers, nuts and berries and significantly reduces, or eliminates, grains and dairy.

Vegetables are “rich in a long list of nutrients,” and, per calorie, non-starchy vegetables have seven times the fiber of whole grain cereals. The typical modern diet contains “a measly 8 grams” of fiber “compared to 47 grams on the Paleo Diet.”

Fruits are “almost as nutrient dense as vegetables.” Dr. Cordain believes you “have to consume huge amounts to get much fructose.”

Fish and shellfish are rich in fatty acids crucial to nervous system function. It is probably not a coincidence the first signs of human consciousness 70,000 years ago were produced by ancestors living next to the sea and thriving on a diet rich in fish and seafood.

Meats have twice the “thermic effect” of fat or carbohydrate (they increase metabolic rate) and have the highest “satiating value” (satisfy hunger). Meats increase good HDL cholesterol, are the best source of iron, B12, and zinc, and are rich in the building blocks of enzymes and brain neurotransmitters.

The right fats are essential to human health. Unfortunately, the typical diet tilts heavily to saturated fats. Cordain’s laboratory found “that despite their high meat content, modern-day Paleo diets actually contain lower quantities of saturated fats than are found in the typical U.S. diet. Two-thirds of all of the saturated fats that Americans consume come from processed foods and dairy products.”

(Article initially published in Living Well magazine)

Part 2 will review the developing medical evidence favoring the Paleolithic diet.

Do hunter-gatherers really burn more calories per day?

Daily activity of the Hadza. Image: Andreas LedererI often see persons in the office with neurological complaints such as headaches, dizziness, difficulty with memory and thinking, or alterations in mood that also have a BMI (Body Mass Index) in the obese category. A common reason offered for not being able loose weight is their inability to exercise.

Conventional wisdom holds that hunter-gathers maintain a normal weight through a combination of the Paleolithic diet and an active lifestyle that burns more calories. According to a new multi-institutional study, Hunter-Gatherer Energetics and Human Obesity published in the July 25 of Plos ONE, this conventional wisdom seems to be incorrect. As described by Science Codex:

The research team behind the study, led by Herman Pontzer of Hunter College in New York City, along with David Raichlen of the University of Arizona and Brian M. Wood of Stanford measured daily energy expenditure (calories per day) among the Hadza, a population of traditional hunter-gatherers living in the open savannah of northern Tanzania. Despite spending their days trekking long distances to forage for wild plants and game, the Hadza burned no more calories each day than adults in the U.S. and Europe. The team ran several analyses accounting for the effects of body weight, body fat percentage, age, and gender. In all analyses, daily energy expenditure among the Hadza hunter-gatherers was indistinguishable from that of Westerners. The study was the first to measure energy expenditure in hunter-gatherers directly; previous studies had relied entirely on estimates.

However, this does not mean you shouldn’t exercise:

The authors emphasize that physical exercise is nonetheless important for maintaining good health. In fact, the Hadza spend a greater percentage of their daily energy budget on physical activity than Westerners do, which may contribute to the health and vitality evident among older Hadza. Still, the similarity in daily energy expenditure between Hadza hunter-gatherers and Westerners suggests that we have more to learn about human physiology and health, particularly in non-Western settings.

Bottom line: The type of food consumed matters tremendously! The key factor in loosing weight is what you select at the grocery store or restaurant! Low-grade chronic inflammation resulting from the modern diet and the impact of modern foods on the brain's regulation of eating behavior are the prime suspects in the obesity epidemic. Returning to the ancestral human diet is the most powerful tool for reclaiming a normal weight.

Related Links

• An "Insight of the Decade": Chronic inflammation kills
• Inflammation impairs frontal lobe brain function 
• Paleolithic Nutrition: Chronic Inflammation
• Getting fatter on the typical Western diet
• New hypothesis: Acellular carbohydrates promote obesity
• “Fascinating insight”: Inflamed cells circulating in bloodstream
• Paleolithic Nutrition: Diabetes and the Modern Diet
• Success Stories 

Quote: Adiposity causes inflammation of the hypothalamus

Adiposity is associated with chronic low-grade systemic inflammation and increased inflammation in the hypothalamus, a key structure in feeding behavior.

Obesity-mediated inflammation may damage the brain circuit that regulates food intake. Brain Res. 2011 Feb 10;1373:101-9. 

In other words, excess fatty tissue in obesity harms the hypothalamus, the brain structure that regulates feeding behaviour, and makes it more difficult to control overeating. Through inflammation, excess fatty tissue takes control. The solution, a non-inflammatory diet such as the Paleo diet. 

Related links:

• An "Insight of the Decade": Chronic inflammation kills
• Inflammation impairs frontal lobe brain function
• Brain Health: Omega-3 fatty acids reduce anxiety
• The microenvironment: “… an entirely new way of thinking about cancer”

Paleolithic Nutrition: Chronic Inflammation

By John Michael

It was Monday night, and I had just finished packing my bags. With everyone else in the house asleep, I had nothing to do but think about my flight the next day. I would be leaving Denver at seven AM, and arriving in my Midwestern hometown sometime in the early afternoon.

I love eating Paleo, but every now and then, especially late at night, I succumb to the lure of other foods, processed foods… industrial foods.

This time it was my nerves. I get anxiety when I travel, and ever since I was a little boy, I’ve used junk food to calm myself. Normally, I eat well, but when anxiety appears, old habits follow. That’s how I ended up in front of my parent’s open freezer at midnight, with its pale light and steaming air pouring over me. 

Tuesday morning I woke with a tingling rawness in my gums. I’d fallen asleep without brushing my teeth; an empty pint of ice cream was on my bedside table.

After brushing, the gum inflammation subsided, but I was left wondering, Had this always happened before I went Paleo? Or had I just become sensitive?

Then I thought of the other foods that made me feel inflamed. When I ate tomatoes, my entire body tingled slightly. Not to mention what wheat products did to my GI tract. John Michael’s recipe for farts and bloating: just add grain.

Consideration of my irritated gums sobered me. Had I always had these inflammatory reactions to food but lacked the discernment to notice? Had my body been chronically inflamed by the profligate diet of my early years? 

The Search Begins

I’d heard about chronic inflammation on the news, knew it as a silent killer that could secretly spread through my body. But I’d never taken the time to actually learn how it occurred; I’d only heard enough to create a phantom in my mind, a shadowy figure that fear inflated until it loomed over me.

Better, I thought then, to just ignore it.

But I’m not a young man anymore; the damage I do to my body today no longer miraculously disappears tomorrow. Compelled by my irritated gums, I decided to put aside my fear and face the specter of chronic inflammation.

The Mechanism of Inflammation

When a splinter enters my thumb, it incites inflammation. Nearby cells release chemicals, called inflammatory mediators, which activate an autoimmune reaction. In response, blood vessels dilate, filling the damaged area with fluids. This causes swelling and redness, and isolates the injured tissue.

Then immune cells arrive to consume cellular debris and pathogens. When no further damage occurs, the release of inflammatory mediators subsides, and the process of acute inflammation ends.

Unless another splinter pierces my thumb, in which case inflammation begins anew. And if splinters constantly stick my thumb, then it never stops. With irritation never ceasing, cells consistently release inflammatory mediators, and acute inflammation becomes chronic 

Chronic Inflammation Revealed 

Our own cells are often the victims of these responses. The persistent immune assault can wear them down, reducing their effectiveness and increasing the likelihood of damage and death. It’s logical then that chronic inflammation should play a role in so many diseases.

It can cause cancer by damaging cellular DNA, thus predisposing cells to dangerous mutations. And inflammation also aids in the growth of tumors, often hijacked by cancer to assist in its own development. It even appears in Alzheimer’s, with the brains of sufferers displaying all the signs of a chronic inflammatory response. 

One study cited by Dr. John in a recent talk he gave, “New Research on the Role of Nutrition on Neurological Function,” suggests, “Depression belongs to the spectrum of inflammatory and degenerative disorders.” Another study from his presentation notes that when high levels of inflammatory mediator C-reactive protein were found in stroke patients, chances were high they would also have problems with planning, decision-making, and self-control.

The agents of chronic inflammation are many, from lifestyle choices like smoking and diet, to other factors like repeated infection. Obesity incites it, as fat cells leak and rupture, exciting an autoimmune response. Antibiotics, chemicals, and even undigested food can cause it as well.

Avoiding Inflammation

The picture these studies paint is one of the human body as an intricate collection of delicately balanced components, easily destabilized by the introduction of toxic elements.

We can maintain this delicate balance by making good choices, like avoiding cigarettes and other tobacco products. Eating Paleo can re-establish our omega-3 to omega-6 ratio, which is at an unhealthy 1 to 15 in the Standard American Diet.

Spices like turmeric and ginger have anti-inflammatory properties; toss some on your next meal. The probiotics found in yogurt can reduce inflammation by maintaining a healthy gut; if you avoid dairy, then supplements exist to meet your needs. Additionally, keeping a healthy body weight prevents inflammation caused by obesity, and reducing stress helps as well.