Continuing Education Activity

A Paleolithic diet is the modern interpretation of the diet that humans ate during the Paleolithic or “Old Stone Age” era. This period, about 2.5 million years ago, was notable for the anatomic and physiologic changes taking place in humans as they adapted to climate change, learned to cook meat using fire, and began to use stone tools for greater access to food and resources. Anthropologists hold that the diet of our ancestors heavily influenced their neural expansion, increasing brain size, and reduction in their gastrointestinal tract size. This activity describes the benefits and indications of the paleolithic diet and highlights the role of the interprofessional team in ensuring patients eat a healthy diet.

Objectives:

• Identify the function of the paleolithic diet.
• Describe the issues of concern regarding the paleolithic diet.
• Review the clinical significance of a paleolithic diet.
• Outline interprofessional team strategies for improving care coordination and communication to advance patient education about diet and improve outcomes.

Introduction

A Paleolithic diet is the modern interpretation of the diet that humans ate during the Paleolithic or “Old Stone Age” era. This period, about 2.5 million years ago, was notable for the anatomic and physiologic changes taking place in humans as they adapted to climate change, learned to cook meat using fire, and began to use stone tools for greater access to food and resources. Anthropologists hold that the diet of our ancestors heavily influenced their neural expansion, increasing brain size, and reduction in their gastrointestinal tract size.     [1][2][3]

Function

The last one-hundred years have seen a boom of industrialization. While essential for human advancement, industrialization has also given rise to ultra-processed, low cost, readily available foods to sustain a growing population. A consequence of consuming these foods is an increase in the rate of chronic diseases like obesity, diabetes, hypertension, and heart disease. Scientists and laypeople alike have started looking at solutions for these epidemics; alternatives focus not just on medications but the adoption of significant dietary and lifestyle changes. This quest for the "ideal" diet for health and longevity has brought to light several ancient cuisines, and some have been thoroughly studied, like the “Mediterranean Diet.”

The concept of the Paleolithic diet started in the 1970s, and its popularity soared after the publishing of the book The Paleo Diet: Lose Weight and Get Healthy by Eating the Foods You Were Designed to Eat by Loren Cordain in 2002. Since then, the public has shown a tremendous interest in this diet, also called the “cave man diet” or “Stone Age diet.” Many cookbooks have been published claiming to have Paleolithic recipes. The central tenet behind this diet hinges on reverting back to what our prehistoric ancestors ate and rejecting modern-day, processed diet in order to improve our healthcare outcomes. The challenge with this diet however, is that is conflicting versions are presented to the public.

Thankfully, several breakthrough developments in the field of anthropology in the last few years have helped dieters and practitioners better understand the Paleolithic diet. Perhaps one of the most popular misconceptions is that our ancient ancestors were mainly carnivores when, in fact, they mostly ate a plant-based diet. The diet was very broad and heavily influenced by geographical location and food availability.[4][5][6][7]

Scientists and anthropologists have been able to reconstruct this diet based on evidence gathered from archeological remains and by studying modern tribes. In the modern world, about a dozen or so tribes still follow a hunter and gatherer concept. These tribes are located in different parts of the world and in all climatic terrains. The most extensively studied tribe is the Hadza tribe from central Tanzania as the African continent is considered the birthplace of human evolution and where the majority of hominid prehistoric fossils are found. Since the Hadza group resides in the tropical forest, their diet mainly consists of plants, fruits, tubers, and game animals. One of the most popular food groups for them is honey. There also are studies available on some Nordic tribes, who subsist mainly on fish and other seafood.[8][9][10]

Based on these findings, the Paleolithic diet most likely consisted of the following-

• Plants - These included tubers, seeds, nuts, wild-grown barley that was pounded into flour, legumes, and flowers. Since they had discovered fire and stone tools, it is believed that they were able to process and cook these foods.
• Animals - Because they were more readily available, lean small game animals were the main animals eaten. As per some estimates, animal products contributed to only about 3% of the whole diet. Animals had not yet been domesticated so dairy products were most likely not included.
• Seafood - The diet included shellfish and other smaller fish. It was a major component of the diet in coastal regions.
• Insects - A variety of insects and their products, including honey, honeycombs, were eaten. They were a major fallback food. Recently, the interest in edible insects, called entomophagy, has increased. The United Nations released a list of edible insects as an alternative to meat products, as insects can provide similar nutritional benefits. 

Clinical Significance

It is clear that "Stone Age" humans did eat a variety of high-quality foods that were rich in nutrients and fiber. Compared to this diet, modern diets provide much less variety and are loaded with artificial sugars and salt.

Since it is impractical to mimic the exact diet that our Stone Age ancestors ate, we can reasonably take some key foods and adapt them to a modern lifestyle.

Whalen KA, et al. have done studies on the Paleolithic Diet, comparing it to the Mediterranean Diet. In one study of over 2,000 people, participants in each group consumed the list of foods that would fit into each diet pattern. The results were similar in both the groups, although the consumers of a Paleolithic diet decreased their all-cause mortality, decreased oxidative stress, and also decreased mortality from cancers, specifically colon cancers.

Another study by Blomquist C, et al. involved women who were postmenopausal and also overweight. They found that a Paleolithic diet decreased lipogenesis promoting factors, improved insulin sensitivity, and reduced circulating triglycerides.

The Paleolithic diet also has been studied as a supplement for therapeutic management in patients with inflammatory bowel disease. An article by Dr. Jacob Eaton and Dr. Lara Lannotti, strong advocates and pioneers of the Paleolithic Diet, focuses on the mismatch of genomic evolution and the modern day diet. As discussed above, the diet that our ancestors ate has had a major impact on our genetic evolution. Since today's diet no longer contains the same variety and nutrition, however, there is an increase in chronic diseases caused by both “undernutrition” and “overnutrition.” Multiple other smaller-scale studies confirm similar results.

Physicians across the globe have been trying to incorporate healthy dietary and lifestyle habits into the therapeutic regimen of their patients. A Paleolithic diet is certainly a reasonable option for physicians to choose as it advocates healthy eating.

Enhancing Healthcare Team Outcomes

Every few years a new diet is introduced that is thought to be the panacea for good health. Clinicians should not fall into the trap of "diet mania' but should counsel patients to eat a healthy diet low in processed foods, to exercise regularly, and to discontinue smoking and other harmful habits. Like all diets, the paleolithic diet has its pros and cons. This was diet first used by our human ancestors out of necessity, and though it may have been good for the digestive tract it is unknown how it affects human health in the long term. 

Physicians, pharmacists, nurses, and dietitians should all encourage a healthy diet to their patients low in processed foods and higher in fiber, with lean protein sources.