The Beneficial Effects of a Paleolithic Diet on Type 2 Diabetes and Other Risk Factors for Cardiovascular Disease
Source:J Diabetes Sci Technol. 2009 November; 3(6): 1229–1232.
What Is a Paleolithic Diet?
The Paleolithic diet is also referred to as the caveman diet, Stone Age diet, and hunter–gatherer diet. This diet consists of foods that are assumed to have been available to humans prior to the establishment of agriculture. The principal components of this diet are wild-animal source and uncultivated-plant source foods, such as lean meat, fish, vegetables, fruits, roots, eggs, and nuts. The diet excludes grains, legumes, dairy products, salt, refined sugar, and processed oils, all of which were unavailable before humans began cultivating plants and domesticating animals.
How Does a Paleolithic Diet Differ from a Diabetes Diet?
In the Jönsson study, the diabetes diet was intended to deliver meals with increased intake of vegetables, root vegetables, dietary fiber, whole-grain bread and other whole-grain cereal products, and fruits and berries and decreased intake of total fat with more unsaturated fat.1 In that study, the majority of dietary energy in the diabetes diet came from carbohydrates found in foods naturally rich in carbohydrate and dietary fiber. The concepts of glycemic index and varied meals were taught with a visual meal-planning plate model.
In the Jönsson study, the Paleolithic diet was lower in cereals, dairy products, potatoes, beans, and bakery foods but higher in fruits, vegetables, meat, and eggs compared to the diabetes diet. The Paleolithic diet worked out to be lower in total energy, energy density, carbohydrate, dietary glycemic load, fiber, saturated fatty acids, and calcium but higher in unsaturated fatty acids, dietary cholesterol, and several vitamins and minerals.1
What Effect Does a Paleolithic Diet Have on Type 2 Diabetes?
The Jönsson study was the first to assess the potential benefit of the Paleolithic diet compared to a diabetes diet for patients with T2DM.1 This pilot crossover study evaluated 13 subjects with T2DM on oral agent therapy. Subjects consumed, for three months each, either a Paleolithic diet followed by a diabetes diet or the same two diets in the opposite order for three months each. Compared to the diabetes diet, the Paleolithic diet resulted in statistically significant lower mean values of hemoglobin A1c, triglycerides, diastolic blood pressure, weight, body mass index, and waist circumference, while mean values for high-density lipoprotein were higher. The larger decrease of fasting plasma glucose following the Paleolithic diet nearly reached statistical significance, and systolic blood pressure also tended to decrease more following the Paleolithic diet. Ingestion of a Paleolithic diet (compared to a diabetes diet) did not result in a significant reduction in the area under the curve between 0 and 120 min for glucose during a 75 g oral glucose tolerance test, and that measure had been a prespecified endpoint.
The impact of this study was limited by its small size, which did not recruit the number of participants needed according to the prestudy power calculation. The investigators decided to terminate the study early because recruitment had failed to yield any new participants for more than 6 months before termination. The subjects were not blinded as to which diet they were ingesting, but the investigators told them both diets were healthy and that it was unknown whether either diet was superior.