A Paleolithic diet confers higher insulin sensitivity, lower C-reactive protein and lower blood pressure than a cereal-based diet in domestic pigs

http://www.nutritionandmetabolism.com/content/3/1/39

Research

A Paleolithic diet confers higher insulin sensitivity, lower C-reactive
protein and lower blood pressure than a cereal-based diet in domestic pigs
Tommy Jonsson , Bo Ahren , Giovanni Pacini , Frank Sundler , Nils Wierup ,
Stig Steen , Trygve Sjoberg , Martin Ugander , Johan Frostegard , Leif
Goransson and Staffan Lindeberg

Nutrition & Metabolism 2006, 3:39 doi:10.1186/1743-7075-3-39

Published 2 November 2006


Background
A Paleolithic diet has been suggested to be more in concordance with human
evolutionary legacy than a cereal based diet. This might explain the lower
incidence among hunter-gatherers of diseases of affluence such as type 2
diabetes, obesity and cardiovascular disease. The aim of this study was to
experimentally study the long-term effect of a Paleolithic diet on risk
factors for these diseases in domestic pigs. We examined glucose tolerance,
post-challenge insulin response, plasma C-reactive protein and blood
pressure after 15 months on Paleolithic diet in comparison with a cereal
based swine feed.

Methods
Upon weaning twenty-four piglets were randomly allocated either to cereal
based swine feed (Cereal group) or cereal free Paleolithic diet consisting
of vegetables, fruit, meat and a small amount of tubers (Paleolithic group).
At 17 months of age an intravenous glucose tolerance test was performed and
pancreas specimens were collected for immunohistochemistry. Group
comparisons of continuous variables were made by use of the t-test. P<0.05
was chosen for statistical significance. Simple and multivariate
correlations were evaluated by use of linear regression analysis.

Results
At the end of the study the Paleolithic group weighed 22% less and had 43%
lower subcutaneous fat thickness at mid sternum. No significant difference
was seen in fasting glucose between groups. Dynamic insulin sensitivity was
significantly higher (p=0.004) and the insulin response was significantly
lower in the Paleolithic group (p=0.001). The geometric mean of C-reactive
protein was 82% lower (p=0.0007) and intra-arterial diastolic blood pressure
was 13% lower in the Paleolithic group (p=0.007). In evaluations of
multivariate correlations, diet emerged as the strongest explanatory
variable for the variations in dynamic insulin sensitivity, insulin
response, C-reactive protein and diastolic blood pressure when compared to
other relevant variables such as weight and subcutaneous fat thickness at
mid sternum. There was no obvious immunohistochemical difference in
pancreatic islets between the groups, but leukocytes were clearly more
frequent in sampled pancreas from the Cereal group.

Conclusions
This study in domestic pigs suggests that a Paleolithic diet conferred
higher insulin sensitivity, lower C-reactive protein and lower blood
pressure when compared to a cereal based diet.