Canibais e Reis

Metabolic and physiologic improvements from consuming a paleolithic, hunter-gatherer type diet (em formato pdf)
Frassetto LA, Schloetter M, Mietus-Synder M, Morris RC Jr, Sebastian A. 1Department of Medicine, University of California San Francisco School of Medicine, San Francisco, CA, USA.

Background:The contemporary American diet figures centrally in the pathogenesis of numerous chronic diseases-’diseases of civilization’. We investigated in humans whether a diet similar to that consumed by our preagricultural hunter-gatherer ancestors (that is, a paleolithic type diet) confers health benefits.Methods:We performed an outpatient, metabolically controlled study, in nine nonobese sedentary healthy volunteers, ensuring no weight loss by daily weight. We compared the findings when the participants consumed their usual diet with those when they consumed a paleolithic type diet. The participants consumed their usual diet for 3 days, three ramp-up diets of increasing potassium and fiber for 7 days, then a paleolithic type diet comprising lean meat, fruits, vegetables and nuts, and excluding nonpaleolithic type foods, such as cereal grains, dairy or legumes, for 10 days. Outcomes included arterial blood pressure (BP); 24-h urine sodium and potassium excretion; plasma glucose and insulin areas under the curve (AUC) during a 2 h oral glucose tolerance test (OGTT); insulin sensitivity; plasma lipid concentrations; and brachial artery reactivity in response to ischemia.Results:Compared with the baseline (usual) diet, we observed (a) significant reductions in BP associated with improved arterial distensibility (-3.1+/-2.9, P=0.01 and +0.19+/-0.23, P=0.05);(b) significant reduction in plasma insulin vs time AUC, during the OGTT (P=0.006); and (c) large significant reductions in total cholesterol, low-density lipoproteins (LDL) and triglycerides (-0.8+/-0.6 (P=0.007), -0.7+/-0.5 (P=0.003) and -0.3+/-0.3 (P=0.01) mmol/l respectively). In all these measured variables, either eight or all nine participants had identical directional responses when switched to paleolithic type diet, that is, near consistently improved status of circulatory, carbohydrate and lipid metabolism/physiology.Conclusions:Even short-term consumption of a paleolithic type diet improves BP and glucose tolerance, decreases insulin secretion, increases insulin sensitivity and improves lipid profiles without weight loss in healthy sedentary humans.European Journal of Clinical Nutrition advance online publication, 11 February 2009; doi:10.1038/ejcn.2009.4.

 

Effects of a short-term intervention with a paleolithic diet in healthy volunteers (em formato pdf)
Osterdahl M, Kocturk T, Koochek A, Wändell PE. Department of Neurobiology, Center for Family and Community Medicine, Care Sciences and Society, Karolinska Institutet, Huddinge, Sweden.

OBJECTIVES: Prevention of cardiovascular diseases by paleolithic or hunter-gatherer diets has been discussed during recent years. METHODS: Our aim was to assess the effect of a paleolithic diet in a pilot study on healthy volunteers during 3 weeks. The intention was to include 20 subjects, of whom 14 fulfilled the study. Complete dietary assessment was available for six subjects. RESULTS: Mean weight decreased by 2.3 kg (P<0.001), body mass index by 0.8 (P<0.001), waist circumference by 0.5 cm (P=0.001), systolic blood pressure by 3 mm Hg (P=0.03) and plasminogen activator inhibitor-1 by 72% (P=0.020). Regarding nutrient intake, intake of energy decreased by 36%, and other effects were also observed, both favourable (fat composition, antioxidants, potassium-sodium rate) and unfavourable (calcium). CONCLUSION: This short-term intervention showed some favourable effects by the diet, but further studies, including control group, are needed. 

 

A Palaeolithic diet improves glucose tolerance more than a Mediterranean-like diet in individuals with ischaemic heart disease (em formato pdf)
Lindeberg S, Jönsson T, Granfeldt Y, Borgstrand E, Soffman J, Sjöström K, Ahrén B. Department of Medicine, Hs 32, University of Lund, SE-221 85, Lund, Sweden.

AIMS/HYPOTHESIS: Most studies of diet in glucose intolerance and type 2 diabetes have focused on intakes of fat, carbohydrate, fibre, fruits and vegetables. Instead, we aimed to compare diets that were available during human evolution with more recently introduced ones. METHODS: Twenty-nine patients with ischaemic heart disease plus either glucose intolerance or type 2 diabetes were randomised to receive (1) a Palaeolithic (’Old Stone Age’) diet (n = 14), based on lean meat, fish, fruits, vegetables, root vegetables, eggs and nuts; or (2) a Consensus (Mediterranean-like) diet (n = 15), based on whole grains, low-fat dairy products, vegetables, fruits, fish, oils and margarines. Primary outcome variables were changes in weight, waist circumference and plasma glucose AUC (AUC Glucose(0-120)) and plasma insulin AUC (AUC Insulin(0-120)) in OGTTs. RESULTS: Over 12 weeks, there was a 26% decrease of AUC Glucose(0-120) (p = 0.0001) in the Palaeolithic group and a 7% decrease (p = 0.08) in the Consensus group. The larger (p = 0.001) improvement in the Palaeolithic group was independent (p = 0.0008) of change in waist circumference (-5.6 cm in the Palaeolithic group, -2.9 cm in the Consensus group; p = 0.03). In the study population as a whole, there was no relationship between change in AUC Glucose(0-120) and changes in weight (r = -0.06, p = 0.9) or waist circumference (r = 0.01, p = 1.0). There was a tendency for a larger decrease of AUC Insulin(0-120) in the Palaeolithic group, but because of the strong association between change in AUC Insulin(0-120) and change in waist circumference (r = 0.64, p = 0.0003), this did not remain after multivariate analysis. CONCLUSIONS/INTERPRETATION: A Palaeolithic diet may improve glucose tolerance independently of decreased waist circumference.

 

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

Jönsson T, Ahrén B, Pacini G, Sundler F, Wierup N, Steen S, Sjöberg T, Ugander M, Frostegård J, Göransson L, Lindeberg S. Department of Clinical Sciences, Lund University, Box 117, 221 00 Lund, Sweden.

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. CONCLUSION: 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.