Plant-rich mixed meals based on Palaeolithic diet principles have a dramatic impact on incretin, peptide YY and satiety response, but show little effect on glucose and insulin homeostasis: an acute-effects randomised study.

H Frances J Bligh,Katrina Macaulay,Ian F Godsland,Theo P J Mulder,Gary Frost,Peter Murray,Karl J Hunter,John Casey,Della Hyliands,Mark J Berry,Duncan C S Talbot

doi:10.1017/s0007114514004012

H Frances J Bligh, Katrina Macaulay + Show 9 more

Open Access

https://doi.org/10.1017/s0007114514004012

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Abstract

There is evidence for health benefits from 'Palaeolithic' diets; however, there are a few data on the acute effects of rationally designed Palaeolithic-type meals. In the present study, we used Palaeolithic diet principles to construct meals comprising readily available ingredients: fish and a variety of plants, selected to be rich in fibre and phyto-nutrients. We investigated the acute effects of two Palaeolithic-type meals (PAL 1 and PAL 2) and a reference meal based on WHO guidelines (REF), on blood glucose control, gut hormone responses and appetite regulation. Using a randomised cross-over trial design, healthy subjects were given three meals on separate occasions. PAL2 and REF were matched for energy, protein, fat and carbohydrates; PAL1 contained more protein and energy. Plasma glucose, insulin, glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic peptide (GIP) and peptide YY (PYY) concentrations were measured over a period of 180min. Satiation was assessed using electronic visual analogue scale (EVAS) scores. GLP-1 and PYY concentrations were significantly increased across 180min for both PAL1 (P=0·001 and P<0·001) and PAL2 (P=0·011 and P=0·003) compared with the REF. Concomitant EVAS scores showed increased satiety. By contrast, GIP concentration was significantly suppressed. Positive incremental AUC over 120min for glucose and insulin did not differ between the meals. Consumption of meals based on Palaeolithic diet principles resulted in significant increases in incretin and anorectic gut hormones and increased perceived satiety. Surprisingly, this was independent of the energy or protein content of the meal and therefore suggests potential benefits for reduced risk of obesity.

Highlights

There is evidence for health benefits from ‘Palaeolithic’ diets; there are a few data on the acute effects of rationally designed Palaeolithic-type meals
It would be expected that such a diet, while involving cooking, would have less in the way of processing than is found in modern foods. This is based, in part, on the theory that, as farming only resulted in the consumption of dairy and cereal products in the past 7000– 10 000 years, Abbreviations: þ iAUC, positive incremental AUC; EVAS, electronic visual analogue scale; Gb, glucose basal; GIP, glucose-dependent insulinotropic peptide; GLP-1, glucagon-like peptide-1; Ib, insulin basal; PAL1, Palaeolithic meal 1; PAL2, Palaeolithic meal 2; PYY, peptide YY; reference meal based on WHO guidelines (REF), reference meal; T2D, type 2 diabetes
Many Palaeolithic diets propose a high level of animal protein, and to separate the possible effects of this from the fruit and vegetable component, PAL2 was designed to have a lower level of protein that matched that of the REF, while PAL1 was designed to have the higher level of protein used by other authors, but with the same level of carbohydrate

Summary

Introduction

There is evidence for health benefits from ‘Palaeolithic’ diets; there are a few data on the acute effects of rationally designed Palaeolithic-type meals. It would be expected that such a diet, while involving cooking, would have less in the way of processing than is found in modern foods This is based, in part, on the theory that, as farming only resulted in the consumption of dairy and cereal products (that were themselves dependent on more intensive processing) in the past 7000– 10 000 years, Abbreviations: þ iAUC, positive incremental AUC; EVAS, electronic visual analogue scale; Gb, glucose basal; GIP, glucose-dependent insulinotropic peptide; GLP-1, glucagon-like peptide-1; Ib, insulin basal; PAL1, Palaeolithic meal 1; PAL2, Palaeolithic meal 2; PYY, peptide YY; REF, reference meal; T2D, type 2 diabetes. We decided to develop Palaeolithic diet principles while using modern foods and meal design, but keeping processing to a minimum to maintain plant structures These mixed meals consisted of fruit, vegetables and protein, but lacked starchy cereals, dairy products, legumes, and refined fats and sugars. It was hypothesised that Palaeolithic meals would have a lower glucose response, and that this would be indicated by altered incretin and satiety responses

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