Probiotic fruit beverages with different polyphenol profiles attenuated early insulin response

Jie Xu,Yvonne Granfeldt,Irini Lazou Ahrén,Martin Antonsson,Tommy Jönsson,Peter Spégel,Åsa Håkansson,Charlotta Turner,Merichel Plaza

doi:10.1186/s12937-018-0335-0

Abstract

BackgroundConsumption of polyphenol-rich fruits and vegetables may improve postprandial glucose and insulin levels and hence promote well-being. Previously it has been observed that consumption of bilberry decreases the postprandial insulin demand. The intention with the present study was to compare the impact of different supplements with various polyphenol profiles, on the postprandial glucose and insulin responses in healthy young adults.MethodsIn a randomized, controlled, crossover study the postprandial glycemic and insulin responses were observed in eleven healthy adults after intake of five different beverages containing bilberry (European blueberry), blackcurrant, beetroot, mango and rose hip, respectively; all drinks were enriched with the same composition of fermented oatmeal and probiotics. The control was a glucose drink. The profile and content of the polyphenols in the different beverages were determined by HPLC-DAD analysis. The antioxidative capacity of the different beverages were measured by TEAC and DPPH assays.ResultsBeverages containing bilberry, blackcurrant, mango or rose hip significantly attenuated the early postprandial insulin response (0–90 min), but showed no effect on glucose response. Drinks with bilberry or rose hip reduced the insulin response from the very early phase (0–30 min), and had significantly lower insulin index compared with the control. The efficiency of the bilberry and rose hip to decrease early postprandial insulin responses correlated with higher phenolic contents.ConclusionsSupplements with bilberry, blackcurrant, mango or rose hip in the tested probiotic and oatmeal enriched beverage attenuated early-phase insulin response, but had no effect on the postprandial glycemic response. The improved ability of bilberry and rose hip to lower the very early phase of insulin response seems to be due to a higher phenolic content.Trial registrationThe study was retrospectively registered at ClinicalTrials.gov with number NCT03159065.

Highlights

Consumption of polyphenol-rich fruits and vegetables may improve postprandial glucose and insulin levels and promote well-being
No significant differences regarding the incremental blood glucose concentrations were found between the groups at any of the time points, and the same was true for the glycemic responses measured by incremental areas under the curves (IAUCs) (Table 1)
Pairwise comparisons showed that Bilberry and Rose hip groups had significantly lower increase in serum insulin levels compared with the Beetroot group (P = 0.02 and P = 0.02, respectively)

Summary

Introduction

Consumption of polyphenol-rich fruits and vegetables may improve postprandial glucose and insulin levels and promote well-being. The intention with the present study was to compare the impact of different supplements with various polyphenol profiles, on the postprandial glucose and insulin responses in healthy young adults. Decreased postprandial blood glucose and insulin responses have been reported in healthy adults after consumption of freezedried fruits (apple peel, blackberry, blackcurrant and strawberry) with green tea [8], beetroot juice [9], and blackcurrants and lingonberries [10]. An attenuated postprandial insulin response, but not glucose response was reported in some studies with extract of baobab fruit [11] and berries [12]. In another study performed by the same group, no correlation could be found between the insulin lowering effect and the polyphenol composition of the berries [12]

Methods

Results

Discussion

Conclusion