# The Effects of Raspberry Consumption on Glycemic Control and Inflammation Markers in Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

## TL;DR

This study finds that eating raspberries can increase insulin levels and reduce a specific inflammation marker, but has no significant effect on other blood sugar or inflammation indicators.

## Contribution

The study provides a meta-analysis of raspberry consumption's impact on glycemic control and inflammation markers in adults.

## Key findings

- Raspberry consumption significantly increased insulin concentrations (WMD: 1.89 μU/mL; P < 0.001).
- Raspberry consumption significantly decreased TNF-α concentrations (WMD: −3.07 pg/mL; P = 0.004).
- No significant effects were observed on fasting blood glucose, HbA1c, or other inflammation markers like CRP and IL-6.

## Abstract

Despite observing the health benefits of raspberry consumption in some recent studies, there is still no consensus regarding this effectiveness on inflammatory markers and glycemic control. This study aimed to investigate this effectiveness by performing a meta-analysis. The PubMed, Web of Science, and Scopus databases were comprehensively searched until December 2023 to find relevant randomized controlled trials. Eligible studies were screened, and relevant information was extracted. The overall effect size of raspberry consumption on each of the outcomes was estimated by following the random-effects model in the form of a 95% confidence interval (CI) and a weighted mean difference (WMD). Raspberry consumption led to a significant increase in insulin concentrations (WMD: 1.89 μU/mL; 95%CI: 1.45, 2.34; P < 0.001) and a significant decrease in tumor necrosis factor-α (TNF-α) concentrations (WMD: −3.07 pg/mL; 95%CI: −5.17, −0.97; P = 0.004), compared with the control groups. Raspberry consumption did not have a significant effect on fasting blood glucose, insulin, hemoglobin A1C, glucose tolerance tests, homeostatic model assessment for insulin resistance, C-reactive protein, and interleukin-6 concentrations. This review revealed that raspberry consumption led to a significant increase and decrease in insulin and TNF-α concentrations, respectively. However, to draw a more accurate conclusion, it is necessary to conduct studies with a larger sample size in the future.

The current study's protocol has been registered in the PROSPERO system as CRD42023477559.