Effect of 8 weeks' supplementation grape seed extract on insulin resistance in iranian adolescents with metabolic syndrome: A randomized controlled trial.

2021-01
Diabetes & metabolic syndrome 15(1)
- Alizadeh Mohammad
- Taghizadeh Shahnaz
- Kheirouri Sorayya

PubMed: 33385766
DOI: 10.1016/j.dsx.2020.12.028

Study Design

Type: Randomized Controlled Trial (RCT)
Sample size: n = 24
Population: adolescents with metabolic syndrome (MetS)
Methods: Participants were divided into grape seed extract (GSE) and placebo groups (n = 24 each) and received 100 mg/day of GSE or placebo and were placed on a weight loss diet for 8 weeks
Blinding: Double-blind
Duration: 8 weeks
Funding: Unclear

Background and aims

Insulin resistance in adolescents is a major health concern. The aim of this study was to evaluate the effect of grape seed extract on insulin resistance in adolescents with metabolic syndrome (MetS).

Methods

Participants were divided into grape seed extract (GSE) and placebo groups (n = 24 each) and received 100 mg/day of GSE or placebo and were placed on a weight loss diet for 8 weeks. Anthropometric and biochemical indices, blood pressure, dietary intake, and physical activity were measured before and after the intervention.

Results

Forty-two participants completed the trial. After the intervention, the age, sex, baseline values, energy intake and physical activity as a covariate adjusted using ANCOVA for determine differences between groups. The MD (mean difference ±SEM) of HOMA-IR between the GSE group (-1.46 ± 0.45) and the placebo group (-0.48 ± 0.47), (p = 0.020), and the MD of insulin between the GSE group (-7.05 ± 2.11) and the placebo group (-1.71 ± 2.12), (p = 0.024), were significant. Although changes were observed in other variables, they were not statistically significant.

Conclusions

GSE improves insulin concentration and insulin resistance in adolescents with MetS and provides a basis for possible application of the GSE in the clinical management of MetS in adolescents. This study registered under Randomized Clinical Trials.gov Identifier no. IRCT2013112611288N7.

Research Insights

Red Grape→Improved Blood Lipid Profile
Although changes were observed in other variables, they were not statistically significant
Effect
Neutral
Effect size
Small
Dose
100 mg/day
Red Grape→Improved Insulin Levels
The MD of insulin between the GSE group (-7.05 ± 2.11) and the placebo group (-1.71 ± 2.12), (p = 0.024), were significant.
Effect
Beneficial
Effect size
Large
Dose
100 mg/day
Red Grape→Improved Insulin Sensitivity
The MD (mean difference ±SEM) of HOMA-IR between the GSE group (-1.46 ± 0.45) and the placebo group (-0.48 ± 0.47), (p = 0.020)...
Effect
Beneficial
Effect size
Large
Dose
100 mg/day
Red Grape→Reduced Blood Pressure
Although changes were observed in other variables, they were not statistically significant
Effect
Neutral
Effect size
Small
Dose
100 mg/day
Red Grape→Reduced Body Weight
Although changes were observed in other variables, they were not statistically significant
Effect
Neutral
Effect size
Small
Dose
100 mg/day
Red Grape→Reduced Fasting Blood Glucose Levels
Although changes were observed in other variables, they were not statistically significant
Effect
Neutral
Effect size
Small
Dose
100 mg/day
Red Grape→Reduced Waist Circumference
Although changes were observed in other variables, they were not statistically significant
Effect
Neutral
Effect size
Small
Dose
100 mg/day