The Effects of Irvingia gabonensis Seed Extract Supplementation on Anthropometric and Cardiovascular Outcomes: A Systematic Review and Meta-Analysis.

2019-12-19
Journal of the American College of Nutrition 39(5)
- Jounghee Lee
- Mei Chung
- Zhuxuan Fu
- Jihee Choi
- Hae-Jeung Lee

PubMed: 31855111
DOI: 10.1080/07315724.2019.1691956

Study Design

Type: Meta-Analysis
Methods: Literature searches were conducted in 4 databases to identify randomized controlled trials (RCTs) investigating the effects of Irvingia gabonensis seed extract supplementation on anthropometric measures and cardiovascular biomarkers. Two investigators independently performed abstract screenings, full-text screenings, data extraction, and risk of bias assessments. Random effects meta-analyses were performed when 3 or more RCTs reported the same outcome.

Rigorous Journal

Background: It has been hypothesized that Irvingia gabonensis can promote weight loss by increasing fatty acid breakdown and inhibiting fatty acid synthesis.Objective: We conducted a systematic review and meta-analysis to evaluate the efficacy and safety of Irvingia gabonensis seed extract supplementation on weight-related health outcomes.Methods: Literature searches were conducted in 4 databases from January 2018 to identify randomized controlled trials (RCTs) investigating the effects of Irvingia gabonensis seed extract supplementation on anthropometric measures and cardiovascular biomarkers. Two investigators independently performed abstract screenings, full-text screenings, data extraction, and risk of bias (ROB) assessments. Random effects meta-analyses were performed when 3 or more RCTs reported the same outcome.Results: Five RCTs met the eligibility criteria for this systematic review. Four of the 5 RCTs were rated as having a high ROB, and only one RCT was rated as having a low ROB. Random-effects meta-analysis of the 5 RCTs showed that a significant decrease in body weight, body fat, and waist circumference was observed in relation to Irvingia gabonensis seed extract supplementation. However, the only one low-ROB trial did not have significantly different outcomes. Meta-analysis also showed beneficial effects of Irvingia gabonensis seed extract supplementation on total cholesterol, LDL-cholesterol, HDL-cholesterol, and triglycerides. Only the low-ROB trial showed a trend of increasing HDL-cholesterol levels (net percent change = 11.61%; 95% confidence interval (CI: -6.12%, 29.34%) and decreasing triglyceride levels (net percent change = -29%; 95% CI: -76%, 19%). The reported adverse events were minor in these 5 RCTs.Conclusions: Overall efficacy of Irvingia gabonensis seed extract supplementation on weight loss seems positive but is limited due to poor methodological quality and the insufficient reporting of the clinical trials. Further high quality RCTs are needed to determine the effectiveness of Irvingia gabonensis seed extract supplement on the weight-related health outcomes.

Research Insights

African Mango→Increased HDL Cholesterol
Only the low-ROB trial showed a trend of increasing HDL-cholesterol levels (net percent change = 11.61%; 95% confidence interval (CI: -6.12%, 29.34%)
Effect
Neutral
Effect size
Small
African Mango→Increased High-Density Lipoprotein Cholesterol
Meta-analysis also showed beneficial effects of Irvingia gabonensis seed extract supplementation on total cholesterol, LDL-cholesterol, HDL-cholesterol, and triglycerides.
Effect
Beneficial
Effect size
Small
African Mango→Reduced Body Fat
Random-effects meta-analysis of the 5 RCTs showed that a significant decrease in body weight, body fat, and waist circumference was observed in relation to Irvingia gabonensis seed extract supplementation.
Effect
Beneficial
Effect size
Small
African Mango→Reduced Body Weight
Random-effects meta-analysis of the 5 RCTs showed that a significant decrease in body weight, body fat, and waist circumference was observed in relation to Irvingia gabonensis seed extract supplementation.
Effect
Beneficial
Effect size
Small
African Mango→Reduced LDL Cholesterol
Meta-analysis also showed beneficial effects of Irvingia gabonensis seed extract supplementation on total cholesterol, LDL-cholesterol, HDL-cholesterol, and triglycerides.
Effect
Beneficial
Effect size
Small
African Mango→Reduced Total Cholesterol
Meta-analysis also showed beneficial effects of Irvingia gabonensis seed extract supplementation on total cholesterol, LDL-cholesterol, HDL-cholesterol, and triglycerides.
Effect
Beneficial
Effect size
Small
African Mango→Reduced Triglyceride Levels
decreasing triglyceride levels (net percent change = -29%; 95% CI: -76%, 19%).
Effect
Neutral
Effect size
Small
African Mango→Reduced Waist Circumference
Random-effects meta-analysis of the 5 RCTs showed that a significant decrease in body weight, body fat, and waist circumference was observed in relation to Irvingia gabonensis seed extract supplementation.
Effect
Beneficial
Effect size
Small

Adverse Events Reported

African Mango→Overall tolerability
The reported adverse events were minor in these 5 RCTs.
Finding
Reported