A new randomized, double-blind, placebo-controlled clinical trial provides evidence that a green coffee bean extract standardized to chlorogenic acids (CGA-7) can help with weight loss in healthy overweight adults.
Key facts:
- CGA-7 supplementation for 12 weeks resulted in significant reductions in body weight, BMI, body fat percentage and fat mass compared to placebo.
- Improvements were seen in lipid profile, with decreases in triglycerides and LDL cholesterol.
- No adverse events were reported, indicating CGA-7 is safe and well-tolerated.
- The weight loss effects are likely due to CGA’s ability to influence fat metabolism and reduce body fat.
Source: SAGE Open Med. 2021
Obesity vs. Green Coffee Bean Extract
With rising rates of obesity worldwide, natural weight loss supplements like green coffee bean extract have gained interest.
Green coffee beans are unroasted coffee beans that contain high levels of chlorogenic acids (CGAs), a group of antioxidant compounds linked to weight loss and other health benefits.
A new clinical trial published in SAGE Open Med. provides robust evidence that a specific standardized green coffee bean extract can support healthy weight loss.
Here is an in-depth look at the study and its important findings.
Clinical Trial: CGA-7 for Overweight Adults
The randomized, double-blind, placebo-controlled trial was conducted in India and involved 71 overweight adult participants.
For 12 weeks, participants took either a supplement containing 500mg of CGA-7 (a standardized green coffee bean extract containing ≥50% total CGAs) or a placebo twice daily.
CGA-7 contained 7 different CGA isomers, primarily 5-caffeoylquinic acid.
Various parameters were measured at baseline and after 4, 8, and 12 weeks of supplementation, including:
- Body weight and BMI
- Body fat percentage and lean/fat mass (via DEXA scan)
- Lipid profile
- Anthropometric measures like waist circumference
- Safety parameters like liver enzymes, glucose, and hematology
No diet or exercise advice was provided so that the independent effects of CGA-7 could be evaluated.
CGA-7 Significantly Reduced Body Weight & Body Fat
The major finding was that 12 weeks of CGA-7 supplementation resulted in significant decreases in body weight and BMI compared to placebo:
- Body weight reduced by 2.63kg in the CGA-7 group versus 0.67kg in placebo
- BMI decreased by 0.93 kg/m2 with CGA-7 versus 0.25 kg/m2 with placebo
Analysis of body composition using DEXA scans further demonstrated that these reductions were due to substantial decreases in body fat:
- Body fat percentage declined by 1.38% with CGA-7 versus 0.22% with placebo
- Fat mass decreased by 1.97kg with CGA-7 versus 0.39kg with placebo
In contrast, lean body mass increased slightly but significantly with CGA-7 supplementation.
This indicates fat loss rather than muscle loss accounted for the reductions in weight and BMI.
The researchers conclude these results provide strong evidence that CGA-7 can mitigate the risk of obesity by influencing fat metabolism and utilization.
Improved Lipid Profile & Anthropometrics with CGA-7
In addition to changes in overall body composition, CGA-7 supplementation yielded modest but significant improvements in lipid profile:
- Triglycerides decreased by 8.15 mg/dL with CGA-7 versus an increase of 1.56 mg/dL with placebo
- LDL cholesterol fell by 8.52 mg/dL with CGA-7 versus 5.74 mg/dL with placebo
- HDL cholesterol rose slightly with CGA-7 and was unchanged with placebo
Total cholesterol also declined with CGA-7, although not significantly different than placebo.
Anthropometric measurements like waist circumference and waist-to-hip ratio improved more with CGA-7 compared to placebo.
This indicates preferential loss of abdominal/visceral fat.
Together, these results suggest CGA may improve cardiovascular health markers like dyslipidemia that often accompany obesity.
The lipid-lowering effects likely contribute to its anti-obesity effects.
CGA-7 Supplement: Safe & Well-Tolerated
An important objective of this trial was to evaluate safety and tolerability of the CGA-7 supplement.
No adverse events were reported by participants taking CGA-7 for 12 weeks.
There were also no significant changes seen in hematological parameters, liver enzymes, glucose, or other blood chemistry values.
This confirms CGA-7 supplementation at 500mg daily is safe for healthy overweight adults over a 12-week period.
How May CGA Influence Weight Loss? (Mechanisms)
While this study primarily examined the efficacy of CGA-7 supplementation for weight loss, earlier preclinical studies have looked at the potential mechanisms.
Research in animal models suggests CGAs may influence weight and body composition through several pathways, including:
- Increasing fat breakdown (lipolysis)
- Reducing fat production and differentiation
- Activating AMPK, an enzyme involved in fat metabolism
- Improving insulin sensitivity and glucose metabolism
- Suppressing appetite signals like ghrelin
The antioxidant and anti-inflammatory properties of CGAs may also play a role. Additional clinical studies are needed to confirm the mechanisms in humans.
Putting Findings in Context of Other Green Coffee Research
This adds to a growing body of research demonstrating beneficial effects of green coffee bean extracts on weight management.
Several other clinical trials using varying CGA dosages, compositions, and durations have shown statistically significant reductions in body weight and fat loss ranging from 2-10% when compared to placebo.
However, this study is unique in its use of the specific CGA-7 extract, standardized to 7 CGA isomers.
It also employed precise body composition analysis using DEXA scans.
Compared to previous studies, it involved a larger number of subjects followed for a 12-week duration.
The randomized, double-blind design makes the findings more reliable as well.
Research Limitations & Next Steps
While results are promising, there are some limitations that point to areas for future research:
- Relatively small sample size of 71 participants
- Limited ethnic diversity, with mostly Indian subjects
- Short 12-week study duration
- No assessments of appetite/hunger mechanisms
- No measurements of glucose metabolism or inflammation
Longer and larger studies in diverse populations would build on these findings.
Investigating optimal dosages for weight loss would also be beneficial.
Measuring appetite regulation hormones like leptin and ghrelin could provide insight into mechanisms.
Evaluating effects on glucose control, insulin sensitivity, and inflammation would give a broader picture of health impacts.
Finally, combining CGA supplementation with lifestyle interventions like diet and exercise plans may improve results further.
Key Takeaway: Green Coffee Extract a Promising Weight Loss Tool
In summary, this well-designed clinical trial provides robust evidence that supplementing with a specific green coffee bean extract standardized to CGAs (CGA-7) can:
- Significantly reduce body weight, BMI, and body fat compared to placebo
- Improve lipid profile by lowering triglycerides and LDL cholesterol
- Be safely consumed by healthy overweight adults at 500mg daily for 12 weeks
The weight loss effects are likely mediated through CGA’s beneficial influence on fat metabolism and body composition.
Given the rising rates of obesity and related health risks worldwide, green coffee bean extract appears to be a promising natural tool to support healthy weight management.
References
- Study: Supplementation of green coffee bean extract in healthy overweight subjects increases lean mass/fat ratio: A randomized, double-blind clinical study
- Authors: HV Sudeep & K Shyam Prasad (2021)
