A study examined the health benefits of green coffee bean extract and its potential use in the treatment of insulin resistance and metabolic syndrome.
Metabolic syndrome, also known as Syndrome X or insulin resistance syndrome, is a cluster of risk factors that increase the chance of developing heart disease, stroke, and diabetes. More than 40% of people in their 60s or 70s are affected by metabolic syndrome.
Conditions or habits that alter the normal metabolic or biochemical functions of the body are considered risk factors for developing metabolic syndrome. These include abdominal obesity or large waistline, raised triglyceride levels, low HDL cholesterol level, high blood pressure, and high fasting blood sugar.
Current treatments for metabolic syndrome
It is important to treat metabolic syndrome to reduce the risk of heart disease and type 2 diabetes. The first line of treatment is heart-healthy lifestyle changes such as a healthy diet, weight loss, and exercise. Pharmacological treatment includes drugs that help reduce the risk of coronary heart disease and other complications associated with metabolic syndrome but so far there is no single treatment that can treat metabolic syndrome. Several side effects associated with drugs have triggered a growing interest in an alternative treatment approach for metabolic disorders such as insulin resistance and diabetes.
Green coffee bean extract and insulin resistance
Multiple studies in the recent past have shown the positive effects of green coffee bean (GCB) extract. There are two major active components in coffee beans, caffeine and chlorogenic acid (CGA), a biologically active phenol. There is a higher quantity of CGA in green bean coffee compared to roasted coffee beans.
Mounting evidence from past studies suggests that green coffee bean has anti-diabetes, anti-obesity, and anti-lipidaemic properties. Additionally, CGA has been associated with reducing the effects of insulin resistance as well as lowering blood pressure and glucose absorption.
Some studies in the past have shown a positive effect of green coffee bean extract in the treatment of metabolic syndrome, however, the results have been inconsistent.
The effects of green coffee bean extract on metabolic syndrome
A recent study published in the British Journal of Nutrition examined the effects of GCE supplementation in patients with metabolic syndrome. The researchers conducted a randomized, double-blind, placebo-controlled trial on 43 men and women from a diabetes clinic in Tehran, Iran. The participants were between 18 to 70 years of age and had a body mass index (BMI) of over 25kg/m2. They were randomly divided into the intervention group that consumed 400 mg GCE capsule (containing 186 mg of CGA) twice daily for 8 weeks or a placebo group.
The participants in both groups were instructed to follow an energy-based diet and to not change their salt intake or modify their physical activity. The researchers assessed the participants’ anthropometric indices such as weight, waist circumference, systolic and diastolic blood pressure, and BMI at the start and end of the study. Other biochemical parameters such as fasting blood glucose (FBG), total cholesterol, triglycerides, HDL cholesterol, LDL cholesterol, fasting insulin, and insulin resistance were also measured at the start and end of the study.
Green coffee bean extract reduced blood glucose and acted as an appetite suppressant
Green coffee bean extract supplements reduced systolic blood pressure, fasting blood glucose, and insulin resistance compared to the placebo group. The researchers also observed a reduction in waist circumference and appetite score of participants supplemented with green coffee bean extract.
Weight and BMI in the intervention group reduced twice as much as in the placebo group. However, the results showed no difference in the lipid profile and glycated hemoglobin levels between the intervention and the placebo groups.
The findings of this study agree with the existing evidence to suggest the beneficial effect of GCE in the treatment and management of metabolic syndrome. The dose of GCE is critical when trying to achieve the positive effects of CGA on the risk factors associated with metabolic syndrome. In this trial, participants were given 372mg of CGA/day. It is possible to consume this amount of CGA every day through coffee drinking or by taking it as a supplement.
First study to show green coffee bean extract as appetite suppressant
Resulting in the reduction in body weight, BMI, blood pressure, fasting glucose, and insulin resistance, GCE supplementation can prove to be an effective approach for the treatment of metabolic syndrome. This study is the first one to show the effect of GCE supplementation on reducing the appetite level, which further contributes to weight loss.
There are certain limitations of the study such as a short intervention period and the unavailability of professional scales and analyzers due to a budget deficit. Authors acknowledge that future studies with larger sample size and longer duration should be conducted to establish the potential health benefits of GCE for patients with metabolic syndrome.
Consistent with animal and human studies in the past, these study results reaffirm the beneficial effects of GCE supplementation in reducing systolic blood pressure, fasting blood glucose, insulin resistance, waist circumference, and appetite level. It may therefore be an effective approach in the treatment and management of patients with metabolic syndrome. Clearly, it may prove to be an inexpensive and safe means of reducing the health risks associated with metabolic syndrome.
Written by Preeti Paul, MS Biochemistry
Reference: Hanieh roshan et al., Effects of green coffee extract supplementation on anthropometric indices, glycaemic control, blood pressure, lipid profile, insulin resistance and appetite control in patients with the metabolic syndrome: a randomized clinical trial. British Journal of Nutrition (accessed January 2018)