Green Coffee Bean Extract - Weight Loss and Side Effects
A recent study conducted by the University of Scranton on 16 overweight young adults and presented at the American Chemical Society national meeting on March 27, 2012, has demonstrated that, despite maintaining similar caloric intake levels, test subjects who consumed an extract made from green (unroasted) coffee beans lost considerably more weight than control subjects. Test subjects lost an average of 17.5 lbs (7.75 kg), or about 10.5% of their body weight over the course of 22 weeks. The study's findings were published in the journal Diabetes, Metabolic Syndrome, and Obesity.
Those consuming higher dosages (1050 mg of GCA, a standardized extract) of green coffee extract lost more than those consuming lower (700 mg) dosages. Scientists have not determined which component of the extract aided in dropping the excess weight, although some have speculated that polyphenols and chlorogenic acid, which green coffee beans have in abundance. However, the extract is notably bitter, and difficult to drink without substantial dilution in water.
Currently available extracts
Green coffee bean extracts are already commercially available. Most are standardized to contain a certain percentage of chlorogenic acid. Two important notes:
- Caution should be used in consuming any green coffee bean extract, since many have high levels of caffeine as well.
- Extract like this high in polyphenols should not be consumed with dairy or other high-calcium foods, since these foods can block the absorption of polyphenols by the body.
Other side effects
Extracts of green coffee beans have most of the alcohol- and water-soluble components you would find in the beans themselves, namely caffeine, chlorogenic acid, caffeic acid, and several other polyphenols, which are naturally-occurring phytochemicals, or substances found in plants.
Extracts containing caffeine have the same effects as other substances (coffee, tea, colas, energy drinks, etc.) that have caffeine. If you are sensitive to caffeine and want to limit caffeine intake, you should inquire about caffeine levels before considering consumption.
Other health effects are probably associated with the chlorogenic and caffeic acids, among other polyphenols, present in unroasted coffee. A survey of scientific studies on green coffee extract and its primary components turns up the following:
- A study published in Hypertension Research in 2004 showed that laboratory rats fed green coffee extract demonstrated enhanced circulation and blood vessel function, and significantly lower homocysteine levels (a marker for cardiovascular disease).
- A study published in Clinical and Experimental Hypertension in 2006, a low dose (140 mg) of GCA, the green coffee extract used in the weight loss study, administered to hypertensive subjects resulted in a significant reduction in both systolic and diastolic blood pressure levels, without any observed side effects.
While it's always wise to exercise caution when taking supplements for weight loss—the expected weight loss might never occur, and there might be unanticipated side effects—green coffee bean extract seems to be relatively safe when consumed in reasonable quantities, and its other benefits to cardiovascular health might make the supplement worthwhile to take just the same.
Please consult your doctor before beginning any supplement regimen. This article is provided for informational purposes only.