Green coffee beans are raw, unroasted coffee beans. The beans contain many bioactive compounds, including chlorogenic acid and caffeine. Chlorogenic acid is the main component of green coffee beans, and most of it is removed when the beans are roasted. It is said to be responsible for green coffee's weight loss effects.
In a study published in the Journal of Medicinal Food, researchers looked at how much chlorogenic acid and caffeine there are in green coffee bean products. Researchers from the University of Scranton and Marywood University developed high-pressure liquid chromatography (HPLC) to provide a simple, inexpensive method of analyzing 54 commercially available extracts of green coffee beans.
The researchers measured both chlorogenic acid and caffeine using 5-chloroquinic acid as the standard and published extinction coefficients for the other monomeric and dimeric chlorogenic acids present. The average labeled dose of chlorogenic acid was 233?milligrams (mg), whereas the average calculated by HPLC analysis was only 157?mg. This suggested that the consumer is likely to get a little more than half of the reported label amount of chlorogenic acid in green coffee products.
The researchers also found that green coffee products contain zero to 17 percent of caffeine. Based on marketing literature, 50 percent chlorogenic acid content is the gold standard of green coffee bean products. However, based on this value, only 28 percent of the commercial products studied met this goal.
The researchers explained that consumer complaints about the lack of efficacy of green coffee extracts may simply be due to the low and variable dose of chlorogenic acid found in the product they used. Extraction solvents, time and temperature, and storage may all play a role in the high variability in chlorogenic acid content among the formulations evaluated in this study.
From these findings, the researchers suggested that stricter regulation of the process to prepare green coffee products must be implemented to prevent this large variability in commercial supplements.
While most commonly known for its weight loss effects, chlorogenic acid offers other health benefits.
Chlorogenic acid, as an antioxidant, not only fights free radicals that damage cells, but also helps regulate blood sugar. In a 2010 animal study, researchers found that the consumption of five milligrams per kilogram (mg/kg) body weight of chlorogenic acid normalized the glucose levels of diabetic rats.
In humans, consuming three to four cups of decaffeinated coffee containing high levels of chlorogenic acid lowered the risk for Type 2 diabetes by 30 percent, according to a study published in JAMA Network.
Chlorogenic acid and other antioxidants in green coffee extracts may prevent or reduce some of the cognitive and neuropsychiatric symptoms of Alzheimer’s disease, and improve brain function and mood. An animal study in the journal Nutritional Neuroscience reported that the antioxidant properties of green coffee extract helped maintain normal brain metabolism in mice compared to those that did not receive the extract. A decline in brain metabolism is an important risk factor for Alzheimer’s disease.
While more studies are needed, existing evidence suggests that chlorogenic acid may help protect against heart disease. A study published in BioMed Research International showed that it can reduce blood pressure – a key risk factor for heart disease.
The many health benefits of green coffee make it a great addition to your diet. You can find green coffee products in many natural food stores and some grocery stores. Green coffee supplements are sold in tinctures, tablet, or gel cap formulations.