"Green coffee" refers to the raw or unroasted seeds (beans) of Coffea fruits. Green coffee beans are cleaned, dried, roasted, ground and brewed to produce coffee. Coffee contains hundreds of components, each of which may have potential and independent pharmacological effects.
Coffee is a notable source of caffeine. However, coffee’s effects on glycemic control and weight loss have been attributed to its other components, including chlorogenic acid, quinides, lignans, and trigonelline, all of which have been shown to improve glucose metabolism in animal studies.
Chlorogenic acid has specifically been shown to inhibit an enzyme, glucose-6-phosphatase, that promotes the formation of glucose (sugar) in the liver. Hence, chlorogenic acid in coffee may be responsible, at least in part, for the reduced risk of glycemic disorders, like diabetes, with long-term coffee consumption.
It may also be the source of coffee’s anti-obesity effects. Various studies have suggested that chlorogenic acid slows absorption of fat from food intake and also activates metabolism of extra fat. Unfortunately, traditional brewed coffee doesn’t serve as a good source of chlorogenic acid. While roasting green coffee beans removes its naturally bitter taste, it also removes a significant portion of chlorogenic acid. Hence, green coffee beans remain one of the best natural sources for chlorogenic acid.
The most recent study on green coffee bean was published in January 2012 in the Diabetes, Metabolic Syndrome and Obesity journal. The researchers followed a group of 16 adults who supplemented with a special green coffee bean extract of chlorogenic acids at different dosages (either 700 or 1050 milligrams per day) for 12 weeks. All 16 adults were considered overweight, as demonstrated by a BMI of greater than 25 (a normal BMI is between 18.5 and 25).
The extract the researchers used contained an ingredient called GCA, which contains a standard green coffee extract of total chlorogenic acids and other hydroxycinnamic acids that have been known to have antioxidant health benefits. The subjects lost an average of almost 18 pounds – this was 10% of their overall body weight and 4.4% of their overall body fat.
With this promising study, many companies and websites have prized this supplement – even marketing similar fat-burning substances of their own. However, the consumer should always beware when buying unregulated supplements online. When purchasing supplements, make sure you look at the list of ingredients. When looking for a green coffee bean supplement, it should contain the chlorogenic acid extract, which can be listed as any of the following:
- GCA® (green coffee antioxidant)
Also, look for a capsule that contains at least 45% chlorogenic acid. More than 45% is okay, but pills with less than this amount have not been tested in studies that demonstrate weight loss. If you are going to take green coffee bean, the recommended dosage is 400 mg, three times a day – 30 minutes before each meal. However, some clinical trials have also demonstrated success with 200 mg.
If the bottle doesn’t list ingredients, don’t buy it! On the ingredient list, you should see no fillers and no artificial ingredients. Also, don’t be fooled by the word “pure” if you see it on a label. If you see the word “pure,” and you don’t see Svetol® or GCA®, consider another choice.
So, who is the green coffee bean extract right for? Most healthy adults, over the age of 18, who want to lose weight. It shouldn’t be taken by anyone who is pregnant or breastfeeding. The supplement is new, and there is no research on its effects on children; children should not take this supplement. You also shouldn’t take this if you have an allergy to coffee or caffeine.
Most importantly, the Dr. Oz Show will not and does not promote any particular brand of green coffee bean extract. If you see any ads or receive any e-mails that claim Dr. Oz is promoting or recommending a specific brand, ignore it and let the Dr. Oz Show know about it.
Also, understand that no pill is more effective than maintaining a regular exercise regimen and a healthy diet.