Dr. Oz Promotes Green Coffee Extract for Weight Loss
The next big thing in weight loss may be your favorite morning beverage in a pill. Recently, raw or “green” coffee extract was featured on the Dr. Oz Show, and is now a highly sought after dietary supplement. From the Ethiopian word “kaffa”, the word coffee literally means “plant of God”, and it’s no wonder… coffee is the single most important tropical commodity traded worldwide. It is also creating quite a buzz in the natural products industry.
The antioxidant thought to be responsible for green coffee’s health benefits is chlorogenic acid (CGA). Coffee beans have the highest known CGA concentration of all food plants. The CGA content of coffee is estimated to be between 5-12 g/100g. CGA is the chemical compound responsible for the flavor and color of coffee beans, as it contributes to its acidity, astringency and bitterness. Longer roasting periods and higher temperatures destroy CGA, and the best quality coffees have very little CGA. Lower grades contain higher amounts. Likewise, light roasts have more CGA than dark roasts—about 8X more. The amount of CGA in coffee is also determined by the species and variety of the coffee, whereas C. robusta has more than the more common C. arabica. Raw or green (unprocessed) coffee has the most CGA of all. Health benefits of green coffee extract supported by human clinical trials include: blood pressure lowering effects, modulation of glucose metabolism, and inhibition of fat accumulation/ weight gain.
The most recent human study on CGA-rich green coffee extract and weight loss was published last year in the journal Diabetes, Metabolic Syndrome & Obesity: Targets and Therapy. This was a Double-blind, Placebo-Controlled Crossover Trial of 22 weeks duration, 16 overweight adults, 8 men, 8 women, ages 22-46 years old. The participants were overweight, but otherwise healthy—none of them had diabetes or an underactive thyroid condition. The study compared two doses against placebo: 700mg green coffee extract per day and 1,050 mg green coffee extract per day, for a total of 350-525 mg CGA daily. All of the participants in this study lost weight, experienced reduced body fat and lowered BMI. There were no side effects. The amount of weight lost ranged from ½-1 lb per week—a loss equivalent to 10% of initial body weight on average, with no significant changes in diet or exercise. The green coffee extract used in this study is the Registered Trademark ingredient, GCA (green coffee antioxidant); manufactured by Applied Food Sciences, Inc. GCA is standardized to 45.9% CGA.
Another commercial green coffee extract, Svetol, has also been studied in human clinical trials. Svetol is a decaffeinated green coffee extract made from the CGA-rich robusta variety of coffee. It is standardized to 45% CGA. The recommended daily dose of Svetol green coffee extract (400 mg) contains the amount of CGA present in 3-6 cups of coffee, depending on the coffee variety and roasting method used. Studies on Svetol were less impressive than that which used GCA—participants only lost 5.7% of their initial weight after 8 weeks of supplementation.
These results are impressive, although the sample size in both studies was very small. A meta-analysis of the randomized clinical trials on green coffee extract for weight loss was published in 2011. This review included the older studies on Svetol and concluded that the trials were “promising, but of poor methodological quality”. Since CGA is an antioxidant with other potential health benefits such as: glucose regulation and blood pressure control, both GCA and Svetol forms of green coffee extract are certainly not harmful and may even be very helpful. I am hopeful about green coffee extract and can fully support its use. I am looking forward to larger clinical trials, which I predict will yield even more positive results.
Green Coffee Extract or Sunflower Seeds?
Just for fun, I wondered what other foods might contain high levels of CGA and possibly benefit weight loss? My research found that second to coffee, sunflower seed kernals are the highest food source, with an average of 2.8% CGA. So just how many sunflower seeds would you need to eat per day to equal the amount of CGA in the green coffee extract used in the most recent clinical trial? The answer is a surprising .6 oz or 1/8 cup per day—about 100 calories worth. Sunflower seeds also provide significant amounts of other important nutrients, such as: potassium, magnesium, iron, calcium and several B vitamins. Try adding sunflower seeds to your daily diet and see if this natural food helps you burn fat and lose weight.