Raw and unroasted coffee beans are known as green coffee beans. They exhibit strong antioxidant and chlorogenic properties like green tea. So, they promote weight loss. Both mature and immature beans are used to make an extract (weight loss supplement), because maturation does not change the amount of caffeine in the beans. In 2012, Dr. Oz introduced Green Coffee Bean Extract, and claimed that it could help burn fat and one may use it to lose weight. The show has its own medical team, which conducted a study of 100 overweight women between the ages of 35 and 49. They were given the extract or a placebo (400 mg capsules thrice a day) half an hour before each meal. It was noticed that the women who consumed the extract lost two pounds (on average) within two weeks. Women who consumed the placebo also lost an average of one pound. The reason behind this can be increased consciousness about diet over those two weeks. This itself throws light on the fact that if you are aware of what you eat, if you choose your food consciously, if you follow a balanced diet, and perform exercises regularly, then you can definitely lose weight. We all know that there doesn't exist any quick and easy solution for weight loss. But as the show has a great influence on his viewers, the product was a hit, both among men and women. Manufacturers claim that the extract offers a number of health benefits. ✦ As the beans contain a high amount of the chemical compound 'chlorogenic acid', they promote weight loss. But how much weight one would lose would highly depend upon his/her rate of metabolism, and how the body handles blood sugar. ✦ Some animal studies and a couple of human studies that have been done so far are not sufficient to prove the health benefits of the supplement. There is no sufficient evidence with the help of which we can conclude that the extract promotes weight loss. ✦ Some study results show that specific extracts like Svetol and Naturex, when taken in correct amounts, can lower the blood pressure of a person. But one should consult a physician for proper dose and the period of time for which the supplement can be taken. ✦ According to some researchers, 200 mg capsules (not 400 mg) thrice a day can help lose weight. But sometimes, a dose of 700 mg is also recommended. It is obvious that higher the dose, more would be the adverse effects. ✦ No studies have been conducted to know the long-term safety of this supplement. Whether it is safe for people who have heart diseases or how it interacts with prescribed medication, is unknown. ✦ They claim that antioxidants present in coffee beans help prevent life-threatening diseases. But you can always incorporate antioxidant-rich fruits and vegetables in your diet, and reap their benefits. It would be a more natural, healthier, and safer way of improving health. ✦ Women should avoid green coffee beans during pregnancy and breastfeeding, as researchers have not conducted enough studies and no reliable information is available about their safety during these stages of life. ✦ Various companies have started producing the extract now. For a buyer, it is difficult to decide which product is really pure and effective. According to Dr. Oz, the product should contain chlorogenic acid extract, often referred to as GCA (green coffee antioxidant) or svetol. Capsules with less than 45% GCA cannot help lose weight. ✦ Artificial ingredients and fillers can seriously affect the effectiveness of the capsules. Even if a supplement meets all these criteria, excessive consumption of the extract can lead to certain side effects, as the beans contain caffeine. ✦ Those who are allergic to coffee or caffeine should stay away from this supplement, as it can lead to an allergic reaction (rash, itching sensation, swelling in the throat, etc.). ✦ Excessive caffeine consumption can worsen diarrhea. ✦ People with high blood pressure may experience an increase in blood pressure levels after consumption of raw coffee beans. It is possible that the caffeine present in regular coffee may not affect their blood pressure. ✦ Excessive intake of caffeine through this extract can worsen irritable bowel syndrome. ✦ Caffeine can increase the pressure inside the eyes. ✦ It can aggravate bleeding disorders and can make one bleed more. ✦ Those suffering from anxiety disorders should stay away from it, as it can make the condition worse. ✦ Some studies show that the caffeine in green coffee can change the way diabetics process sugar. It can raise or lower blood sugar levels. ✦ Postmenopausal women and those diagnosed with osteoporosis should consume limited amount of caffeine, as it can compel the body to flush out more calcium through the urine. This can result in weak teeth and bones. ✦ Excessive intake of green coffee over a short period of time can increase the levels of homocysteine, an amino acid in the body. This can increase the risk of heart disease. ✦ Diterpenes present in raw coffee beans can increase blood cholesterol levels. This can eventually increase the risk of heart disease. ✦ It has been found that certain elements present in unfiltered coffee raise blood cholesterol levels. These elements are also present in green coffee. More studies are required to know whether these elements are harmful for health, or not. ✦ Certain fillers added to the capsules can cause stomach cramps. ✦ Excessive intake of caffeine can cause insomnia, nervousness, restlessness, upset stomach, increased heart rate, etc. It has been observed that people do not follow the instructions printed on the supplement jars, especially those regarding the dosage. Even if you buy a reputed brand, caffeine in the product can cause one or more side effects. There are thousands of supplements in the market, and each has its own benefits and side effects. Even if a supplement works great for weight loss, it's not worth trying if it is going to cause several undesirable side effects. It is better to lose weight with the help of exercise and a balanced diet. Disclaimer: This Buzzle article is for informative purposes only, and should not be replaced for the advice of a medical professional.