Green Coffee Beans For Weight Loss

Last updated October 18th 2014

Green coffee beans are one of the most popular diet pill ingredients on the market. They are featured in many different diet pills and weight loss supplements thanks to their fat burning capabilities.

Green coffee beans were first hyped up by Dr Oz on his self-titled show in 2012. Since then, they have remained one of the most popular diet pill ingredients available today. After they were first mentioned on Dr Oz’s show, green coffee bean products quickly began flying off the shelves. That goes some way to show how much influence Dr Oz when it comes to selecting diet pills, but do green coffee beans live up to the hype? Have the many people who have bought it found that it works? This article will look at green coffee beans in detail to see if they really do live up to the hype.

What Are Green Coffee Beans?

Green coffee beans are simply unroasted coffee beans. Whenever coffee beans are roasted, the amount of chlorogenic acid in them is greatly reduced. Green coffee beans therefore have a much greater amount of chlorogenic acid in them than standard coffee beans that have been roasted. Chlorogenic acid is widely believed to have numerous health benefits, particularly for high blood pressure and weight loss. For high blood pressure it is thought that green coffee, and therefore chlorogenic acid, can affect blood vessels, thereby gradually reducing blood pressure. For weight loss, it is thought to directly influence the way in which the body handles both metabolism and blood sugar; it reduces the rate at which glucose is absorbed into the bloodstream and increases metabolism, along with thermogenesis. It is able to increase the rate of these two processes by releasing catecholamines, which can make the body feel more motivated, active and alert. As you would expect, green coffee beans also contain caffeine, which is their other key ingredient. Caffeine contains antioxidants, which can help prevent a number of different diseases and conditions if taken in high quantities; they can also help prevent free radicals from damaging the body.

 What Does Dr Oz Say About Green Coffee Beans?

Dr Oz first mentioned green coffee beans on his self-titled show in 2012. It was claimed on the show that green coffee beans can burn fat fast and that diet and exercise are not required while taking green coffee beans. In a Youtube video, Dr Oz can be seen mentioning a study that his TV show’s medical department conducted on green coffee beans. For this study, a group of 100 overweight women with BMIs between 25 and 45 were recruited. None of the women were pregnant or breastfeeding, nor did any of them have any major medical issues. Each woman was instructed to take a 400mg tablet half an hour before each of the three main meals and was told not to change their diet; some took green coffee beans, while others took a placebo. The women who had taken green coffee beans lost on average 2lbs, while the placebo group lost on average 1lb. Dr Oz himself claimed the result of the placebo group was because the women were more aware of the diet because they were asked to keep a diet diary as part of the study. This study was carried out by Dr Oz in response to an earlier episode on green coffee beans which drew criticism because the study mentioned in the show was not the ‘staggering’ proof that Dr Oz; it showed results, but it was far from a high-quality scientific study. Nonetheless, sales of green coffee bean soared after both episodes about it.

What Claims Do Green Coffee Beans Make In Regards To Weight Loss?

The key ingredient in green coffee beans that is responsible for weight loss is chlorogenic acid. The main way in which chlorogenic acid targets weight loss is by blocking carbohydrates. Taking a diet pill that blocks carbohydrates has almost the same effect as just consuming fewer carbohydrates. Diet pills that block carbohydrates can be very effective for weight loss, with some claimed to block as much as 80% of carbohydrates.

The caffeine in green coffee beans helps target two areas of weight loss: fat burning and metabolism boosting. Caffeine sends signals to the fat cells instructing them to break down; it does this by stimulating the nervous system. It also causes fat cells to break down by increasing the amount of epinephrine, also known as adrenaline, in the bloodstream. Epinephrine travels along the bloodstream to the fat tissues and sends them signals ordering them to break down. As regards metabolism boosting, caffeine has known metabolism boosting effects and can increase the user’s resting metabolic rate by as much as 11%. The greater the metabolic rate is, the easier losing weight becomes.

As well as this, caffeine gives the body an energy boost and makes the user feel more alert; these can both result in the user being more motivated to exercise. However, main problem with caffeine is that the body can become tolerant to its effects quite quickly, so it is only really effective for short-term weight loss. It can also become quite addictive, which results in the user being more likely to become tolerant to its effects. If you could consume green coffee beans for a few weeks, then go a few weeks without it, then repeat the cycle, you might be able to keep resetting your body’s tolerance to caffeine, thereby experiencing the effects every time you start consuming it after a period of not consuming it.

Is There Any Evidence To Support These Claims?

As previously mentioned, Dr Oz himself has had a study on green coffee carried out, where people who took green coffee beans lost more weight than those who took a placebo. The problem with this study is that it was not carried out in line with all the proper procedures of a clinical study. This study lasted only two weeks, which is not enough time for something like a diet pill to be thoroughly tested.

There are some proper clinical studies that have been carried out on green coffee beans. This study was carried out to determine whether chlorogenic acids affect glucose uptake, insulin secretion and gastrointestinal hormone secretion in humans. For this study, nine participants, who had been fasting, consumed 25g glucose in either 400ml water (the control), 400ml decaffeinated coffee or caffeinated coffee. A number of blood samples were then taken over the following three hours. The conclusion of this study was that chlorogenic acid may have an impact on the transportation of glucose. In other words, it may prevent carbohydrates from being absorbed. Another similar study was carried out. This study showed that consuming instant coffee that had been enriched with chlorogenic acid resulted in a 6.9% reduction of the glucose absorption rate when compared to a control group.

As for green coffee beans and fat burning, this study measured sweat gland density in 10 participants after caffeine was consumed. The conclusion of this study was that the group who had taken caffeine had higher levels of activated sweat glands compared to the group that had not taken caffeine. It was therefore concluded that caffeine increases activated sweat gland density and does so by stimulating the sympathetic nervous system. This study sought to determine whether caffeine can decrease insulin sensitivity in humans. For this study hypoinsulinemic-euglycemic glucose clamps were used to determine the insulin sensitivity of the twelve participants, who had either caffeine or a placebo administered intravenously. The results of this study showed that caffeine decreased insulin sensitivity by as much as 15% and levels of plasma epinephrine increased fivefold. The conclusion was that caffeine can decrease insulin sensitivity in healthy humans possibly because of the increased plasma epinephrine levels.

With regards to metabolism boosting, this study was carried out to determine the effects of caffeine on energy expenditure and body temperature. The twelve participants, who were all males, consumed 150ml decaffeinated coffee with or without 200mg caffeine. Various measurements were taken during the three hours after consumption. The results of this study showed that consuming caffeine resulted in metabolism increasing by as much as 3-11%.

While results of the studies mentioned above do sound promising, it is worth bearing in mind that some of these studies have been quite small as they have involved a small number of people and have not lasted that long. Also, it is often the case that clinical studies are carried out by companies, or with the backing of companies, who have an interest in good results. In other words, companies are after good results to show their products work, so they sponsor clinical studies. That is not to say that clinical study results have been doctored in any way to show good results, but it is something worth bearing in mind.

Bowl Of Green Coffee Beans

How Do Green Coffee Beans Compare To Other Ingredients? 

Green coffee beans are more likely to help you lose weight than acai berries because there is at least some clinical evidence that supports green coffee beans’ weight loss properties, whereas acai berries have no clinical evidence and are more of a health food. Raspberry Ketones are claimed to tackle weight loss, but again there is a lack of clinical evidence, with no studies actually carried out on humans. Green coffee beans are most similar to Garcinia Cambogia because both have some clinical evidence behind them and both have been hyped up by Dr Oz and the media in general. If it comes down to choosing between acai berry, Raspberry Ketones, Garcinia Cambogia or green coffee beans, you will probably stand a better chance of losing weight with Garcinia Cambogia or green coffee beans.

Green Coffee Beans Vs Garcinia Cambogia

Garcinia Cambogia is a fruit resembling a green pumpkin and is native to Indonesia, though it is also found in Central Africa and Asia; it is the rind of the fruit that is used to make medicine; the key ingredient in the fruit is HCA, which is responsible for Garcinia Cambogia’s weight loss properties. It targets several areas of weight loss, can help with emotional eating and is considered to be quite safe. The areas of weight loss that it targets are carbohydrate blocking, fat burning and appetite suppression. Despite Garcinia Cambogia being a very popular diet pill ingredient, results for clinical studies on it have so far been mixed. One study shows that Garcinia Cambogia causes more weight loss than a placebo, while another study shows mixed results. For the study with positive results, the group that took Garcinia Cambogia Extract lost on average 1.3kg of weight more than the placebo group. These studies used Garcinia Cambogia with 60% HCA; it is generally accepted that any decent Garcinia Cambogia diet pill should contain at least 50% HCA in order to be reasonably effective.  Garcinia Cambogia and green coffee beans are quite similar in that they target several different areas of weight loss and have been hyped up by the media as the next wonder pill. Both do have promising weight loss properties, but what lets both ingredients down is a lack of numerous and thorough clinical studies that validate their weight loss claims.

Green Coffee Beans Vs Raspberry Ketones

Raspberry Ketones is a chemical that give raspberries their distinctive smell. Because a lot of raspberries would be needed to produce even a small amount of Raspberry Ketone, the Raspberry Ketones used in diet pills are synthetic. The main problem with this ingredient is that has a similar make-up to synephrine, which has been linked to a number of serious side-effects.

The problem with determining the effectiveness of Raspberry Ketones is that there are no reliable clinical studies on humans to go by. There is one study that was carried out on rats where Raspberry Ketones were shown to help prevent weight gain, but there is no telling whether Raspberry Ketones would have the same weight loss effects in humans. It should also be mentioned that the rats in the study did not actually lose weight, instead they just gained less weight than others. Taking that into consideration, it does not even show that Raspberry Ketones can cause weight loss in animals. Also because there are no clinical studies to go by, it is uncertain exactly what the recommended daily dose of Raspberry Ketones is. There are two things that set green coffee beans apart from Raspberry Ketones: safety and clinical studies. Green coffee beans are supposed to be quite safe and there are at least some clinical studies on them, whereas with Raspberry Ketones, there are questions about its safety and there have been no clinical studies on humans.

Green Coffee Beans Vs Acai Berries

Acai berries are said to be a ‘superfood’ because it can help with weight loss and has numerous other health benefits. These berries are dark purple in colour and are found growing in large clusters near the tops of palm trees in the Amazon rainforest. The pulp and skin of the berries contain amino acids, antioxidants and fibre, as well as several fatty acids, minerals and vitamins. One of the main reasons why the berries have become so popular is because they have a large concentration of antioxidants, which have been known to have positive effects on the health of the heart and they prevent other molecules from becoming oxidised. Acai berries are not seen as commonly in diet pills as other ingredients, such as green coffee beans and Garcinia Cambogia, because there is no clinical evidence to suggest they have anything to do with weight loss. When they are used in diet pills, it is usually because of their health benefits, not because of what they can contribute to weight loss. Some claim the berries contribute to fat burning, but again there is not enough clinical evidence to support these claims. The main difference between green coffee beans and acai berries is that green coffee beans do at least have some weight loss properties that have clinical backing.

Are There Any Other Benefits To Green Coffee Beans?


One of the reasons why green coffee beans are so popular, in addition to the exposure they have been given by Dr Oz, is because they have a number of health benefits associated with them. It is often the case that diet pills have added health benefits – even if people do not lose weight from taking the pills, they like the fact that the pills are still benefitting them in some way. Green coffee beans have been shown to reduce high blood pressure and improve glucose metabolism. It is specifically the chlorogenic acid present in green coffee beans that is responsible for these health benefits. Giving the body extra amounts of chlorogenic acid can help to reduce the amount of glucose absorbed by the body; while this can help with weight loss in general, it can also help with the management of diabetes. A study showed that chlorogenic acid can indeed reduce glucose absorption, however this study was carried out on rats, so there is no telling whether chlorogenic acid would have the same effect in humans. The chlorogenic acid in green coffee beans is also claimed to be good at reducing high blood pressure because it is thought to affect blood vessels in a positive way. A study was carried to determine the blood pressure-lowering effects of chlorogenic acid in a group of 28 participants who all had mild hypertension. The participants were given either a placebo or 140mg of chlorogenic acid daily. By the end of the study, the group who had been taking chlorogenic acid had reduced blood pressure, whilst the placebo group did not experience a reduction in blood pressure. It is thought that green coffee beans can treat or help with Alzheimer’s Disease, type 2 diabetes and infections, though there is limited clinical evidence available to support any of these claims.


What Side Effects Are Associated With Green Coffee Beans?


According to WebMD, green coffee beans are quite a safe ingredient. There have only been a few clinical studies carried out on them, and these studies have shown them to be relatively safe when taken at recommended doses, though an optimal dosage has not yet been determined by a clinical study; according to the studies, there are no major side-effects associated with green coffee beans. There is one study, however, which may indicate that there are some side-effects associated with green coffee beans. For this study a group of 18 people aged from 18 to 70 was recruited and each person was asked to take one tablet with food and a glass of water three times a day for forty days. Of the eighteen, only fifteen completed the study. The three who dropped out did so after experiencing discomfort. One had a serious headache for four days, one had gained 6lbs and reported feeling nauseous, while the third had a urinary tract infection. The participants with the headache and the urinary tract infection saw their side-effects subside once they had stopped taking the tablets. Further, larger studies are required to determine whether these side-effects were in fact caused by green coffee beans. Green coffee beans contain caffeine, so they can cause side-effects related to caffeine, such as jitteriness and rapid heartbeat.


Where Can You Buy Green Coffee Beans?

As green coffee beans are featured in many different diet pills, there are plenty of places where you can buy them. Amazon is a good choice – simply typing in ‘green coffee beans’ brings up quite a long list of various products containing the ingredient, including Green Coffee Bean Platinum and 100% Pure Green Coffee Bean Extract, to name just a few. Holland and Barrett’s online shop also sells a variety of products based on green coffee beams, including their own branded product. There are also several websites, such as York Coffee Emporium, that sell green coffee beans in their natural form and not as a diet pill ingredient.

Beware Of Green Coffee Bean Scams

Unfortunately whenever something becomes popular, there will always be those who try to make a sort of scam out of it and green coffee beans are no exception. So-called ‘free trial’ scams involve you receiving shipments of the product without you having actually ordering them. Of course, you are then charged for these extra shipments. Usually you first sign up for the free trial scheme thinking you will receive only what you have ordered. Once the trial is over, you will then be sent extra bottles, usually a month supply every month; the problem with these trials is that many websites do not advertise them, so you end up signing up to them without realising it, until money starts coming out of your account. A problem with quite a few diet pill sites is that they do not have great customer service, so it is not unheard of for people to struggle to get their money back because they cannot get through to the right people. By making these trials difficult to cancel, the companies behind them are making more money by essentially tricking you into purchasing more of their product. Some examples of free trial scams associated with green coffee products include: Pure Green Coffee, Nutra Green Coffee Cleanse and GCBX, though this list is by no means exhaustive.

What To Look For In A Green Coffee Bean Retailer

When buying any diet pill or weight loss supplement online, you should always have a look at the official website, as this is the best indicator of whether the company behind the product is reputable or not. Even if you are purchasing the product from a trusted retailer like Amazon, it is still advised that you check the official website, just to be on the safe side. When looking at any official website for a diet pill/weight loss supplement, there are several things you should look out for that will tell you the company can be trusted. Any good retailer will provide sufficient contact details on their website; this allows customers to directly get in touch with the company should they have any problems, such as late delivery, faulty products or serious side-effects. A lack of contact details shows that the company is not prepared to deal with customer concerns. A money back guarantee is another good sign that the company can be trusted. Many companies offer a guarantee for as long as 60 or 90 days, sometimes even longer. This offers you some protection as a customer and allows you the chance to get your money back should you have any problems with the product. Finally, the more information the company reveals about itself, the more you should be able to trust them. There are many diet pill sites that offer no information about the company and there are many that offer an abundance of useful information, such as the company’s history, goals, manufacturing processes, etc.



Green coffee beans are one of the most popular diet pill ingredients around today thanks to the exposure given to them by Dr Oz. It is always interesting to see whether ingredients that are hyped up live up to the hype and actually have the potential to help with weight loss. Green coffee beans certainly do appear to have some weight loss qualities as they contribute to several different areas of weight loss. The problem with green coffee beans is that there are not enough clinical studies available to attest to its weight loss claims. The clinical evidence so far is quite promising, but further and larger studies are needed before it can be said with confidence that green coffee beans can help with weight loss.