Best Appetite Suppressant Diet Pills

Last updated January 29th 2015

Battling hunger is one of the hardest parts of weight loss, thus appetite suppressing is a key area of weight loss as it helps you feel fuller for longer. But which diet pills tackle this area effectively?

Appetite suppression is one of the four key areas of weight loss. Appetite suppressants work by tricking the body into believing it is full or is just not hungry at all. Many of these products trigger an increase in the production of serotonin and catecholamine. These two chemicals are both found in the brain and are largely responsible for the regulation of mood and appetite. The more of these chemicals there is in the body, the more appetite is suppressed. Whenever appetite is suppressed, you are much less likely to feel hungry and have food cravings.

How do Appetite Suppressants work?

Appetite suppressants generally claim to work in one of two ways. By far the most common of these is by adjusting the amounts of certain neurotransmitters associated with appetite control in the brain, such as serotonin and catecholamine. Products either alter these concentrations directly, or some act to make the brain believe that they have been altered when actually the amount of neurotransmitters remains the same. Either way, these products work because the brain then signals to the body that you are not hungry, when you usually would be.

The second, less common, method of appetite suppression impacts the stomach rather than the brain. Generally speaking, these products claim to contain ingredients that expand once they reach the stomach, creating a gel-like substance when they come in to contact with water. This makes the stomach feel full, but the composition of the substance means that it is not digestible, and instead will pass through the gastro-intestinal system without being absorbed, and be excreted naturally in the stool.

Whichever form of appetite suppressing product you are looking for, they ultimately aim for the same end result – making your body feel fuller for longer, reducing the amount that you eat during meals, and reducing the amount that you snack between meals. They should result in a reduction in consumption, and thus a reduction in calorie intake. If taken alongside a healthy diet plan and regular exercise, they may be able to significantly benefit your weight loss regime.

Appetite suppression does not directly cause weight loss, but it can reduce your daily calorie intake by quite a significant amount. If taken regularly, appetite suppressants can be an effective way of achieving weight loss because they can cause you to consume much less food, which means much less fat is being consumed. It can take a good few weeks for the body, and especially the stomach, to adjust to smaller portion sizes, so weight loss will not happen overnight, but it can happen if appetite suppressants are taken regularly over a period of time.

Are Appetite Suppressants the Right Product for you?

Appetite suppressants constitute one of four main methods of weight loss. The weight loss supplement market can be broadly grouped in to those that work by suppressing the appetite, those that target fat burning and fat binding, those that block carbohydrates, and those that boost the metabolism. Which of these products you look for will be dependent on your health and lifestyle.

Products that claim to work as fat burners generally increase the speed with which fat molecules are broken down once consumed in the diet and absorbed by the body. This is usually achieved through the process of thermogenesis – increasing the internal body temperature, which improves the activity of the enzymes involved in lipolysis (the breakdown of fat). Products claiming to be fat binders work in a different way – these usually contain ingredients that are able to bind to fat molecules in the digestive system before they are absorbed by the body. By binding to the molecules, they form a complex that is too large for absorption through the small intestine membrane, and so the molecules are passed through the systems and excreted naturally in the stool.

Metabolism boosters work in a similar way to fat burners; these products generally increase the activity of cells in the body, making them work harder. The harder the cells work, the more energy (and so calories) they burn. This is also usually obtained through thermogenesis. Finally, there are carbohydrate blockers; these products work in a similar fashion to fat binders. They prevent the action of the enzymes involved in the breakdown of carbohydrates. Carbohydrates are large complexes and so generally speaking, can’t be absorbed in to the body until they have been broken down in to their individual sugar components. Blocking the enzymes that break them down thus means that many of these molecules will remain too large for absorption, and will pass through the body naturally.

Each of these product types works in a slightly different way, and it is likely that some will suit you better than others. In order to decide which will work best for you, factors such as your weight loss goal, your lifestyle, health, ability to perform exercise, and diet must be considered. Appetite suppressants are a popular choice amongst consumers, but they do have their downsides. For example, these products often have side effects, and should not be consumed by people with certain health conditions (see section below for more detail). They are also not going to help you to lose any weight immediately, and on their own.

Appetite suppressants are a relatively long term aid to obesity, so you must be patient. They should help you to gradually reduce the amount that you consume, but they will not physically help you to burn off any fat, like other products claim to. Appetite suppressants may be a good choice for people who want a gradual, but positive, trend of weight loss, and will certainly be most effective if combined with a reduced calorie diet and regular exercise, though in theory, the exercise should not be key for weight maintenance.

Fat binders and carbohydrate blockers would suit a similar lifestyle – i.e. somebody who is willing to be persistent and wait for changes to occur. Of course which of these you might opt for will depend primarily on the constituents of your diet. If you feel you consume too many carbohydrates, then carbohydrate blockers might be most effective, or if fatty foods are your downfall, then it may be best to opt for fat binders. Again, in theory, these products do not need to be consumed alongside a large amount of exercise, and may help you to lose weight gradually.

Fat burners and metabolism boosters however, might suit a different kind of person. These may be best for people who are still very active, and who do not suffer from many health conditions. These products can have side effects relating to the gastro-intestinal tract in particular, and may not be recommended for older people. Fat burners and metabolism boosters are also often the preferred choice of people who want to lose weight quickly, alongside a healthy diet and regular exercise.

Side Effects and Interactions associated with Appetite Suppressants

No weight loss supplement will be entirely free from possible side effects, and appetite suppressants are no exception. People who are under the age of 18, are pregnant, or breast feeding, should avoid weight loss supplements entirely. Due to their interaction with the brain, it is recommended that people who have a history of any form of psychological condition, such as anxiety or depression, do not consume appetite suppressants.

Appetite suppressants may cause a number of side effects, examples of these include: nervousness, restlessness, inability to sleep, irritability, dizziness, dry mouth, upset stomach, nausea, gastro-intestinal discomfort, stomach cramps, flatulence, bloating, diarrhoea, loose stools, and constipation. Possible more serious side effects include chest pain, increased heart rate, increased blood pressure, and difficulty urinating. If any of these occur, or any of the more mild side effects persist for a long period of time, then you should stop taking the product and consult a doctor immediately.

This is certainly not a comprehensive list of all side effects that may be related to appetite suppressants, and side effects and interactions will differ depending on the precise product that you are taking. Be sure to check the ingredients of the product closely before consuming it. If you have any pre-existing medical conditions, take any form of medication, or are just unsure about how a product might affect you, then you should contact a doctor before deciding on a product.

How to Identify a good Appetite Suppressing Product

If they haven’t been rigorously tested, diet pills that claim to work by suppressing the appetite can be dangerous as they usually involve altering the amount of neurotransmitters in the brain. For this reason, it is important to research each ingredient carefully, and ensure that they have undergone reliable clinical trials. It is also best to research the products as a whole before purchasing them. The best way to determine the efficacy and the safety of a product is by looking at scientific studies. You can either search for these yourself, or else a selection of clinical trials are summarised in each review article on Healthy Compare, so you can just search for the product on the website and read the reviews there.

It is also important to look at independent customer reviews on the product; these will give you some idea of what proportion of people the product works for, and whether it has any common, recurring side effects. Make sure that when looking at reviews, you read a wide variety (from people who rated the product highly and lowly). Also ensure that these reviews are independent by searching for them in a search engine – the reviews and testimonials provided on product websites are not always genuine, and will often give you a biased selection.

Once you have determined whether or not a product or ingredient is likely to work for you, you must choose carefully where to purchase it from. It is recommended that you buy health supplements from well known high street stores, rather than from independent stores on the internet, and websites such as Ebay. This guarantees you a level of safety. If you do however choose to buy from the internet, you must be sure that you are purchasing from a reliable company. In order to check this, search the website for information regarding, for example, the history of the company, the returns policy, a full list of contact details (including a postal address, telephone number, and email address), and read any terms and conditions.

It is also useful to search for independent customer reviews of both the retailer and the manufacturer of the product. These should give you some idea of the reliability of the company, and should flag up any potential scams. Unfortunately, scams are common to the weight loss supplement market, so be wary of companies that do not provide much information about the company, those that only sell one product, and those that offer a free trial – these often do not end up being free, and this will be written somewhere in the terms and conditions.

Common Ingredients in Appetite Suppressants

Caffeine: Caffeine, or caffeine anhydrous as it is usually called on the ingredients list, is a common addition to weight loss supplements for its apparent ability to suppress the appetite. There is a mass of scientific studies available studying the impact of caffeine when combined with other substances on weight loss, but none of these appear to test the ability of caffeine to work specifically as an appetite suppressant.

scientific study looked at the effect of a green tea and caffeine mixture on weight maintenance following weight loss. A total of 78 overweight and moderately obese subjects were used in the randomised, double blind, placebo controlled trial. A low calorie diet was implemented for four weeks, after which time the weight of the subjects was monitored for three months. During this maintenance period, subjects were given either a mixture of green tea and caffeine, or a placebo. The results showed that those who consumed high quantities of caffeine reduced their body weight more than those who only consumed small amounts of caffeine. These effects were attributed to the processes of thermogenesis and fat oxidation, rather than appetite suppression.

The remainder of studies on the impact of caffeine on weight loss appear to be coupled with other substances, most often ephedra, that are known to have a significant impact on weight loss. As such, the results of these studies cannot be directly associated with the impact of caffeine. It seems that there are no direct studies on the impact of caffeine on the appetite, and so it cannot be stated with certainty whether it has an impact or not. Some customer reviews of products imply that it does work for some people, but has less of an effect in others.


Green Tea (EGCG): Green tea has long been renowned for its potential use as a weight loss aid, and as with caffeine, is often added to appetite suppressing weight loss substances despite it being best known for working to increase thermogenesis and fat burning. A literature review reveals no papers that have attempted to study the impact of green tea, or EGCG, on the human appetite. As such, this cannot be discussed in detail as evidence in favour or against is lacking. Some studies on the impact of the substance on weight loss in general can however be discussed.

One trial was undertaken using 60 obese subjects and was performed to investigate the impacts of green tea on weight loss. Over 12 weeks, half of the participants were randomly allocated to the test group, who consumed green tea daily, and the other half to a placebo group, who consumed a placebo daily. The authors concluded that green tea consumption does have an impact on decreasing body weight, and it achieves this by increasing energy expenditure and fat oxidation in the body.

On the other hand, one study did not provide such positive results. The authors of this study investigated the effect of green tea extract consumption on body weight. 46 overweight female volunteers were used in the study, all of whom were fed a low energy diet supplemented with either green tea extract, or a placebo, for 83 days. The results suggested that the consumption of green tea alongside a low energy diet had no impact on body weight or body composition when compared to placebo.

Literature reviews can be extremely useful for judging the effects of a substance as they group together the majority of studies performed, and make analyses based on all of the study results. A meta-analysis of studies examining the impact of green tea on body weight has been performed, and can be found here. After a thorough literature review, eleven articles fitted the inclusion criteria and were included in the analysis. Overall, green tea catechins were found to significantly decrease body weight and aid weight maintenance following a period of weight loss. Although small, this effect was deemed to be significant.

Overall, the studies that have been performed on the impact of green tea and EGCG on weight loss have shown varied results. Several concluded that the substance has a significant effect on weight loss, increasing the rate of fat oxidation, whilst others showed no significant difference between the effect of green tea and that of placebo. It seems that the substance may thus have a small impact on some people, but will not work for everybody. There is no evidence to suggest that green tea extract works as an appetite suppressant.


Glucomannan: Glucomannan is a fibrous substance that is regularly added to appetite suppressing diet pills. The substance is derived from the root of the konjac plant and has been used in herbal medicine in the past to treat constipation, type two diabetes, and high cholesterol, as well as obesity. It is also added to foods as a thickener. There was a lot of hype over the potential of this ingredient as an appetite suppressant after it was featured on the Dr. Oz Show. Glucomannan is believed to work using the second method of appetite suppression discussed above – once it has been consumed, the fibrous substance supposedly interacts with water and expands in the stomach, making you feel full.

A small number of preliminary scientific studies have been performed on the effects of glucomannan on weight loss. One study involved just 20 subjects, all of whom were obese. Over a period of eight weeks, subjects were given either 1g of glucomannan fibre or placebo three times a day, before each meal. The results of this trial indicated that the treatment group saw a significant amount of weight loss, and a lowering of cholesterol. It must be mentioned however that although interesting to know the results, 20 subjects is not enough to make this a reliable study.

A larger study compared the impact of 3g of Plantago ovata husk and 1g glucomannan with a placebo taken three times a day for 16 weeks. 200 overweight or obese volunteers were used in this study that was performed using double blind, placebo controlled methods. After 16 weeks of treatment and a calorie restricted diet, the authors found that differences in weight loss between the two groups were not statistically significant. The only impact reported was that the group consuming the fibrous substances had lower cholesterol levels. This impact cannot however be attributed only to glucomannan.

A meta-analysis of studies performed on glucomannan summarises the results of 14 studies that fit the inclusion criteria, and statistical analyses performed on these studies showed that glucomannan seems to mostly have an impact on lowering total cholesterol, but also has a small beneficial impact on aiding weight loss and lowering triglyceride levels. The substance generally seems to be well tolerated by subjects, and no adverse effects were reported in any of the studies discussed.


African Mango (Irvingia  gabonesis): This ingredient is extracted from the fruit of a tree native to central and western Africa. The fruit of this tree is widely consumed in Africa, but it is extract of the seed that is believed to hold weight loss properties. The substance is particularly well known for its potential benefits as an appetite suppressant, and as such can be found in many appetite suppressing products. African mango has only been the subject of a few scientific studies that investigate its impact on weight loss.

clinical trial on 40 subjects was carried out in 2005 to evaluate the effectiveness of African mango seeds as weight loss aids. The trial was randomised, double blind, and was performed over a period of one month. During this time, one group of subjects were given 1.05g of African mango extract three times a day, and the other group were given a placebo. Statistical analyses suggested that the group consuming African mango lost significantly more weight than the placebo group. They also saw a significant decrease in the total cholesterol of the African mango group.

Another study produced similar results. This trial was performed on 102 overweight or obese volunteers that were randomly split either in to a group that received 150mg African mango extract two times a day before meals, or a placebo. The results showed that individuals in the group taking the African mango extract lost more body weight, body fat, plasma cholesterol, LDL cholesterol, and blood glucose than those in the placebo group.

Finally, a study was performed on the impact of Irvinia gabonensis when taken with Cissus quadrangularis in overweight and obese subjects. Randomised, double blind, placebo controlled methods were used, and 72 subjects participated in the study. Over a period of 10 weeks, individuals were allocated to one of three groups. The first group received a placebo, the second received Cissus quadrangularis only, and the third received a mixture of Cissus quadrangularis and Irvinia gabonensis twice daily before meals. Results suggested that Cissus quadrangularis alone had a significant impact on weight loss, but this impact was even larger when consumed alongside Irvinia gabonensis.

Chemical-Based Vs Herbal-Based Appetite Suppressants

Appetite suppressants fall into two categories: chemical-based pills and herbal-based pills. Chemical-based pills are mainly available in the US on prescription due to the fact that they are closely related to amphetamines and have a large number of known side-effects associated with them. They are harder to acquire than herbal-based pills and are only prescribed to those who need them the most. Over time, the body adjusts to the daily intake of these chemicals, so the efficacy of chemical-based diet pills begins to decrease after about 2 or 3 months of regular usage. Chemical-based diet pills can also become addictive, which can decrease their efficacy even further. They work in two ways: by sending signals to the brain to tell it the user is full and by stopping the brain from sending signals to other parts of the body to tell them the body is hungry. The result of these two actions is that the user will eat less at meal times and will have snacks much less often. Because the user is eating less, their weight should eventually go down.

Herbal-based appetite suppressants, on the other hand, contain natural ingredients and have far fewer side-effects associated with them. Most appetite suppressants fall into this category. Herbal-based appetite suppressants work by generating excess bulk in the stomach, which causes the user to feel full even if they have not eaten that much food. These appetite suppressants usually contain a large amount of fibre, which swells in size when it comes into contact with water. The pills are manufactured in such a way as to ensure that the fibre only comes into contact with water in the stomach, where it is safe for it to swell in size. As well as causing the user to feel full, this action also causes the digestion process to slow down, since it reduces the rate at which digested food leaves the stomach. Some appetite suppressants work in other ways. Hoodia-based appetite suppressants contain a substance called P57, which is present in Hoodia plants. This substance works by imitating the presence of glucose in the brain’s hypothalamus, which basically delays the brain from causing the feeling of hunger, which in turn leaves the user feeling full.

Herbal-based appetite suppressants are preferred over chemical-based appetite suppressants not only because they have far fewer side-effects, but because they can start working very soon after the dose has been taken. For more information on why natural diet pills are a preferred choice, view our full natural diet pills article.

Using Appetite Suppressants with Diet Plans

Because of the way in which appetite suppressants work, it should be understood that they are perhaps better for people who are trying to stick to a healthy diet to lose weight. Appetite suppressants are not going to shift a lot of weight straight away and are most effective when taken in conjunction with a diet plan. If you stick to a diet plan and take an appetite suppressant, you should lose weight because you are eating less and the food you are eating is healthy. If you want to stick to a healthy diet, stop giving into cravings and lose a bit of weight along the way, appetite suppressants are for you.

It can be hard to find a diet supplement that comes with its own diet plan. However, among the many that fail to supply a diet plan, there are the occasional weight loss gems that do. A highly rated slimming product that comes with its own diet plan is Activ8 X. Activ8 X is a liquid weight loss formula that contains 10 active ingredients – all clinically proven. The supplement comes with the AVX diet plan, otherwise known as the ‘hungerless’ diet plan. For more information on Activ8 X and the AVX diet plan, visit the official site.


From this article we can conclude that the supplements that are likely to be most effective at helping suppress appetite are natural and ideally come with a diet plan. Most supplements, however, can be taken alongside any diet plan as long as you adapt the plan to fit in with your supplement schedule. Natural supplements are very effective but also have the added bonus of having few side effects, making taking diet pills an enjoyable experience. Different supplements work for different people which is why you should research products thoroughly before making a final decision. For assistance in finding your perfect diet pill, use our diet pill comparison tool where you can fill in information such as price range or category in order to refine your results.