Diet Pills Online
Diet Pills

Surf the net for information to help you lose weight and chances are you’ll come across plenty of sites selling diet pills and now you can buy Orlistat over the counter in the form of the Alli Diet Pill. But is it worth spending £££s in an attempt to lose lbs. Dietitian Juliette Kellow reports...

Diet Pills Online Review

By Dietitian, Juliette Kellow BSc RD

‘Fool your brain into thinking you’re full!’, ‘Eat all your favourite foods but still lose weight!’, ‘Fire up your body’s fat-burning furnace!’.

These are just a few of the claims you’ll find on websites that sell pills to help you lose weight. And with the promise that you can eat what you want but still lose large amounts of weight in a short amount of time, it’s unsurprising many of us our tempted to buy and try.

But is it safe to buy diet pills from the net? What are the dangers of diet pills purchased online?

Let's take a closer look at diet pills

For many diet pills available online, there’s often very little research – if any at all – to prove their ingredients will actually help you shift those pounds. And even if research has been carried out, it’s usually only one or two small studies, the results of which haven’t been repeated or seen in larger studies.

A new over the counter pill is now available. The Alli diet pill (Orlistat) may be a better bet if a pill is the right choice for you. Read dietitian, Juliette Kellow's Alli Diet Pill Review for the lowdown.

In reality, most dietitians agree that any weight loss achieved is usually due to a change in lifestyle rather than the pills themselves. Indeed, many diet pills come with a reduced-calorie diet (although this is often called an eating plan) and advice to drink large amounts of water every day.

Diet pills or diet plan?

It’s the reduction in calories that causes weight loss, while drinking lots of water helps to prevent hunger kicking. That means, just as the packaging claims, ‘you lose weight, without feeling hungry’ but it's not just because of the pills.

Even if pills don’t come with a diet, there’s evidence that some people unconsciously change their eating and exercise habits for the better when taking a pill they believe will help them lose weight.

So again, it’s far more likely to be diet and exercise that result in weight loss rather than anything magic in the pill.

Many diet pills sold online provide very little information about what they contain, how they supposedly work, for whom they are suitable or any potential side effects.

Lack of information

This lack of information poses a real health hazard. Certain ingredients in slimming pills may interact with other prescribed medications or be unsuitable for people with medical conditions such as diabetes or high blood pressure. Both of which are more common in people who are overweight or obese.

If you’re still tempted to buy, don’t be fooled into thinking you’ll receive more information with the product. Chances are, you won’t!

Dangerous ingredients in diet pills

Even more sinister is the fact that some slimming pills sold on the net contain herbal ingredients that are banned in some countries because they’re considered to be harmful to health.

Worse still, there are no guidelines to control the claims or descriptions made about these products. This means some of these slimming products are described as ‘natural’, giving the impression they are completely safe, when in fact, this couldn’t be further from the truth.

Prescription only

Equally worrying is the fact you can buy slimming pills on the net that should only be available on prescription, including prescription-only slimming pills that are used in America but not recommended in the UK.

While more research has generally been carried out on these types of drugs – and there’s more evidence that they actually work – taking prescription-only drugs without any medical checks can be potentially fatal.

Especially for people with health problems such as high blood pressure or heart disease. That’s why prescribable drugs should only be taken under strict medical supervision, following an initial assessment by a doctor and then regular follow ups whilst taking the pills.

Online pharmacies

It’s also important to avoid being fooled into thinking that a product is safe or effective because of the type of website it’s available from.

Many websites simply provide an online pharmacy, enabling customers to buy a range of diet pills, often at discounted prices. It’s obvious the main function of these sites, just like any shop, is to make money.

In contrast though, some websites take a more subtle approach and are designed to look as though they could be part of a medical establishment. They often provide health or diet information and include pictures of doctors and nurses to give the impression they are credible organisations.

Individual products may also include some ‘research’ or ‘testimonials’ from ‘doctors’ to support their effectiveness. Ultimately though, just like the online pharmacies, the main function of these sites is to sell slimming supplements – and make money.

Lose £s not pounds

It’s worth bearing in mind that a lack of information, little proof they work and potentially putting your health at risk is not the only price you need to be prepared to pay. Chances are you’ll definitely lose pounds – but most significantly, from your pocket!

Instead, WLR recommends spending the cash you might be tempted to fork out for pills, on your favourite healthy foods, a gym membership, new clothes or a pampering treatment to keep you motivated as you lose weight by safe and effective calorie counting!

Here are just a few examples of some of the diet pills and products you can buy online…


Capsiplex is a slimming supplement pill that contains a naturally occurring compound found in chilli peppers (capsicums) that gives them their heat.  It also contains three other ingredients: caffeine, niacin (a B vitamin) and piperine (found in black pepper).

Capsiplex claims to be 100 percent natural and helps you lose weight whilst doing nothing more than sitting at your desk, thanks to its ability to burn up to 278 calories – the same amount as in a hamburger, slice of pizza or two large chocolate chip cookies.

However, there’s insufficient evidence to suggest this product works to burn more calories. One small study involving just 25 subjects doesn’t stand up to medical scrutiny.  The best way to shift those pounds safely and sensibly is to stick to a healthy, balanced diet that’s lower in calories, and get more active.

Ephedra or Ephedrine

Ephedra is also known as Ma Huang, a Chinese herb.

Its active ingredient is ephedrine, a ‘natural’ chemical that stimulates the heart and nervous system. Ephedrine, made in laboratories, is used in drugs to treat asthma and other respiratory conditions. However, ephedrine has also been found to suppress appetite, boost metabolism, enhance sports performance and increase energy.

As a result, until recently, ephedra was often found in many ‘natural’ diet pills and supplements designed for athletes. However, The US Food and Drug Administration (FDA) – the organisation responsible for ensuring that food and drugs are safe for Americans – banned products containing ephedra in 2004, saying there is ‘an unreasonable risk of illness or injury’ from the use of the drug.

Following an extensive study looking at the drug, ephedra was linked to psychiatric problems and was found to raise blood pressure and put additional stress on the circulatory system, leading to heart attacks and strokes.

While many companies removed ephedra from their products in response to this ban – and started labelling them as ‘ephedra-free’ – it’s still possible to buy products that contain ephedra on the net, although WLR actively discourages this.

Many ephedra-free products now use Citrus aurantium or bitter orange extract instead of ephedra. This contains an active compound called synephrine, which is chemically very similar to ephedrine.

Like ephedrine, it acts as a stimulant and is thought to boost energy levels and increase metabolism, so that the body burns more calories. However, it’s also thought to have similar side effects to ephedrine and so WLR recommends avoiding products that contain it.

Sida Cordifolia

Sida cordifolia is a plant that’s been used in India for thousands of years to treat conditions such as asthma, colds, flu and nasal congestion.

In the Western world, it’s often used in diet pills. This is because, like ephedra, Sida cordifolia contains ephedrine, although in smaller amounts.

It’s therefore a weaker stimulant, but nevertheless, it still has many of the side effects and potential health risks and dangers seen with ephedra. Particularly when it’s combined with other stimulants such as caffeine.

Although the FDA has not banned Sida cordifolia, it’s likely to have similar side effects to ephedra and so WLR recommends avoiding products that contain it.

ECA Stack

The ECA Stack contains three drugs – ephedrine, caffeine and aspirin – which, when combined, are thought to boost metabolism even more than ephedrine alone.

This combination is potentially lethal for anyone with a heart condition or high blood pressure as the drugs all act as powerful stimulants.

Products based on ECA combos contain ephedrine so they carry the same health risks as products based on ephedra alone.

Other side effects include insomnia, a dry mouth, irritability, stress, headaches, dizziness, nausea, an irregular heartbeat and trembling hands.

Guarana or kola nut extract are often used to supply a ‘natural’ source of caffeine. Similarly, white willow bark is often used to provide a ‘natural’ source of salicylates, the main active ingredient in aspirin.

Fortunately, following the ban on ephedra, many ECA stack products have been discontinued. However, similar products have sprung up in their place using bitter orange extract or Sida cordifolia (see above) instead of ephedra.

Some examples of different Stacker 3 diet pills available that are based on the principles of the ECA stack include Herbal Thermo Stack E/C/A, Stacker 2 Ephedra Free and Sida Cordifolia Complex. WLR doesn’t recommend these types of products.

Caffeine-containing Pills

Many diet pills contain caffeine, usually in combination with several other stimulating ingredients.

Some common examples of brands include Zantrex and Xenadrine, together with those based on the principles of the ECA stack (see above). The caffeine in these pills is often from plant extracts such as guarana, yerba mate, green tea and kola nuts.

As a result, products are often described as being ‘herbal’ or ‘natural’, inferring they are completely safe. Caffeine stimulates the central nervous system and supposedly boosts the body’s potential to burn fat.

Ultimately though, most diet pills containing large amounts of caffeine have similar unpleasant side effects to drinking excessive amounts of coffee. These include anxiety, an increased heart rate, raised blood pressure, nausea, diarrhoea, restlessness, shaking, irritability and insomnia.

Caffeine is also addictive.

Consequently, WLR recommends avoiding diet pills containing caffeine, especially if you have high blood pressure, thyroid disease, diabetes or heart problems.


This is an appetite suppressant that’s available on prescription in America, but not in the UK.

It’s chemically similar to the amphetamines and stimulates the hypothalamus in the brain to increase the amount of two neurotransmitters (chemicals) – dopamine and noradrenaline. These neurotransmitters stimulate a fight or flight response in the body, which in turn halts hunger and causes a loss of appetite.

Phentermine can cause side effects such as an increased heart rate, palpitations, insomnia, restlessness and raised blood pressure. Plus, in the long term people taking this drug can feel euphoric and so get addicted to it.

It’s unsuitable for people suffering with certain conditions including heart disease, high blood pressure, diabetes, epilepsy or thyroid problems and should only be used by people who have a BMI of 28 or more.

Due to the potentially addictive nature of this drug, the FDA recommends it’s only used for 12 weeks, in combination with a diet and exercise plan and with medical supervision. Adipex and Ionamin are two different brands of phentermine.

It’s also worth pointing out that in the past, phentermine was combined with one of two other appetite suppressant drugs – fenfluramine or dexfenfluramine.

However, these were withdrawn in America in 1997 after research showed they increased the chances of developing problems with the heart valves and high blood pressure in the lungs (pulmonary hypertension).

This combination of drugs – sometimes known as fen-phen – hasn’t been available in the UK since 2000.

In Europe, the authorities that regulate drugs think more research still needs to be carried out on phentermine alone as it may also be linked with heart and lung problems. As a result, phentermine is not available or prescribed in the UK or the rest of Europe.

Consequently, WLR doesn’t recommend buying and trying phentermine.


Sibutramine is an appetite suppressant that’s available on prescription in the UK under the brand name Reductil.

It works by indirectly boosting levels of serotonin and noradrenaline in the brain – two neurotransmitters or chemicals that act on the part of the brain that tells us how hungry or full we feel.

When there are more chemicals in this part of the brain, the brain gets more messages to say we feel full. This means we feel more satisfied with less food, so eat smaller amounts and lose weight.

It’s clinically proven to help people lose weight but should only be used under strict medical supervision and in conjunction with diet and exercise advice.

It’s only suitable for people with a BMI of more than 30 or for people with a BMI of more than 27 who also have other health problems such as diabetes or high blood cholesterol. It should also only be prescribed to people in these categories who have found it difficult to lose weight by diet and exercise alone.

As with any drug, there are side effects, which include headaches, a dry mouth, constipation, difficulty sleeping, an itchy runny nose, a dry, sore throat, raised blood pressure and an increased heart rate.

WLR don’t recommend buying any prescription-only drugs from the internet. If you think you might be a suitable candidate for Reductil, see your GP for advice. Meridia is the brand name for sibutramine in America. Other brand names for sibutramine include Obestat, Sibutrex, Sibutrim and Leptos.


Orlistat is available on prescription in the UK and goes under the brand name of Xenical. It is also now available in the form of the new Alli diet pill which is available over the counter at pharmacies. Read dietitian, Juliette Kellow's Diet Pill Review.

It works by blocking the action of an enzyme called lipase that digests fat in the intestine. This stops around 30 percent of the fat you’ve eaten from being digested and therefore absorbed back into the body.

As a result, fat passes straight out of your body into your stools. This, in turn, means you lose around a third of the calories provided by this fat and so start to lose weight!

It’s clinically proven to help people lose weight but should only be used with a doctor’s consent and regular medical follow-ups. It’s only suitable for people with a BMI of 30 or more, or those with a BMI of 28 or more who have other health problems.

Before being prescribed this drug, you also need to be able to demonstrate that you can lose at least 2.5kg in a month by dieting and exercising alone – and you’ll need to continue with a low-fat diet whilst taking the drug.

Orlistat can have some unpleasant side effects such as frequent wind, an urgent need to go to the toilet, an oily leakage from the bowels, nausea and vomiting. These occur as a result of the extra fat that travels through the body without being absorbed.

Orlistat can also stop the absorption of fat-soluble vitamins such as vitamins A, D, E and K and so your doctor might recommend supplements of these.

WLR don’t recommend buying Xenical from the internet. Instead, if you think you might be a suitable candidate for this drug, see your GP for advice.


Hoodia is the latest buzzword in the world of diet pills.

It’s actually a succulent plant that looks like a cactus and is found in the Kalahari Desert. There are several species of Hoodia plant, but it’s Hoodia gordonii that appears to have slimming powers.

After hearing that Bushmen in the Kalahari had been eating Hoodia for thousands of years to stave off hunger during long trips into the desert, pharmaceutical companies started to take an interest.

Scientists discovered it contained a previously unknown appetite suppressant, which they called P57. This ingredient appears to have similar effects on the nerve cells in the brain as glucose – after eating, the nerve cells sense glucose and start firing to let you know that you’re full.

Hoodia appears to trick the brain into thinking you’ve eaten by making these nerve cells fire as if you were full. However, very few studies have been carried out to establish the safety or effectiveness of Hoodia and it’s still unclear whether there are any side effects associated with taking it, especially in the long term.

As a result, most doctors are unlikely to recognise or recommend this product as an appetite suppressant until considerably more research is carried out.

Nevertheless, in recent years Hoodia has been turned into pills and sold as an appetite suppressant on the internet. However, research shows that many of these products don’t actually appear to contain the active ingredient that allegedly suppresses appetite.

WLR recommends avoiding these diet pills until we know more about the long-term effects of Hoodia gordonii.

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