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Variations and types of diet pills

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If you’re trying to lose weight and finding it difficult, you’re not alone. The habits of cutting back on calories, eating healthier foods, and exercising regularly can be difficult to maintain – especially if you’re trying them for the first time.

When faced with a long and challenging weight loss journey, many people are keen to turn to diet and slimming supplements. While certain diet pills can be a good way to achieve weight loss, it’s important to take the right ones, and to use them in a safe way.

To find out which diet pills are safe and effective, read on. And remember, before you try any weight loss treatment or diet, it’s always a good idea to speak to your GP first.

Do all diet pills do the same thing?

Diet pills work in different ways. Some reduce the amount of fat digested by the body, while others are said to speed up the metabolism or suppress the appetite. Read our guide about diet pills and what they do for more information. 

What’s important to note is that diet pills should never be a substitute for diet and exercise. You’ll need to eat a healthy, balanced, and varied diet and do regular exercise to benefit from the treatment.

Which diet pills actually work?

Plenty of diet pills have been shown to effectively promote weight loss in clinical trials. The problem is that not all of them are safe!

In the UK, lots of time, money, and research goes into working out which treatments are both safe and effective for weight loss, so you should only ever buy and use diet pills that have been licensed here.

What does orlistat do?

Orlistat is the only weight loss pill that is both licensed for use in the UK and recommended as a weight loss treatment by the NHS. It works by preventing the body from digesting some of the fat in your diet. Instead of digesting the fat, your body passes it out in your poo.

Orlistat is available as a prescription treatment or over the counter. On prescription through LloydsPharmacy Online Doctor it’s available under the brand name Xenical. As an over-the-counter treatment it’s called alli. Prescription orlistat reduces the digestion of about a third of dietary fat. Alli reduces the digestion of about one quarter.

You can be prescribed Xenical if you have a BMI over 30, or if you have a BMI over 28 and weight-related health issues. Alli can be administered over the counter by a pharmacist to most people with a BMI over 28. A pharmacist in-store and online will be able to make sure alli is safe for you to take.

One trial of Xenical showed that 60% of patients lost at least 5% of their baseline bodyweight after taking the treatment for 12 weeks.

What do fat binder pills do?

Fat binder pills are another popular type of diet pill. They’re licensed for use in the UK, however they’re not approved as a treatment by the NHS because there haven’t been enough studies to show that they’re effective as weight loss aids.

Fat-binding pills like XLS-Medical Fat Binder are said to work by binding dietary fat to fibre. Rather than being digested, the fat passes through the body. Although the NHS hasn’t approved this pill’s active ingredient, Litramine, studies such as this one have found that it helps to promote weight loss.

If you want to try fat binders, make sure you take them as part of a healthy lifestyle.

What do fat burner diet pills do?

Fat burner pills are a popular type of weight loss supplement containing an active ingredient that is said to “burn fat” – normally by increasing your metabolism. They often contain natural active ingredients such as coffee beans or green tea.

There are different fat burners which are all said to work in slightly different ways. “Thermo fat burners” might contain caffeine, guarana, or capsaicin, and are said to work by increasing the metabolism which produces heat. “Lipolytic fat burners” are said to work by helping to break down fat cells and making them easier to absorb and use.

In general, there’s very little evidence to suggest that these kinds of fat burners work. While some of the ingredients, including caffeine, have been shown to boost the metabolism, it’s thought that the weight loss effects would be very minimal.

What do appetite suppressants do?

Appetite suppressants are diet pills that reduce your appetite, causing you to eat less across the day.

In the past, appetite suppressants have been used in the UK, but many are now banned. All have been because of major safety concerns.

You shouldn’t try to buy these on the internet, even if they are legal in other countries.

How do I know which type of diet pill is best for me?

Diet pill How it works How effective is it? Where can I get it?  Is it NHS approved?
Xenical/Orlistat Reduces digestion of dietary fat by  1/3 60% of patients lost at least 5% of their body weight in 3 weeks Prescription from your GP or LloydsPharmcy Online Doctor Yes
alli Reduces digestion of dietary fat by about 1/4 55% of patients lost at least 5% of their body weight in 6 months Over the counter or online Yes
Fat binders Binds fat to fibre to prevent it being digested Some clinical studies shown ingredients such as Litramine to be effective Health food shops and pharmacies No
Fat burners Typically boosts metabolism to speed up "fat burning" Very little evidence to suggest they're effective Health food shops and pharmacies No

What other weight loss methods are available at LloydsPharmacy?

We offer a weight loss service that can be administered by our pharmacists without the need to visit your GP first.

Our weight loss service is a daily weight loss injection that works by reducing your appetite. After an initial consultation where you’ll learn how to use the product, you can take it home and administer the injections yourself.

Weight loss service