Updated Nov 11, 2021.
Published Jan 3, 2017.

Thermopure, manufactured by MyProtein, is a thermogenic supplement (as you could probably tell from the name). It is designed to boost performance in those who already lead an active lifestyle. The price is so good, and the company so reputable, it’s no wonder this is our favourite energy-boosting product on the market. It works too; for such a well-priced supplement to have a decent list of ingredients is a real rarity.


  • Cheap compared to other products
  • MyProtein is a reputable company
  • Good for boosting the performance of those with active lifestyles


  • No money-back guarantee
  • Not as effective for those who don’t already work out and exercise frequently
Thermopure is a thermogenic supplement sold by MyProtein. Although they state that the product is thermogenic, and that it reduces fatigue and tiredness, they don’t actually claim that the supplement will cause direct weight loss, just that it supports weight-loss goals.

We take an in-depth look at Thermopure to see if it is an effective product.

Thermopure Overview

What you need to know about Thermopure

Based on customer reviews, Thermopure appears to be very good at boosting energy levels – as this is the only claim that the company make about the product, it is very honest in this regard. It does also seem to have some potential to boost weight loss efforts, but as the reviews are not very focused upon this aspect, this is based largely upon the ingredients profile. We believe that Thermopure may boost the rate of weight loss in someone who is already dieting and exercising, but it is unlikely to be able to counteract a sedentary lifestyle coupled with persistent overeating.

Thermopure could be a good introduction to diet pills and pre-workout supplements, thanks to its effective ingredients and cheap price tag; anyone who has used lots of fat burners and strong stimulant-based supplements in the past, such as bitter orange or yohimbe (or Ephedra and DMAA which are both now banned), may find Thermopure somewhat milder. So although it isn’t as potent as those sort of products, it is much safer.

What are the side effects of Thermopure?

There shouldn’t be too much of a side effect risk. Sweating is the main one, as this is a thermogenic. If you are sensitive to caffeine you may experience nausea, headaches, fatigue, or heartburn.

How much does Thermopure cost?

The product costs £25.99 for a pot of 180 capsules, which will last you for two months if you take the recommended dose of three capsules per day. A bottle of 90 capsules (one month’s supply) is just £15.49.

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Thermopure Key Features

Thermopure is described by the manufacturers as more of an energy booster and all-round performance enhancer, not as something that directly causes fat loss.

Thermopure Key Points

  • A MyProtein product
  • Energy booster/pre-workout product
  • Thermogenic ingredients

Thermopure is aimed at any male or female athlete, bodybuilder or sports enthusiast who is looking for a blend of key nutrients and minerals in an easy-to-consume capsule.

How to Take Thermopure

Directions for use are as follows: Consume 3 capsules daily. Best taken on an empty stomach before exercise. On non-exercise days, consume 1 capsule in the morning, afternoon and evening.

Thermopure is manufactured by MyProtein, a sports nutrition company. They can be contacted either through the chat function on their website, or using the contact details found on their official website.

Thermopure Concerns:

  • No money-back guarantee
  • Not as effective for those who don’t already work out and exercise frequently

MyProtein stock a huge range of products, including protein-based snacks and powders, a range of supplements, branded clothing, and gym accessories. They are one of the biggest names in the bodybuilding and fitness world, with a very good reputation amongst customers.

What does Thermopure claim to do?

MyProtein make the following statement about the benefits and effects of Thermopure.

Our formula of essential vitamins and popular ingredients including green tea and black pepper extracts — that’ll boost your everyday wellbeing, with caffeine increasing endurance performance, and chromium supporting your metabolism to help you on your weight-loss journey.

Does Thermopure work?

When trying to establish whether a product will actually work, we look at the ingredients used, the quantities that they are used in, and also turn to customer reviews, to see how the product works in practice.

There are lots of ingredients in Thermopure that have been associated with boosting the metabolism and increasing the speed of weight loss, including caffeine, cayenne, and green tea extract. Their effects are all considered ‘small but significant’; they may boost the rate of weight loss in someone who is already dieting and exercising, but they are unlikely to be able to counteract a sedentary lifestyle coupled with persistent overeating.

Chromium could potentially aid a very tiny amount of weight loss over a prolonged period of use. B vitamins are usually found in adequate quantities in a balanced daily diet, but many companies include them anyway in their products, as a deficiency can hinder weight loss attempts.

So overall, it’s not a bad mix of ingredients. We think it will work for people who exercise frequently, but it’s not going to be a miracle pill for people who don’t lead an active lifestyle.

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Thermopure Ingredients

The ingredients used in Thermopure are detailed below. The ingredient quantities listed are per serving of three capsules.

  • Vitamin B6 5 mg (357% RDA): Vitamin B6 has several important functions in the body, including ‘allowing the body to use and store energy from protein and carbohydrates in food’. Whilst taking excess amounts of vitamin B6 will not infinitely improve this ability, a deficiency could make it more difficult to lose weight. Vitamin B6 is naturally present in a wide variety of foods, including meat, cereals, bread and vegetables, and is often included in fortified breakfast cereals.
  • Vitamin B12 21 µg (840% RDA): Vitamin B12 is naturally present in many foods, primarily meat, fish, and dairy products. It has several roles, including aiding in releasing energy from consumed food, and keeping the nervous system healthy. It may be that a deficiency hinders weight loss, but taking excess amounts could be, according to the NHS, potentially harmful.
  • Chromium 120 µg (300% RDA): This is used primarily to lower fasting blood sugar levels and to lower insulin levels in people who have type 2 diabetes. In terms of its potential effect upon weight loss, it is possible that taking chromium picolinate by mouth for two to three months might produce a small weight loss of about 1.1 kg.
  • Green Tea Extract 375 mg: Green tea is high in a group of antioxidants called catechins. Studies have suggested that catechins increase thermogenesis in the body, whilst caffeine increases energy expenditure by boosting the metabolism slightly for a few hours.
  • L-Tyrosine 200 mg: Some people use L-Tyrosine as an appetite suppressant, but there is little clinical evidence that it is effective for this use. Large doses of tyrosine may be useful for increasing alertness, especially in people who are sleep deprived.
  • Caffeine 198 mg: Numerous studies have shown that caffeine boosts energy levels and alertness, as well as mildly boosting the metabolism. The effects shown in studies are small, and some studies are inconclusive.
  • L-Theanine 125 mg: This amino acid may play a small role in weight loss, as well as increasing feelings of relaxation. It may also reduce the negative side effects of caffeine, although there is seemingly no strong clinical evidence to support this claim.
  • Cayenne Pepper 50 mg: Capsaicin is found in Cayenne pepper and is thought by some to play a role in weight loss. Some studies suggest it could suppress the appetite mildly, whilst others suggest that the heat causes a thermogenic reaction in the body, burning more calories for a period of time. However, there are also studies that show cayenne has little or no effect upon weight loss attempts.
  • Black Pepper Extract 5 mg: Black pepper extract is used for increasing the bioavailability of nutritional compounds. In other words, it increases the amounts of nutrients that are absorbed into the body in the digestive tract. It may also increase the absorption of various drugs, which may lead to potential side effects.

Thermopure Side Effects

Side effects are likely to be quite mild, if there are any at all.

Although Tyrosine is tolerated generally in very high doses, it can cause some side effects including nausea, headache, fatigue, heartburn, and joint pain.

Caffeine can cause side effects such as headaches, increased heart rate, increased blood pressure, heart palpitations, increased urination, dehydration, jitteriness, dizziness, and insomnia. Green tea can also cause constipation. Theanine causes a state of relaxation without drowsiness, and may help to counteract some of the potential side effects of caffeine, such as jitteriness. Consumers should still ensure that they do not take this supplement or any other source of caffeine within five hours of going to bed, as caffeine can interfere with sleep cycles.

Black pepper extract increases the absorption of caffeine and other compounds from the digestive tract into the bloodstream; this effectively makes the doses used higher, but can increase the chances of side effects occurring and increase the chances of accidental overdose from prescription medication.

Cayenne can cause heart burn and indigestion, as well as increased sweating.


Do not exceed the stated dose. Not suitable for pregnant or breastfeeding women. Not suitable for those who are sensitive to caffeine, or anyone who has any heart related conditions, including but not limited to high blood pressure. Not suitable for those under the age of 18. We recommend not to exceed the recommend suggested serving. Not suitable for anyone who is taking any medications, whether over the counter or prescription, as black pepper extract can increase the chances of side effects and accidental overdose.

Thermopure Customer Feedback

There are plenty of customer reviews for Thermopure on the official MyProtein sales page for the product. The majority of the reviews are either four or five star rated, but there are a few mixed opinions and negative reviews. We like that MyProtein don’t edit the customer reviews or take out the negative ones. This way we get a full, unbiased picture of what the product is all about.

I’ve been using Thermopure for around 8 weeks now, and taken about 30 mins before my training session gives you a really good kick. I’m not a particularly sweaty person, but taking these defs makes me one. Good value for money, one pot lasts me around 4-6 weeks.

This is the 3rd round of these I have purchased and they are brilliant! They give me a great buzz just before my workout on training days when I pop 3! (3 is a serving) and they take the edge off on non-training days throughout. I don’t drink coffee, and stay away from caffeinated drinks so this could be a factor to consider if you already OD on caffiene. The sweat this gives me is unreal, but you know it’s working! This product has helped me burn off almost 2 stone in 3 months. I would recommend it to anyone! The tablets are average size (about the size of 2 small peas side by side) and pretty easy to swallow. I find tilting my head forward and getting them to float is the fastest way to take 3 at a time.

I bought this Thermopure with low expectations, not because it was from Myprotein, which I think are a great supplement company, but because of how low the price was. In my experience, if it’s cheap, it’s not very effective. It recommends that on rest days you take 2 to 3 tablet throughout the day, this for me did next to nothing. I used these mostly for the energy benefits, there were hardly any. Taken before a workout though, I could feel a slight pick me up with these, but nothing to rave about, but to be honest, for the price I can’t complain. As long as you just want a fat burner, I’m sure the ingredients do exactly that. As energy goes, if you’re taking them while dieting, I’d go with something stronger.

I was sceptical about these before ordering and did plenty of research – the my protein video put a lot of my fears to rest and I have been very pleased since receiving them. They are like rocket fuel and allow you to really get the most out of a workout, and you really get a nice sweat going too. If your nutrition is on point then this will certainly enhance your performances in the gym or sports field and enable you to go one step further – capsules are small enough to take without gagging.

Gives you some focus in the gym, but no more than a couple cups of coffee to be honest. but if you don’t have the time for that then this is a good product. Does aid in fat burning, but its not a sub for a bad diet.

Thermopure Money-Back Guarantee

There is no money-back guarantee offered by MyProtein for this supplement.

According to the official MyProtein website, the returns policy is as follows:

You have 14 days to cancel your order under our 14 day return period policy, which starts on the day after you received the item.

All items must be returned unused and in the original packaging as they were in when received by you.

Please ensure that when you receive an item that you take reasonable care of it when trying it/inspecting it eg. please ensure that any security seals or tags are still intact.

While we usually disapprove of supplements not having a money-back guarantee, the price is low enough here for it not to seem like too much of a risk to try.

Where To Buy Thermopure

Thermopure can be purchased from the official manufacturer’s website. The product costs just £15.49 for 90 capsules (a month’s supply), or £25.99 for 180 capsules. A bottle of 180 capsules will last between 60 and 90 days, depending upon the desired daily dosage. Delivery charges may apply.

Watchdog Verdict

We quite like Thermopure. MyProtein are a well-respected fitness and nutrition brand, and this is a decent budget option.

There is no money-back guarantee offered by the manufacturers, and their returns policy is only valid for 14 days on unopened products. However, the product is very cheap compared to many other diet pills. If using the maximum daily recommended dosage, Thermopure will cost around 43p per day to use; we have seen other weight loss supplements that can cost two or even as much as three pounds per day to use, so this is a very affordable option.

There are some side effects that could occur whilst taking this supplement. Anyone taking medications, who has cardiac related health issues, or who is sensitive to caffeine should not use this supplement, but if these restrictions are followed, unpleasant side effects appear to relatively uncommon. Increased amounts of sweating appear to be the most common side effect; this is because Thermopure contains thermogenic ingredients which raise the consumer’s body temperature to burn calories. This is a normal side effect of thermogenic supplements, so nothing to worry about, just something to be aware of.

Overall, we feel that Thermopure may be of benefit to those who are fairly active and want to boost their energy for wourkouts, but may not be effective for weight-loss for those with a more sedentary lifestyle.

How does Thermopure compare to Phentaslim?

Criteria Thermopure Comparison Phentaslim comparison
Clinically Proven Ingredients
Side Effect Free
Positive Customer Reviews
24/7 Support
Money-back Guarantee

Disclaimer: Our reviews and investigations are based on extensive research from the information publicly available to us and consumers at the time of first publishing the post. Information is based on our personal opinion and whilst we endeavour to ensure information is up-to-date, manufacturers do from time to time change their products and future research may disagree with our findings. If you feel any of the information is inaccurate, please contact us and we will review the information provided.

Have Your Say

5 comments on 'Thermopure'

  1. I was using another caffeine based supplement from MP, MyThermo which contained many of the ingredients from thermopure but also bladderwrack which contains iodine and unfortunately this led to me suffering severe acne so stopped using them immediately once I knew the source. MP have suggested thermopure as an alternative and shouldn’t have the same side effect, any comment on whether this is common in these supplements?

  2. Given that Thermopure is not marketed as a diet pill there’s not much point in reviewing it as one. The rejected Stamp is ridiculous. What is being rejected? Nobody said it was a diet pill. I would reject the idea of diet pills and dieting. Try regular exercise, eating properly and taking responsibility for your body instead.

  3. The following is not true.

    “Unfortunately, because of the layout of the website, only a few of the most recent reviews are visible, and so it is not possible to see why a few customers gave negative feedback about Thermopure.”

    You can view all of the reviews on mp. There’s a scroll bar that is fairly easy to miss.

  4. Hi,

    I am using thermopure from myprotein, I have not seen any weight loss but when I workout then I see dramatic increase in body temperature. This is my first week and I do heavy lift & high cardio, aiming to reduce fat from the waist.
    I will keep you posted

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