Updated May 14, 2019.
Published Jul 29, 2015.

ThermoPro is a pre-workout product sold by the reputable company, The Protein Works, who are well-known within the bodybuilding and fitness community. This looks like a decent product that could help with cutting fat somewhat, but we are concerned about some of the ingredients. Bitter orange extract, for example, is pretty dangerous. There are several pricing options, including a 15-day sample size. The company also offer a lifetime guarantee, but the refund will not come in the form of your money back, but you are essentially given a credit note, as you are awarded loyalty points to use on Protein Works products.


  • Company seem reputable and provide full contact details
  • Accurate ingredients list that tells you exactly what you are taking
  • Reasonably priced. You can try out 15 days supply for just £8.49


  • Too many stimulants. May cause serious side effects including heart issues
  • No clinical evidence provided that this supplement has ever been tested
  • The lifetime guarantee does not include a refund
Thermopro is described as a pre-workout formula and a potent cutting aid. If you are a bodybuilder or you want to lose fat but not at the expense of any muscle tone, this supplement claims to help you achieve this aim. With a full ingredients list and an advertised lifetime guarantee, this British made supplement looks good at first glance.

We take an in-depth look at Thermopro to find out more.

ThermoPro Overview

What you need to know about ThermoPro

Thermopro looks strong. As well as a hefty dose of caffeine, it contains ingredients that specifically raise adrenaline levels in a different type of stimulant effect.

Some people will like this, but others may feel jittery and on edge. Sympathomimetic agents –such as synephrine are chemicals that mimic the effects of the flight or fight response and doing this long term can put stress on your body.

This response raises heart rate, energy levels and decreases appetite and will probably be the most noticeable effect. Tyrosine may also keep you awake at night.

What are the side effects of ThermoPro?

Some of the ingredients, bitter orange peel in particular, can cause dangerous side effects. For a full list, please see the Side Effects section below.

How much does ThermoPro cost?

There are several options:

  • 1 x 45 capsule bottle (15 days supply) costs £8.49
  • 1 x 90 capsule bottle (30 days supply) costs £14.99
  • 1 x 180 capsule bottle (60 days supply) costs £26.99
  • 1 x 270 capsule bottle (90 days supply) costs £38.99
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ThermoPro Key Features

Thermopro is a fat burning type supplement that will help you lose fat and not muscle. This process is known as cutting and although this is something that body builders search for, in fact this is what everyone wants. Nobody wants to lose flab and muscle, just flab and you don’t have to spend your life down at the gym to want that!

ThermoPro Key Points

  • Made in the UK in a facility that conforms to GMP (good manufacturing practice
  • Made by The Protein Works a British company based in Cheshire
  • Available in different quantities. 15 days – 3 month’s supply

Thermopro contains stimulants including caffeine, Guarana and Bitter Orange extract plus ingredients believed to have a metabolic effect such as cayenne, and green tea extract. Increasing the metabolism increases the rate at which you burn fat. Stimulants can do this but also some natural non stimulant ingredients such as green tea.

How to Take ThermoPro

Take 1 to 3 capsules daily.

Because of the potent nature of THERMOPRO™, it is important to assess your tolerance first, so we advise starting with 1 capsule daily before training and then progress from there if required.

More experienced users may take 3 capsules before training or spaced evenly throughout the day.

Thermopro contains some natural amino acids that the body uses to regulate fat storage including Acetyl L Carnitine and Tyrosine which is also a natural stimulant that is sometimes taken to combat fatigue. There are B vitamins and chromium a trace mineral that may affect how the body processes glucose (sugar).

In addition, you get a sizeable serving of white kidney bean extract, which may help you reduce your appetite and avoid hunger pangs. White kidney bean extract is high in fibre and stays in your stomach for a long time. The result is that you feel fuller for longer and you don’t suffer from the symptoms of an empty stomach such as pains or acid indigestion.

However, we are concerned about the caffeine content, which is high if you take the three capsules in one hit. We are also concerned about bitter orange extract because this is known to increase heart rate and blood pressure.

Bitter orange can be dangerous. It contains a chemical called synephrine, which is a powerful stimulant, and it will not suit you if you have any heart related medical issues. It is important to remember that heart issues are not always diagnosed or known about until there is a problem.

ThermoPro Concerns:

  • Safety. This supplement does not look very safe
  • Will people take this supplement for 3 months?
  • No real evidence that stimulants provide anything more than temporary weight loss. Is it really worth the risks?

Thermopro is made by a British company called The Protein Works (TPW) who are based in Cheshire – an area in the North West of England that is becoming a centre for UK supplement companies.

The company is very easy to contact and very transparent about their details. The product information guarantees that this supplements and others produced by the company are all made in the UK in GMP (good manufacturing practice) accredited facilities.

Other TPW supplements include a wide range of protein products including powders, Shakes, snacks and supplements. They also cater for the Paleo diet with specific products to support this. They sell a range of pills and supplements to support weight loss, pre work out, vitamins, joint care and more.

What does ThermoPro claim to do?

According to the advertising,

Thermopro from TPW™ is a scientifically advanced formula, developed using cutting-edge, researched natural ingredients.


Its unique formula has been designed to support lean muscle definition.

There are three key features

  • Potent pre-workout supplement
  • Advanced proprietary formulation
  • Potent advanced cutting aid

It contains a precise blend of research supported natural ingredients that have been rigorously tested and proven to be highly effective in increasing the rate at which your body can burn calories at rest.

If the ingredients are supported by clinical research, we feel that the product information should have referenced the details.

Does ThermoPro work?

If you are specifically looking for a stimulant, Thermopro seems to fit the bill. However, you need to be careful when going down this route because it can cause side effects and if you have a medical condition or are sensitive to stimulants, you could put your health under risk.

Synephrine and ingredients that increase adrenaline are potentially dangerous. They come with the risk of cardiac events and could lead to heart attacks or strokes.

According to reports,

Strokes and cardiac arrhythmias have been the major concern about supplements containing the sympathomimetic drug, synephrine.

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ThermoPro Ingredients

Thermopro is a fat burning weight loss supplement. Each serving is equal to three capsules that you can take in one go, or spread throughout the day. Amounts provided here are equal to three capsules.

  • Vitamin B12 (600mcg or 0.6mg): Important vitamin for the function of the brain, nerves and cells of the body.
  • Biotin (600µg): Important B vitamin that helps healthy skin, nerves, metabolism. Some medical opinion is that biotin is present in a normal diet without the need for supplementation.
  • Vitamin B5 (18mg): Also known as pantothenic acid and an essential vitamin for health. In supplement from the RDA is between 5-10mg so in excess here.
  • Chromium (57µg): Trace mineral that may help regulate blood glucose levels.
  • L Tyrosine (600mg): Amino acid that is found in meat so most people do not require supplementation. Works as a natural stimulant because it raises adrenaline levels so can make you feel on edge. Just 150 mg will improve alertness so here in very high quantities.
  • Caffeine (450mg): Most diet supplements contain caffeine and it is ideal for giving you a quick energy boost. It can increase the speed of the metabolism and help fat burning but the effects are often short lived as you become accustomed to use. Contains the equivalent of the recommended daily upper limit for caffeine.
  • N-Acetyl L-Carnitine (300mg): Shown to improve the efficiency of the body to burn use fat as a source of fuel.
  • Bitter Orange Peel (300mg): Also known as Citrus Aurantium, bitter orange peel contains a stimulant chemical called synephrine, which affects the central nervous system. It increase adrenaline so can decrease appetite and pump up energy levels. It does come with associated health risks.
  • White Kidney Bean Extract (285mg): An ingredient that improves our ability to process carbohydrates and prevents them from turning to fat. Kidney bean extract contains fibre and may cause feelings of fullness (satiety).
  • Green Tea Extract (150mg): Healthy ingredient that is high in antioxidants and can help increase the metabolism. According to some clinical investigation, Green tea combined with resistance training may lead to a decrease in body fat. Other clinical research suggests it combines well with caffeine.
  • L-Phenylalanine (75mg): Amino acid found in protein including eggs, meat, fish and milk. The body may use L Phenylalanine to make chemical messengers but it is unclear how it works or if it is effective for weight loss. Can increase blood pressure.
    Source: PHENYLALANINE.aspx?activeIngredientId=653&activeIngredientName=PHENYLALANINE
  • Guarana Extract (21.6mg): Guarana is a South American bean similar to the coffee bean. Like coffee, it contains caffeine so provides the same effects. There is not much else to Guarana beyond caffeine and here in the equivalent of less than a quarter of a cup of instant coffee.
  • Green Coffee Extract (27mg): Research results indicate that slight weight loss may be caused by chlorogenic acid – present in unroasted or green coffee beans, which appears to inhibit glucose into the blood stream. Requires further evidence and in low quantities here.
  • Cayenne Powder (15mg): Some clinical studies suggest that cayenne may increase the metabolism and induce thermogensis. However, it only seems to be effective in much higher quantities.
  • Black Pepper Extract (3mg): Contains a chemical called BioPerine, which may help increase the absorption of the other ingredients in the same way that black pepper can enhance the taste of food.

ThermoPro Side Effects

ThermoPro comes with a health warning to avoid if you are prone to dehydration and to stop or reduce the dosage if sleeplessness, tremors, dizziness, nervousness, headaches or heart palpitations occur.


Avoid if you are pregnant or breast feeding.

THERMOPRO™ was purposely created as a powerful, stimulant based fat loss formula that should only be taken by healthy adults, aged 18-50 years old to help break training plateaus.

ThermoPro Customer Feedback

There are some feedback comments on the product page of the TPW website.

I’ve found these take around 30-45m to kick in but definitely feel a buzz. If you’re petite I’d suggest starting off with 1 and definitely don’t take after lunch time if you want a chance of sleeping at night!

Other customers have mentioned the stimulant effects,

It’s 3am and I am VERY awake! Usually I have no side effects from caffeine but I’ve been on a clean diet for a month & caffeine is one of the things I’ve cut. I took these before my workout this evening without even thinking about that…never again!


When taking one or two of these pills pre-workout I can feel a more intense focus and I sweat buckets. Definitely recommend unless you’re sensitive to such stimulants.

ThermoPro Money-Back Guarantee

Thermo Pro comes with a lifetime guarantee. It is a little misleading because you are not refunded in cash, but instead you are sent The Protein Works loyalty points to spend on other products.

You must obtain an order number for returns. You must use tracked postage and pay the cost of return delivery. The guarantee only applies to products bought via the Protein works website and not third party sites such as eBay and Amazon. The guarantee is valid for an unlimited amount of time. You don’t have to act within a time frame in order to claim it.

Once accepted, your loyalty points will be sent via email within 48 hours.

Where To Buy ThermoPro

You can buy Thermopro direct from the Protein Works website in a choice of quantities:

  • 1 x 45 capsule bottle (15 days supply) costs £8.49
  • 1 x 90 capsule bottle (30 days supply) costs £14.99
  • 1 x 180 capsule bottle (60 days supply) costs £26.99
  • 1 x 270 capsule bottle (90 days supply) costs £38.99

Standard UK shipping is £2.99. You can also choose economy delivery for £1.49 or first class letter post for £1.99. The Protein Works also ships overseas. Delivery rates vary depending on country. You can contact the company for further details.

You can also buy Thermopro via amazon UK. At the time of writing 1 x 90 capsule bottle costs £15.99 plus £2.99 UK shipping. Thermopro is not on sale via Amazon USA.

Watchdog Verdict

Thermopro is going to have a stimulant effect so if you are looking for this, then this supplement will probably work. However, we are concerned about the mix of the different type of stimulants and you may experience side effects. It is fair to say that this is not a healthy way to lose weight and it will not lead to long-term weight loss.

If you have an undiagnosed heart condition, this supplement could be very dangerous.

Many of the non-stimulant ingredients such as green tea are in very insignificant quantities and unlikely to do much. Apart from the white kidney bean extra there does not seem much point to even having them in this formula. Has it ever been tested? We doubt it.

We are not overly impressed with the ‘lifetime guarantee’ either. A credit note is not the same as a cash refund and unless you like the products, it does not really seem worth bothering with.

We love the accurate ingredients label and the fact that The Protein Works are transparent about their contact details. We like that Thermopro is made in the UK.

However, this supplement seems to miss the mark. There are no independent customer reviews, apart from those displayed on the product page, so it seems that Thermopro is just not very popular with customers.

It is an easy decision. We feel that Thermopro is just not safe or effective enough to make it worth taking so we have no other option but to reject it.

How does ThermoPro compare to Phentaslim?

Criteria ThermoPro 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.

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