Updated May 31, 2019.
Published Nov 30, 2016.

Thermaxin is a top quality fat burner manufactured by Astral Nutrition. There is strong evidence that green tea and caffeine can improve the results of resistance training, so Thermaxin is a great choice for anyone who is pretty active and wants to up their results in the gym. There’s a money-back guarantee – a sure sign that the company have complete faith in their products – and the price is very affordable.


  • Contains some good ingredients
  • Reputable looking company – safe to buy from
  • Money-back guarantee


  • Confusion over the caffeine content contained in this supplement
Thermaxin is a fat burner type of weight loss supplement that, according to the advertising, will power you towards your fitness and weight loss goals. It contains eight active ingredients, including a lot of caffeine, and high levels of capsicum extract for added fat burning.

It looked pretty good at first glance, so we took an in-depth look at Thermaxin to find out more.

Thermaxin Overview

What you need to know about Thermaxin

Thermaxin is a fat burner supplement on sale from the British company Astral Nutrition, and is the strongest supplement in their product range. It contains some fat burning favourites, including green tea and caffeine, but we are concerned about the green coffee bean extract because it is not clear whether this part of the formula contains additional caffeine as well. This supplement could well be worth a try if you work out and exercise, but it will not suit you if you have health concerns around heart and blood pressure.

What are the side effects of Thermaxin?

Side effects are mainly caffeine related and may include: jitteriness, headaches, anxiety, increased heart rate and blood pressure, stomach upset, nausea or insomnia.

How much does Thermaxin cost?

Thermaxin is not very expensive compared to some other diet products. Buy from the official website and it costs £29.99 for 60 capsules (one month’s supply).

If you follow Astral Nutrition on Facebook you can obtain a discount code offering you a further 10% off the retail price.

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Thermaxin Key Features

This is a fat burner supplement, so it might suit you if you are looking for some stimulant fire power to motivate your workouts and exercise routines.

Thermaxin contains caffeine, which will not suit you if you are sensitive to caffeine or other stimulants. It will also not be suitable if you have any kind of health condition relating to your heart or blood pressure.

Thermaxin Key Points

  • Each bottle contains 60 capsules (one month’s supply)
  • Go to the Astral Nutrition Facebook page and you can get a 10% discount voucher
  • Will not suit you if you are sensitive to stimulants

One of the principle ingredients is green coffee extract, which at 1000mg per serving and in the form of a condensed extract could deliver a noticeable caffeine effect.

Green coffee bean extract is derived from coffee before it is roasted. Green coffee beans are high in a substance called chlorogenic acid, which is believed to have benefits for heart health, diabetes, weight loss and blood pressure. As we all know, coffee contains caffeine too, and although the caffeine contained in green coffee extract is less than in the roasted variety, we have no way of knowing for sure how much caffeine THIS part of the formula contains. So you will have to proceed cautiously when first using this supplement.

How to Take Thermaxin

Take one pill on an empty stomach before breakfast with 250ml of water. Take another pill 4 hours later with 250ml of water. Do not exceed two pills within a 24 hour period. If you have a sensitive stomach you are advised to take after food. Do not use this product after 7pm, as the caffeine content could cause insomnia. If you’re looking to use Thermaxin as a pre-workout, skip the morning and afternoon capsules and take both capsules 45 minutes prior to your workout with your pre-workout meal.

The other principle ingredient is capsicum extract – derived from the hot chilli peppers and known as a natural thermogenic. It increases body temperature when eaten in its natural form and as a result may help the body burn off calories and fat.

Other ingredients include green tea extract and natural caffeine. There is a lot of positive evidence that this combination is effective for weight loss. Catechins found in green tea are proven to burn fat, especially when used in conjunction with caffeine, and there is also evidence that it is very effective when combined with resistance training.

Thermaxin is a relatively new supplement on the market. It comes from an independent supplements company called Astral Nutrition, who are based in the north of England and is just one in a wide range of products, all targeting weight loss and body building.

Thermaxin Concerns:

  • The caffeine content seems pretty high

Astral Nutrition sell their products via the official website and also on eBay UK. They seem safe to deal with and, reading through the terms and conditions and trawling through the internet, we cannot find any issues regarding dodgy practices, such as signing you up to auto-ship agreements or similar. This looks like a reputable company when it comes to sales practice.

However, we would have liked to have known the origin of the supplements. It is not disclosed where any Astral Nutrition supplements are manufactured, so we cannot guarantee that they are made in the UK and conform to industry standards. It is highly possible that this information has simply been overlooked in the advertising, or it could indicate that the supplements have been imported.

What does Thermaxin claim to do?

Thermaxin is suitable for men and for women and is “an essential fat loss supplement for anyone looking to target a leaner, meaner, healthier physique.”

According to the advertising, the key features are:

  • Features 8 highly effective active ingredients
  • 500mg of polyphenol-rich Green Tea extract per serving
  • Contains a massive 1000mg of Green Coffee & Capsicum per serving
  • Chromium contributes to normal carbohydrate, protein and fat metabolism
  • BioPerine® 5mg per serving for rapid absorption
  • Does not contain any harmful, unsafe or unproven ingredients
  • Perfect for endurance and high intensity training

The product information explains how the supplement will help you,

The ingredients work to contribute to normal macronutrient metabolism, support the maintenance of normal blood glucose levels, heighten mental focus and concentration and reduce the rate of perceived exertion (RPE), allowing you to work harder for longer.

Does Thermaxin work?

We think that Thermaxin will work for some people. You probably need to be pretty active and use this supplement to help your training regime, but it looks like it can help improve results.

There is strong evidence that green tea and caffeine can improve the results of resistance training. In addition, the other ingredients may help the regulation of blood sugars and your metabolism. However, there is this question of the unknown caffeine content. You may find that Thermaxin disagrees with you if you are stimulant-sensitive.

It could be problematic if you have any issues around heart health and blood pressure. Be careful not to train beyond your limits when taking Thermaxin as well.

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Thermaxin Ingredients

Thermaxin comes with a full ingredients list. Many of the ingredients are in concentrated form, so will be stronger than if they were unadulterated.

Serving size is equal to 1 capsule.

  • L Tyrosine (150mg): Tyrosine is an amino acid made in the body and is also available from the protein in your diet. It helps the body convert fat into energy and it is important for mental functioning. It seems to help the brain perform well under stressful conditions and taking 150mg seems to improve mental performance in people who are deprived of sleep. Source:
  • Natural Caffeine (150mg): Most diet supplements contain caffeine as it is ideal for giving you a quick energy boost. It can increase the speed of the metabolism and help fat burning, but some people will find effects can decrease once you get used to it. The equivalent of roughly 2 cups of instant coffee is included here.
  • Capsicum (8.1) (1000mg): When taken in sufficient quantities, some research has indicated that high levels of capsaicoinds, the compound that causes the fiery sensation of chilli pepper, increases the metabolism and promotes fat burning. However, it requires further evidence to prove whether it is effective in supplement form.
  • Green Coffee Bean (40.1) (1000mg): Green coffee is another popular weight loss ingredient, and there is evidence that chlorogenic acid inhibits glucose into the blood stream. However, like so many things, it does require further clinical testing. Despite hundreds of articles about Green Coffee, an investigation found that all random controlled trials were carried out on very small amounts of people for a very limited time. The safety and the effective dose has not been established. Scientists report, “More rigorous trials are needed to assess the usefulness of Green Coffee Extract as a weight loss tool”. Green coffee bean does contain caffeine, but the amounts will vary depending on the production.
  • Green tea extract (20.1) (500mg): Green tea is ordinary tea which has undergone minimal oxidation in the manufacturing process. It has been widely studied for its effects upon health and weight loss. Results are impressive. Green tea retains more health giving antioxidants than ordinary tea and can have real benefits. Green tea is rich in antioxidants called polyphenols, which are proven to help prevent against cell damage. In addition, green tea can be effective for supporting weight loss. When combined with caffeine these functional ingredients have the potential to produce significant effects on metabolic targets, such as thermogenesis and fat oxidation.
  • Black pepper extract (5mg): Black pepper contains a chemical compound called Bioperine that seems to enhance the effects of other ingredients when used in a supplement, increasing bioavailability.
  • Chromium (200mcg): Trace mineral that the body needs in very small amounts as here. It has been tested as a treatment for diabetes because it seems to help control how the body controls sugar levels. It also seems to reduce cholesterol and blood fats.
  • Iodine (150mcg): An essential chemical element that the body needs but cannot manufacture, yet is crucial for health and well being. It is used by the body to regulate the thyroid hormone and medicinally as a treatment for radiation poisoning. It can cause serious side effects if taken in excess, but the tolerable upper limit for adults is 1100mcg per day, so is included in safe levels here. There is no evidence that taking iodine will help weight loss.

Thermaxin Side Effects

Thermaxin may cause side effects. These can include:

  • Jitteriness
  • Headaches
  • Anxiety
  • Increased heart rate and blood pressure
  • Stomach upset
  • Vomiting
  • Nausea
  • Insomnia


Not suitable for individuals under 18. Avoid if you are pregnant or breast feeding. The product information advises you to speak to your doctor first if you have high blood pressure and/or are on blood pressure medication. You should seek medical advice first if you are diabetic or have issues around the thyroid as the supplement may interfere with medication.

Thermaxin Customer Feedback

There are positive customer testimonials for Thermaxin posted on the product page, so we cannot guarantee these are totally impartial or whether any negative comments have been filtered out.

Comments include,

Top product. Sweating like a mad man! Loads of energy in the gym. Happy 🙂

Had a few mates at the gym raving about this product so I finally decided to grab a couple of bottles. Very impressed, definitely the strongest fat burner I’ve used and I’ve pretty much used them all.


These and the CLA had me soaking with sweat at the gym during my cardio. Appetite is way down too. Bit expensive, but worth it

Thermaxin Money-Back Guarantee

There is a 30-day money-back guarantee provided for all Astral Nutrition supplements.

Where To Buy Thermaxin

Thermaxin is not available in the shops. The best place to buy it is via the Astral Nutrition website. It is also available via eBay UK.

Watchdog Verdict

Thermaxin looks pretty good in our opinion. This is a simple weight loss supplement that may help improve your results if you work out or exercise. We always like the green tea/caffeine combination because it is effective, and we like that Thermaxin does not contain novelty ingredients, such as weird extracts that nobody has ever heard of. However, we are concerned about the potentially high caffeine content of the green coffee bean extract.

As you are covered by a 30-day money-back guarantee with Astral Nutrition products, we think Thermaxin could well be worth a shot.

You can buy Thermaxin here:

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

2 comments on 'Thermaxin'

  1. I am confused by this article which states that you take the pills on an empty stomach with 250ml of water. The actual pack instructions state that the pill must be taken with food and 500ml of water.The accompanying leaflet states that you never take this pill on an empty stomach. Please clarify.

  2. Just purchased this product and took 1 dosage today. I am going to take 1 dosage per diem with or right after lunch to see if there is any benefit either in weight loss or well being

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