Reflex Nutrition Thermo Fusion Fat Burner Review

Reflex Nutrition Thermo Fusion fat burner

Thermo Fusion by Reflex Nutrition is a fat burner product designed to complement a healthy diet and exercise regime. The product is not marketed as a miracle pill. However, the company claims that it has been “formulated to outperform all other diet aids”.

This is quite a statement to make. Let’s see if this fat burner is as great as it claims to be.


  • Contains some proven thermogenics like green tea and caffeine
  • No proprietary blend
  • Recommended daily dosage – 4 capsules – ensures even supply of ingredients throughout the day
  • The company offers a full money back guarantee – make sure you read the T&Cs though


  • Contains low amounts of caffeine and green tea
  • Lack of evidence supporting the benefits of Acetyl-L-Carnitine or of Alpha Lipoic Acid
  • Lack of research looking at the long-term side effects of Acetyl-L-Carnitine
  • No appetite suppressant in the formula
  • One bottle won’t last you for a month if you take the recommended daily dose of 4 capsules

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What other people say about this product

I’ve only found a few reviews from customers who purchased this product from Amazon. The majority of them seem favourable. However, some point it out that this is not a miracle pill. It needs to be combined with healthy and balanced diet and regular exercise for it to work. This is also advised on the company’s website.

Reflex Nutrition Thermo Fusion Fat Burner Amazon reviews

Dosage – How to take Reflex Nutrition Thermo Fusion fat burner

The company recommends to start by taking 2 capsules per day half an hour before meals (breakfast and lunch for the first two days). This is to assess tolerance. This is always a good idea before starting on a new supplement of any kind. If it feels right after the first two days, the maximum recommended daily dosage is four capsules. One before each meal.


The cost of this product will vary depending on where you purchase it from. If you are buying it through the company’s website, a bottle of 100 capsules will cost you around £30. Bear in mind, that one bottle will not last you a full month if you take the recommended daily dose of 4 capsules.

The company offers free shipping on orders over £20 and on all products shipped within the UK.

The cost of Reflex Nutrition’s Thermo Fusion ranges from £15 a bottle to around £35 a bottle depending on which online retailer you buy it from.

Where can I buy it?

The product can be purchased through the company’s website, but it is also available on Amazon and through a number of other online supplement retailers.

The company offers full money back guarantee, but be sure to read the terms and conditions before you buy the product. This money back guarantee may not be applicable if you buy the product from other online retailers or from Amazon.

Delivery conditions may also differ from one retailer to another so make sure you read all the small print to avoid any disappointment.

Top 3 recommended fat burners


Thermo Fusion contains a number of ingredients that are clear on the label. Their quantities are also clearly visible which is a great start.

L-Carnitine Tartrate

The main ingredient in this product L-Carnitine Tartrate. It is a form of Carnitine, an amino acid that has been linked to a number or claims including weight loss. A daily serving of 4 capsules contains 800 mg.

Although this is the main ingredient in this fat burner, this type of Carnitine is linked to better performance output and less fatigue after exercise, not to fat loss. This is still beneficial if you are doing regular exercise. However, I would like to think that the main ingredient in a fat burner will help you to burn fat.


The product also contains another form of Carnitie, Acetyl-L-Carnitine (240 mg per 4 capsules). There has been claims by other companies that this form of L-Carnitine is absorbed faster than the standard L-Carnitine and therefore it’s a more effective ingredient to use.

Studies found some supporting evidence that Acetyl-L-Carnitine can help to reduce the body’s carbohydrate consumption. These same studies claims that it instead increases the use of fat stores to turn into energy. However, according to reserach, this depends on the intensity of the exercise1.

Despite some promising research, there’s still very little supporting evidence backing Acetyl-L-Carnitine’s effectiveness as a fat burner ingredient.

Reflex Nutrition Thermo Fusion Fat Burner ingredients


The second key ingredient of this fat burner is DL-Phenylalanine and the product contains 400 mg per 4 capsules. It is also an amino acid and is a type of Phenylalanine.

The “D” form is synthetically produced and DL-Phenylalanine has been used in products for pain relief2 as well as in products treating minor depression due to it’s mood boosting properties3. Again this is not an ingredient that has links to fat loss. It seems strange that a fat burning product contains 2 key ingredients that are not supporting fat loss.

Green Tea, Cayenne Pepper and Caffeine

Thermo Fusion also contains some green tea (240 mg per 4 capsules), cayenne pepper extract (200 mg per 4 capsules) and caffeine (160 mg per 4 capsules). These ingredients are proven natural thermogenics. A number of studies linked them to fat loss, especially green tea and caffeine4,5,6,7. All three achieve this by increasing the body’s metabolism, enabling it to burn more fat.

Although these are proven thermogenics, the amounts in the product are quite low. For a fat burner to be effective, the amount of green tea is recommended to be around 500 mg per daily dose. And the amount of caffeine somewhere between 250 and 300 mg per daily serving.

Cayenne pepper has also been shown to have some appetite suppressant properties, but it is not as effective as some other natural appetite suppressants like glucomannan8,9.

Alpha Lipoic Acid (ALA)

Alpha Lipoic Acid (ALA), an antioxidant is also part of the formula. A daily dose of 4 capsules contains 200 mg of ALA. There is very little research into this ingredient’s fat loss properties. Furthermore, existing studies used considerably higher doses of ALA (around 600 mg per day) than the amount found in this product. Therefore, it is not certain if this ingredient contributes to fat loss in any way.


The product also contains 120 mg of Choline in a daily dose of 4 capsules. Our body produces choline by using other nutrients. It is not a vitamin, but has close ties with the different B vitamins. It was believed for a long time that our body was able to produce sufficient amounts. However, recent research has shown that we may need supplementation when it comes to choline.

This ingredient has been shown to help promote higher rate of lipolysis in the kidneys, liver and gallbladder, helping the body burn fat faster whilst also lowering cholesterol.

The recommended daily dosage for choline to help achieve weight loss goals is somewhere between 300 and 500. This product seems to contain considerably less than that.

Find out what really works and what to avoid on
– Best and worst fat burner ingredients –

Potential side effects Reflex Nutrition Thermo Fusion fat burner

People may experience side effects due to the caffine in this product. So if you are intolerant or sensitive to caffeine, this product may not be right for you.

Due to its mood boosting ability, DL-Phenylalanine may interfere with certain antidepressant drugs. So if you are taking any such medication, it is best to consult with your doctor before taking this fat burner.

Furthermore, there is little research into the potential long-term side effects caused by Acetyl-L-Carnitine or L-Carnitine Tartrate especially when combined with stimulants such as green tea.

Finally, the company advises on their website that Thermo Fusion is not for use by individuals who you suffer from high blood pressure.

Final Verdict on Reflex Nutrition Thermo Fusion fat burner

After reviewing this product and its ingredients, I would give Thermo Fusion an above average 3.5 stars out of the possible 5.


The product starts out great. It has all its ingredients and amounts clearly visible on the label. It also contains proven, natural thermogenics like caffeine and green tea. However, the amounts in the daily dose seem to be on the low side for maximum effectiveness.

The two main ingredients of this product L-Carnitine Tartrate and DL-Phenylalanine seem to be mainly linked to benefits other than fat burning. L-Carnitine Tartrate has been found to lead to increased performance during work outs and better recovery after exercise. Whilst DL-Phenylalanine has been linked to boosting mood.

Both of these properties are great, but not the main aim of a fat burner supplement.

Furthermore the Alpha Lipoic Acid found in the formula has little evidence behind its effectiveness as fat burner component.

The product also contains Choline which has been shown to help increase the lipolysis rate in the body, in turn helping to burn more fat. However, the amount found in a daily dose is substantially less than the recommended amount to achieve weight loss.

One downside of this product is that it doesn’t have an appetite suppressant component. Therefore, making it less effective than dual action fat burners.


The daily dose of 4 capsules ensures that there is an even supply of ingredients to your body throughout the day.

All in all not a bad product. However, a rethink of the ingredients and their amounts could help to ensure the product contains sufficient amounts of each vital ingredient to achieve the required fat loss results.

The addition of appetite suppressant ingredients could also improve this product and potentially make the product more effective. There are products out there at around the same price point that have a better ingredients profile and in more effective doses.

Check out my #1 recommended fat burner supplement Instant Knockout

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  • A great natural product with an impressive list of ingredients
  • Highly effective thermogenic ingredients combined with proven and natural appetite suppressant ingredients
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  • Gives you a great boost of energy before workouts




Read the full review on Instant Knockout

Supplements should never be taken in place of a healthy diet and regular physical activity. So, you should always aim to get these two key pillars right first.

If you need some help with exercise, you can check out my post on Muscle Building and Fat Burning Exercises.

Alternatively, you might want to invest in an online workout guide like Boss Workouts or hire a personal trainer if you prefer that.

Muscle building and fat burning exercises

You can also check out my post on healthy meal ideas in aid of weight loss if you need some inspiration.


1. Constantin-Teodosiu, D., Greenhaff, P. L., Macdonald, I. A., Marimuthu, K., Stephens, F. B. and Wall, B. T. (2011).
Chronic oral ingestion of l‐carnitine and carbohydrate increases muscle carnitine content and alters muscle fuel metabolism during exercise in humans. The Journal of Physiology

2. McCarty, M. F. and Russell, A. L. (2000). DL-phenylalanine markedly potentiates opiate analgesia – an example of nutrient/pharmaceutical up-regulation of the endogenous analgesia system. Medical Hypotheses, Vol. 55, Issue 4, pp. 283-288.

3. Beckmann, H., Ludolph, E. J. and Strauss, M. A.  (1977). Dl-phenylalanine in depressed patients: An open study. Journal of Neural Transmission, Vol. 41, Issue 2-3, pp. 123-134.

4. Cardoso, G. A., Cesar, Mde C., Donado-Pestana, C. M. and Salgado, J.M. (2013). The effects of green tea consumption and resistance training on body composition and resting metabolic rate in overweight or obese women. Journal of Medicinal Food, Vol. 16, Issue 2, pp. 171-178.

5. Hursel, R., Janssens, P. L. H. R., Martens, E. A. P. and Westerterp-Plantenga, M. S. (2013). Acute Effects of Capsaicin on Energy Expenditure and Fat Oxidation in Negative Energy Balance. PLOS One, Vol. 8, Issue 7.

6. Graham, T. G. (2001). Caffeine and Exercise: Metabolism, Endurance and Performance. Sports Medicine, Vol. 31, Issue 11, pp. 785–807.

7. Wilcox, A. R. (1982). The effects of caffeine and exercise on body weight, fat-pad weight, and fat-cell size. Medicine and Science in Sports and Exercise, Vol. 14, Issue 4, pp. 317-321.

8. Martinussen, T., Møller, P., Reinbach, H.C., Smeets, A. J. and Westerterp-Plantenga, M. S. (2009). Effects of capsaicin, green tea and CH-19 sweet pepper on appetite and energy intake in humans in negative and positive energy balance. Clinical Nutrition, Vol. 28, Issue 3, pp. 260-265.

9. Smeets, A. J. and Westerterp-Plantenga, M. S. (2009). The acute effects of a lunch containing capsaicin on energy and substrate utilisation, hormones, and satiety. European Journal of Nutrition, Vol. 48, Issue 4, pp. 229-234.