Updated: 10/06/2015 - Sponsored by Leptigen

Thermofuel Review - Does This Fat Burner Work? Are side effects and dangerous ingredients deal breakers?

Editor's Review: 3.5 / 5.0

thermofuel-product-imageThermofuel caught the attention of some dieters, so we chose to dig deeper into the ingredients, side effects, customer service and clinical research. We combed through hundreds of user comments and reviews. We then condensed, refined and summarized to give you the info you need.

EDITOR'S TIP: Substitute Thermofuel with a proven fat burner such as Leptigen for better results.

What You Need to Know

Firstly, Thermofuel is a fat burner that has caffeine, synephrine, acetyl l-carnitine HPLC, green tea extract, banaba leaf extract, cayenne pepper and theobromine HPLC. When taken as three capsules, twice daily, the formula is supposed to promote weight-loss. You can take the pills with you, one positive.

The product, offered by NutraBio after 1996, leaves behind all synthetic ingredients, which is a nice choice. You can buy Thermofuel directly from the company or from third-party websites. We like that the supplement label is there for customers to see and you can reach a representative Monday to Friday, but read on…

Side Effects – What Do You Have to Worry About?

The first thing we noticed about Thermofuel ingredients was the potential for side effects. “Dieters are smarter now than ever before,” says our Research Editor. “They are on the lookout for safe, effective supplements. If a formula comes with risk, they’ll find another to try.”

According to the National Institutes of Health Office of Dietary Supplements, synephrine comes with risk of “chest pain, anxiety, increased heart rate and elevated blood pressure.” The chance of these side effects increases if the ingredient is taken with caffeine or other stimulants.

We also found mention of potential issues as stated by the Finnish Food Safety Authority. The office reports, “Denmark and Sweden have declared food supplements containing synephrine and caffeine in a combination to be unsafe to health.” Thermofuel contains both.

Scroll below for one of the best products we’ve seen in 2015.

Caffeine – Too Much of a Good Thing?

Thermofuel side effects don’t just stop with synephrine, it also contains caffeine. We like this stimulant as there’s some research showing increased energy among other benefits. The trouble is when you add too much because that can cause negative reactions that leave the dieter feeling worse for the wear. This supplement delivers 200 mg of caffeine per serving and the user takes it twice per day. This doesn’t count the amount added to the total from the green tea extract, which could add another 50 to 100 mg.

The Office of Disease Prevention and Health Promotion explains any caffeine intake “[greater than] 400 mg/day” is considered excessive. High amounts can cause “uneven heart rhythm, [increased] blood pressure, headaches, nervousness or dizziness,” warns the FDA. Other potential effects to take into consideration are dehydration and dependence.

Our research and experience shows a definite connection between simple issues, like side effects, and lesser chances of long-term success. If Thermofuel really does come with potential adverse reactions, the dieter may want to look around for a substitute.

The Science

There are studies showing caffeine promotes metabolic rate, so it is a good addition to any diet supplement worth trying, but we are worried about Thermofuel adding too much. According to a study from the Journal of Applied Behavior Analysis, “Caffeine is thought to be addicting, and prolonged and excessive use can lead to caffeinism, a condition that has serious behavioral and physiological side effects.” At DietSpotlight we look to science to give us the inside info about a product. In the case of Thermofuel, the scientific research tells us that we should be wary of any pill that packs in too much of any stimulant.

The Bottom Line

Thermofuel was quite the interesting supplement. We like that NutraBio Labs has an “A+” BBB rating and the company has been around for nearly 20 years, but we can’t recommend a product with strong potential for side effects. We’re also concerned that it is suggested the dieter continue for three months to see the best results. That’s far too long at that caffeine level.

If you’re ready to start down the path to weight-loss, we suggest a product that offers proven effects via clinically researched ingredients, with no reported side effects.

Among the best products we’ve reviewed in 2015 is one called Leptigen. The supplement contains four ingredients packed in a proprietary blend with clinical support showing it helps spark metabolism and boost fat loss. There is absolutely no talk of harmful side effects, but we did find dieters reporting seeing amazing results.

Also, the producers of Leptigen are confident enough in the formula to offer a special trial offer, not bad.

Learn More About Leptigen »

(Feel free to scroll below for our previously published full-length Thermofuel Review)

Previous Thermofuel Review (Updated February 6, 2014):

What You Should Know

Click Here To See Our Highest Rated Review

Thermofuel is a fat burning pill that is put out by the company NutraBio. NutraBio has been making supplements since 1996. It claims to have the highest and purest supplements available. NutraBio produces many other supplements for weight loss, weight gain, joint health, and sport and muscle.

Thermofuel uses what is known as the futile cycle. This refers to the natural ability of the body to burn fat without muscular activity.

List of Ingredients

Advantra Z, Green Tea Leaf Extract, Chromium Picolinate, Cayenne Pepper, White Willow Bark, Vitamin B6, Yerba Mate Leaf. Other ingredients include cinnamon bark, glucomannans, cordyceps, and ginger root.

Product Features

Advantra Z is the most active ingredient in Thermofuel. It is clinically proven to enhance metabolic rate without placing someone at risk of dangerous side effects. It is known to increase thermogenesis (the process by which vital nutrients are absorbed by the body from consumed foods and helps in maintaining weight loss), reduce weight, maintain lean muscle mass, and decrease your appetite. Green tea extract is the second most active ingredient in Thermofuel and it contains caffeine which assists in letting stored body fats loose so that they may be used for energy. Green tea also improves your metabolism and contains catechins. Catechins decrease fat absorption, suppress your appetite, and increases the release the fat. The third most active ingredient is chromium picolinate. This ingredient controls insulin levels, maintaining blood sugar levels, thereby, making it easier for the body to burn fat. Cayenne pepper (the fourth most active ingredient) studies seem to support the assertion that when it is taken, it increases the production of epinephrine and norepinephrine, thereby, decreasing appetite. Cayenne pepper is known to improve metabolic rate. White willow bark (the fifth most active ingredient) assists in pain relief. When it is combined with green tea extract and Advantra Z, it may increase the thermogenic process and help maintain lean muscle mass. Vitamin B6 (the sixth most active ingredient) assists in the breakdown of carbohydrates, fats, and proteins. The seventh most active ingredient is Yerba Mate. Yerba Mate helps you during exercise by breaking down carbohydrates so that you burn more calories.

At its official website, Thermofuel is fairly affordable. A 90-capsule bottle retails for $43.99. The price charged to you is $21.99, resulting in a savings of about 50%. A 500-capsule bottle is available for $59.99, resulting in a 69% savings. A 1000-capsule bottle is available for $99.99, producing a savings of 78%. One capsule should be taken three times daily.

See Our Featured Diet


  • Official website contains a couple before and after photos.
  • Claims to be the most comprehensive fat burner on the market.
  • Offers a 100% satisfaction guarantee.
  • Company has ten years of experience in the dieting industry.


  • Green tea and caffeine increases chances for jitters.
  • Lack of customer testimonials for people taking Thermofuel.
  • Does not emphasize the importance of regular exercise and healthy diet.
  • Does not claim to help you lose weight.


Thermofuel is put out a NutraBio, a company that has helped professional bodybuilders and everyday people to burn fat and increase muscle definition. NutraBio claims to not use any filler ingredients in its products. Thermofuel is affordable but does contain ingredients with known side effects and does not claim to help you lose weight.

GD Star Rating

One User Review About Thermofuel

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  • 1

    My mother in law is wanting to try this product but my concern is that she has not talked to her Dr about it. I have told her that she should speak to him before use because of the medication that she is taken.


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