iForce Nutrition Thermoxyn Review

Thermoxyn is iForce Nutrition’s most recent fat-burner which contains a wide variety of potentially effective weight-loss ingredients, both stimulant and non-stimulant…

iForce Nutrition Thermoxyn



Caffeine triggers the release of Catecholamines (i.e. Noradrenaline, Adrenaline, Dopamine) which, in addition to enhancing focus and alertness, are inherently pro-lipolytic. Although this mechanism can certainly burn fat in the short-term, prolonged Caffeine consumption (by itself) generally results in tolerance build-up so the effects become less potent over time. This was demonstrated in a 1992 study in which 24 weeks of Caffeine intake (200mg/day) failed to induce weight-loss in humans.

However, Caffeine’s effect on fat-loss can be amplified or extended by other stimulants such as Tyramine and Synephrine (both found in the Thermoxyn formula), so in the context of Thermoxyn it may contribute to overall weight-loss.


A 1998 study from “Phytochemistry” seeking to identify the chemical constituents of Acacia rigidula found various adrenergic amines such as Phenethylamine, Tyramine, N-Methyltyramine, and N-methylphenethylamine, all of which are used separately throughout various weight-loss supplements. What these compounds have in common is that they can all stimulate or potentiate the release of catecholamines such as Noradrenaline, which directly activates beta-receptors and induces lipolysis. So, while the mechanism by which Acacia rigidula can burn fat is certainly a solid one, the degree of efficacy in the context of Thermoxyn is somewhat unclear, since we don’t know the concentration of these compounds.


Citrus Aurantium, also known as Bitter Orange, is generally standardized for Synephrine, but also contains several other alkaloids including N-Methyl-Tyramine, Hordenine, Octopamine, and Tyramine. Though all of these compounds have certain mechanisms by which they can induce lipolysis and ultimately contribute to weight-loss, Synephrine is the most established (and also happens to be the most abundant).

A 2011 study, published in the “International Journal of Medicinal Sciences”, found that supplementation of 50mg Syneprhine increased the metabolic rate in human subjects without affecting blood pressure or heart rate. Similarly to Ephedrine, Synephrine is a beta-receptor agonist and an alpha-receptor antagonist, the net effect of which is an increase in lipolysis.

Synephrine certainly has a place in the Thermoxyn formula, as it can activate beta-receptors which, when stimulated by the Noradrenaline (released by Caffeine), can drastically increase lipolysis (fat-breakdown). When it comes to beta-agonists, the more exercise the better, since they do not inherently “burn fat”, but instead release fatty acids in to the blood stream to be burned during exercise.


Rauwolfia Serpentina is generally standardized for Rauwolscine (also known as alpha-yohimbine) which is chemically related to Yohimbine and can fulfill basically the same function in the context of a fat-burner. Like Yohimbine, Rauwolscine is an Alpha Receptor Antagonist, meaning it blocks the receptors responsible for blocking lipolysis. By blocking these receptors, Rauwolscine is able to potentiate the effects of other stimulant fat-burners and allow more fat-burning than would normally occur from exercise alone. However, since Rauwolscine generally appears alongside Yohimbine, it hasn’t been studied much in isolation, and an optimal (effective) dose has not yet been established. Combined with the other stimulants (Synephrine, Caffeine, etc.) in Thermoxyn, Rauwolfia Serpentina may very well contribute to noticeable weight-loss.


Lemon Verbena is a South American plant, the leaves of which are commonly dried and made into an herbal tea. However, aside from a pleasant lemony aroma, Lemon Verbena contains a number of anti-oxidants with a variety of health implications. In the context of Thermoxyn, Lemon Verbena appears to be intended to aid in exercise recovery and preserve muscle. A 2011 study, published in the “European Journal of Applied Physiology” found that Lemon Verbena was able to reduce exercise-induced muscle damage in healthy human subjects, while not interfering with the positive adaptations from exercise.


Despite the popularity of Raspberry Ketone, it has never actually demonstrated any efficacy for weight-loss in actual humans and, even in rat studies, has produced lackluster results using massive concentrations.

A 2010 in vitro study found that treatment with Raspberry Ketone increased fatty acid oxidation and lipolysis in adipocytes (fat cells). However, the amount/concentration of RK used in this study is beyond what could practically be consumed in oral supplement form.

A 2005 study, seeking to determine the weight loss effects of raspberry ketone on rats fed a high fat diet, noted dose dependent anti-obesity effects using doses of .5-4 grams/kg. This would roughly correspond to a 150lb person consuming 34-130 grams daily, a highly impractical dose.

In a 2012 study, similar effects were observed in rats, though this time with a focus on fat accumulation in the liver resulting from a high fat diet. The only human study that exists grouped Raspberry Ketone in with several other popular weight-loss ingredients so the effects cannot be attributed to raspberry ketones alone.

On a molecular level, Raspberry Ketone certainly demonstrates anti-obesity effects, but the doses used to achieve these effects are far more than what the average human could practically consume. There are other substances with much more pronounced fat-burning capabilities than raspberry ketone when compared by weight.


Garcinia Cambogia contains a compound called Hydroxycitric Acid (HCA), which is alleged to reduce body weight via inhibition of ATP Citrate Lysase, an enzyme required for the synthesis of fatty acids from carbohydrates (de novo lipogenisis). Theoretically speaking, blocking this enzyme would stop excess carbhydrates from being stored as fat. While inhibition of ATP Citrate Lysase has resulted in weight-loss in rodents, the implications for humans are less promising, because de novo lipogenesis occurs less in humans than rodents. Garcinia Cambogia has produced mixed results in humans.

A 1998 placebo controlled study found that 1500mg HCA daily failed to reduce bodyweight to a significantly greater degree than the placebo group.

A 2000 study, published in “Physiology & Behavior”, found that Garcinia Cambogia (1200mg HCA daily) significantly reduced bodyweight over a 12 week period compared to the placebo group.

However, a 2011 study found that 10 weeks of supplementation with 2 grams Garcinia Cambogia Extract (60% HCA) failed to reduce weight in overweight subjects, compared to placebo group.

So out of the human studies, 2 have failed and 1 has demonstrated efficacy using the same dose as one of the failed studies. Clearly these results are difficult to interpret, and there are no valid explanations for this discrepancy at this time.

Because of the popularity Garcinia Cambogia has gained in recent years as a potential weight-loss agent, several reviews have been done which have sought to determine its efficacy based on the evidence. Every review (and there have been at least four) has concluded that, while Garcinia Cambogia may be effective in rodents, this effect does not carry over to humans. While we aren’t so quick to dismiss Garcinia Cambogia, we are inclined to agree that, when looking at all the research, it doesn’t appear to be very effective in humans.

Thermoxyn contains an undisclosed amount of Garcinia Cambogia standardized to 50% HCA, meaning there would need to be over 2 grams to be in-line with the only positive human study. Given a proprietary blend of 1.4 grams, it is possible that at multiple doses, there is a pretty high dose of HCA. That being said, a high dose doesn’t mean an effective dose, given the conflicting research.


Green Coffee Extract (GCE) is similar to Garcinia Cambogia in terms of mechanism of action, but it holds much more promise. GCE contains Chlorogenic Acid, which is the primary bioactive compound responsible for the weight-loss achieved in several studies.

A 2010 study from “Food and Chemical Toxicology” found multiple anti-obesity effects of Chlorogenic Acid administered to mice including increase beta-oxidations (fat-burning). While this increase in fat-burning may have been partially responsible for the significant weight-loss noted in rodents, Chlorogenic Acid has an alternative mechanism of action that applied for to humans: Inhibition of carbohydrate absorption.

A 2007 study, published in the “Journal of International Medical Research”, found that 12 weeks of Green Coffee (450-500mg Clorogenic Acid) supplementation resulted in a reduction (6.9%) in glucose absorption in healthy volunteers. Researchers also noted average weight loss of 5.4 kg (almost 12 lbs) over the duration of the study in the group receiving the Green Coffee Extract.

A 2006 study, this time using a smaller dose of Green Coffee Extract (yielding 140mg Chlorogenic Acid), found no such weight-loss benefit over a 12 week period. The obvious difference between these two studies is that the dose of the first (positive) study was about 3 times the dose used in the second (negative) study.

A 2012 study found that adults who consumed GCE (containing about 315mg Chlorogenic Acid) daily lost an average of 8kg with the average reduction in body fat being about 4%.

Though GCE has shown mixed results in various studies, clear efficacy has been demonstrated at high enough doses (at least 300mg Chlorogenic Acid). Although the exact dose of Green Coffee Extract present in Thermoxyn is undisclosed, it is possible that at multiple doses, there is enough Chlorogenic Acid to convey some meaningful weight-loss benefits.


The primary active compound found in Olive Leaf Extract is Oleuropein, a potent phenol responsible for the extracts adrenergic effects.

A 2007 study from “The Journal of Nutritional Biochemistry” demonstrated increased Noradrenaline and Adrenaline levels in rats following injection of Olive Leaf extract.

Similar findings were noted in a 2013 study published from “The Journal of Nutritional Biochemistry” in which rats fed a diet high in Oleuropein experienced significantly increased Noradrenaline levels (measured in urine), though it’s worth mentioning that this was not accompanied by the usual decrease in weight.

In fact, Oleuropein may actually down-regulate beta-adrenergic receptors, as evidenced in a 2012 study from “The American Journal of Clinical Nutrition” (although this was in Endothelial cells, not fat-cells). Ultimately, while Oleuropein may certainly induce Noradrenaline release, thereby increasing perceived energy and focus, the fat-burning implications for humans remain unclear.


With the exception of Raspberry Ketone and Garcinia Cambogia, every ingredient in the Thermoxyn formula can induce weight-loss. Though mostly stimulant-based, the addition of Green Coffee Extract offers a non-adrenergic mechanism of action, thereby making Thermoxyn a multiple-mechanism fat-burner. Unfortunately, due to a lack of label transparency, we’re left to do a bit of guess work but, given an overall weight of 1.4g, there is no reason why a multiple dose regimen cannot deliver effective doses of all key ingredients. Since Thermoxyn contains several stimulants, we’d recommend starting with one serving and working your way up, but ultimately, this is the type of formula you’ll want to consume multiple doses of to derive the full benefits. At a little over 50 cents per serving, Thermoxyn is more or less appropriately priced so consuming multiple daily doses is actually a feasibly option.

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