Review: Gaspari Nutrition's Phenorex Fat Burner -

Review: Gaspari Nutrition’s Phenorex Fat Burner

Gaspari’s Phenorex fat burner is probably best described as a slightly modified version of their Spirodex product, which Gaspari claims suppresses appetite and boosts energy.

Phenorex is described as a “Intense Thermogenic Bio-Amine”, which as far as I can figure means very little, other than the obvious; it’s a thermogenic that contains biogenic amines. Big deal. So are most of the fat burners on the market today.

That said, Gaspari products usually warrant a closer look for the simple matter that they do put a little more thought into their offerings than many of their competitors.

So let’s talk about Phenorex.

As it has done with Spirodex, Gaspari has dispensed with the typical product presentation and has opted for plain, official-looking packaging. This makes Phenorex look more like it belongs behind the shelf at your local pharmacy than bundled in with Slim Quick, Hydroxycut and Lipozene on the weight loss counter of your local Wal-Mart.

But does presentation make the product? I’ll bet you already know the answer to that one, but let’s take a look at the ingredient profile anyway.

What’s in Phenorex?

Carnipure (l-carnitine l-tartrate):Various forms of carnitine have been used in fat burners for ages, despite contradictory study results and effective doses vastly exceeding that which could be jammed into a half dozen capsules (any positive studies have been achieved with multi-gram doses).

With only 335 mg of ingredient in the entire Phenorex complex, the carnitine element of this formula can only be considered as “label dressing.”

Oxytropis falcata extract: Misspelled in the Gaspari advertising as “Oxytropis falcate” (also known as “locoweed”), this is a toxic Chinese plant of the bean / pea / legume family that has been used in ancient Chinese medicine for centuries as an anti-inflammatory—there is some evidence to support its usage.

It’s also a rich source of numerous flavonoids including kaempferol, quercetin and chrysin.

According to Gaspari, this element of the formula is standardized for “biogenic amines” (in “cognition supplements” like this one, this often refers to neurotransmitters), although they do not reveal which one(s) or to what potency they are standardized.

That turns out to be a problem, because discovering which “biogenic amines” O. falcata might be standardized for is difficult, as the English studies I located discussed its flavanoid content solely, while other studies discussing its constituents were published in Chinese. However, this review article indicates O. falcata is a source of several substituted phenylethylamines.

Once again, it’s impossible to confirm exactly which—if any—phenylethylamine (PEA) derivatives are included here (phenylethylamine is the amphetamine-related chemical commonly found in chocolate. It is rapidly metabolized by the enzyme monamine oxidase (MAO), which makes oral supplementation pointless unless it’s accompanied by an MAOI (monamine oxidase inhibitor) or two).

Nonetheless, PEA is an ingredient Gaspari likes to “play” with; both their CytoLean (now discontinued) and CytoLean V2 fat burners contain it and a series of MAOIs. This isn’t necessarily a good thing. As Elissa noted in a correspondence with me about Spirodex…

“The family of phenylethylamine-derivatives contains some pretty scary members. And there appears to be very little information available on either the pharmacology or toxicity of these derivatives. I feel it’s irresponsible for Gaspari to be playing “guessing games” with its customers over the ingredients in this product.”

Caffeine: No surprise to find caffeine in this product. It’s a common addition to most thermogenics on the market; it has demonstrated—albeit mild—effects on the metabolism (see Am J Clin Nutr. 1989 Jan;49(1):44-50, Am J Clin Nutr. 1980 May;33(5):989-97), it provides a “boost” of much-needed energy, and it’s an ingredient consumers can “feel” (which often leads to the perception that a product is “working”).

Advantra Z® Citrus aurantium extract: Advantra Z is a patented form of citrus aurantium, which is usually standardized for synephrine, a compound which has failed to demonstrate any significant weight loss effects, despite once being thought to be a credible alternative to ephedra. However, according to the Advantra Z patent abstract, it could also be standardized for 4 other “amines” (hordenine, octopamine, tyramine and N-methyltyramine) common to citrus aurantium.

In this formula, Advantra Z only makes sense if it is included as a source of hordenine, a highly selective substrate for MAO-B. Otherwise, the PEA derivatives extracted from Oxytropis falcata will be quickly metabolized by monamine oxidase. Gaspari has been using PEA in their thermogenics for some time now, and are well aware of the need of MAOIs to prevent rapid metabolizing. Hordenine is also included in the Spirodex fat burner, which contains the identical Oxytropis falcata extract, so it’s a logical assumption.

Paullinia cupana extract (standardized for purine content): Two thumbs down to Gaspari for disguising this common ingredient, guarana, and its purine content, most likely caffeine, with unnecessarily complicated nomenclature.

3,5′ Diiodothyronine and 3,3′ Diiodothyronine:Also present in their Mitotropin product, these are metabolites of the T3 thyroid hormone. Theoretically, supplementation with thyroid hormone derivatives can raise the levels of T3 itself, increasing the metabolic rate and calorie burn.

How effective are these compounds at doing so? Well, they’re mentioned along with a series of other thyroid hormone precursors in this study, where the authors state…

“Most of these compounds have interesting properties: counteracting lipid accumulation, reducing cholesterol level, and increasing lipid metabolism without cardiotoxic effects. Hopefully, further studies on basic mechanisms of such compounds will be harbingers of more knowledge on the metabolic effects of TH derivatives and on their possible clinical application.”

When conferring with Elissa about this, she informed me of an older study performed by the same research group that indicates some mitochondrial uncoupling may be part of the thermogenic effects.

One thing that isn’t discussed is the possible disruption of natural thyroid production. The aforementioned study references this possibility in its conclusion…

“… the results reported here do not exclude deleterious effects of T2 on a longer time scale as well as do not show that T2 acts in the same way in humans.”

John Berardi, writing on behalf of BioTest’s T2 fat burner (now discontinued, likely as a result of the growing disapproval of the FDA) dismisses this possibility, but admits that such effects are likely dose-dependent.

And of course, we know nothing about the dose in this product, so it is a possible issue.

And that wraps up the ingredient profile of Phenorex.

It’s hard to know what Gaspari was thinking when they created this product, or even why they created it in the first place (or continue to market it) given the existence of Spirodex.

It’s a “head scratcher” for sure.

From my perspective at least, there’s no major improvement with this formula. Arguably, the thyroid hormone metabolites may add some value, but you have to balance that benefit with the possibility of the disruption of natural thyroid production.

On the other hand, it’s possible that Phenorex—given that it is missing both the Chinese tea and dimethylamylamine present in Spirodex—delivers similar results without getting you wired out of your mind.

Maybe that was the motivation behind its creation?

Who knows?

Regardless, as with Spirodex, we’re a little hesitant to recommend Phenorex because of the Oxytropis falcata extract. As addressed earlier, we don’t know if and or which phenylethylamine derivative(s) it is standardized for, and that’s a problem, as there is very little information available on either the pharmacology or toxicity of these derivatives.

In other words, there’s a potential for risk here, and it’s irresponsible of Gaspari not to be more forthright with its customers about the true nature of all Phenorex’s constituents.

For that reason, this is not a Gaspari offering we can heartily recommend.

Author: Paul

Paul Crane is the founder of His passions include supplements, working out, motorcycles, guitars... and of course, his German Shepherd dogs.

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