Shopping for fat-loss supplements can be a bit confusing. After all, many of them have some of the same ingredients, so what makes one better or worse than the other? Also, some of them use the herbal versions of other compounds. Are those as good? Or are they even better? And just because one brand outsells the other, does that mean it's a truly superior product? Or does that supplement company just spend more on advertising and perhaps pay the sales clerk at the store a little something extra under the table for suggesting their brand? (Yep, it happens.)

So with all of the various "fat burners" out on the market, I decided it's about time to compare their efficacy and see which one is the best. Now when I say "efficacy," I'm talking about the degree of solid research that each ingredient has and how well it'll work in humans.

With that in mind, I'm going to assign each ingredient a score on a scale of 1 to 10 with 10 being the best. A high score means the ingredient has a significant amount of solid research behind it and a good reputation. A low score means that it has very little, if any, research supporting its efficacy and a less than good reputation for working in the real world. Let's get started. At the end of the article, I'll rate a number of formulations on the market and take into consideration their individual ingredients.

I'll warn you, though, there's a chance that one of our favorite formulations is, as they say in the supplement biz, ca-ca.

Alpha-Lipoic Acid

This substance has been shown in both human and animal trials to increase insulin sensitivity in skeletal-muscle tissue. This can improve glycogen storage and can help in terms of allowing more glucose to be shuttled into muscle cells as opposed to the extra glucose in the bloodstream being shuttled into fat cells. In other words, you can prevent some adipocyte (fat cell) hypertrophy to some extent even when you increase carb intake to a fair amount. Lastly, this substance is also a potent antioxidant.(3,4,5)

Rating: 7


In theory, aspirin could help to increase the efficacy of ephedrine and caffeine and that's why it's often included in many fat burners. But when researchers actually looked to see exactly how much aspirin contributed to the overall efficacy of ephedrine and caffeine, they found that it had little, if any, effect. (Despite this, many supplement makers are still including "A" in their ECA stacks.)

Now, normally, it wouldn't be a big deal if you included something that may or may not help ephedrine and caffeine much in terms of efficacy, but in this case, aspirin can be potentially harmful. It's been shown that as little as 10 to 75 mg can cause gastrointestinal bleeding in normal humans. This can be life threatening in some cases. Definitely not worth an added 1% in efficacy. (6-11) Also note that some companies use white willow bark, which is sort of an herbal aspirin.

Rating: 1


This compound has little research behind it. The only study I found was performed in vitro using rat fat cells. This compound was shown to enhance the mechanism of lipolysis but didn't itself increase lipolysis. (12)

Rating: 2


This amino acid has been included in a few formulations because of its textbook roles in fat metabolism. Essentially, it transports long-chain fatty acids into the mitchondria to be oxidized and it also modulates the metabolism of coenzyme-A.

So does this mean it'll increase fat oxidation? Not likely. Carnitine isn't something that would normally be depleted in the human body. However, if you're in a severely calorie-deficient state for a prolonged period of time and don't consume much meat, then you may, in theory, benefit. Even so, there isn't really any evidence supporting its use. (25)

Rating: 2


This plant is present in most formulations and it contains more than one ephedrine isomer. Ephedrine is great but when you evaluate the data behind each of the other isomers, you find that they each have a unique property. For instance, ephedrine itself is the best in terms of beta-2 agonism and nor-ephedrine is the best appetite suppressant. Overall, ephedra sinica, which contains four ephedra alkaloids, is certainly the most potent substance we have in terms of reducing fat.

Rating: 9.5


This is the direct precursor to the neurotransmitter serotonin and it works by simply elevating levels of this neurotransmitter. Why is this important? Well, when you diet, serotonin levels drop rather significantly and this is what causes carbohydrate cravings that lead to eating three boxes of cookies after working so hard to stay "strict" all week.

Because 5-HTP increases serotonin production, numberous studies have shown it to aid in weight loss and drastically reduce carb cravings, and thus carb intake. It's also been well documented that 5-HTP can elevate mood or relieve some depression in certain individuals.(22,23,24)

Rating: 9


This substance, in theory, should work since its ability to stimulate cAMP production (which increases lipolysis) has been well documented. However, does this mean it'll actually work in humans? It looks hopeful at this point and forskolin is getting a reputation for being a natural, non-suppressive thyroid booster.

Fellow contributor Doug Kalman wrote a great piece and reviewed the current literature supporting forskolin as a weight loss supplement.

Rating: 8

Ginger (Gingerols, Shogaols) and Red Pepper (Cayene, Capsaicin)

These compounds have been shown to increase energy expenditure and oxygen consumption via adrenal catecholamine secretion (mostly epinephrine) and there's actually some research in both humans and animals. The problem? Well, yes, an increase in energy expenditure is usually a good thing as long as what's being oxidized are lipids and not carbohydrates. When you increase carbohydrate oxidation, you essentially end up exhausting glycogen stores while preserving fat stores. Well, this is exactly what capsaicin has been shown to do! And ginger is nearly as potent as capsaicin in this regard. So, it's pointless to add these to any formulation. (13-17)

Rating: 0

Green Tea (Catechin-Polyphenols)

Green tea actually has a good amount of research in humans to support its efficacy. People used to think it was only effective because of its caffeine content, but researchers have found that the catechin-polyphenols contained within actually have an effect independent of caffeine.

One study found that green tea elevated energy expenditure whereas caffeine itself had no effect. Researchers believe that this is accomplished by the catechin-polyphenols' ability to inhibit the enzyme responsible for the degradation of norepinephrine (meaning that norephedrine's fat-burning effect lasts longer) and thus explains the increase in urinary norepinephrine excretion in humans. (18,19)

Rating: 7.5


This has been put in many fat burners as a replacement for caffeine, which is what's normally used in the ephedrine/caffeine stack. Since guarana contains caffeine, people think that it's just as good as plain old caffeine in terms of results. However, a while back some researchers compared caffeine to coffee, which contains caffeine just as guarana does. What they found was that even though the amount of caffeine used was the same, the coffee had no effect in terms of the parameters measured for lipolysis, whereas the caffeine alone did.

So does this mean that perhaps guarana isn't as effective as pharmaceutical-grade caffeine? Maybe. But I'm going to be safe in this case and only stick to those products which contain pure caffeine.

I think the reason certain companies use guarana is because it sounds more exotic than just plain old caffeine, not to mention the average person thinks "herbal" or "natural" means it's better for you. I guess that means snake venom and tobacco are too, huh? Skip the guarana and use caffeine.

Rating: 4


This biogenic amine has been added to many formulations in the past few years and at first was touted as an "ephedrine replacement." Well, as many people found out, it's far from that and isn't nearly as effective. Still, it's been shown to possess some beta-adrenergic activity, both at the beta 2 and beta-3 receptor. ("Beta-adrenergic," in really simplified terms, means, for the purposes of this article, that the compound in question increases heart rate and has an overall thermic, or heat producing effect. As such, the compound helps the body burn more fat.) The problem as I see it, is that it doesn't activate lipolysis (fat burning) very well and there's a lack of research in terms of safety. (1,2)

Rating: 3


This amino acid serves as the raw material for many important compounds that are associated with dieting. It's basically a precursor to the all-important metabolism controlling thyroid hormone T3, and a precursor to the "feel good" neurotransmitters epinephrine, norepinephrine, and dopamine. Neurotransmitter stimulation can help maintain optimal thyroid output during a strict diet. Not only that, but Tyrosine has been shown to increase the effectiveness of substances like ephedrine.

Rating: 6


This substance has been around for a few years and certainly has its place among effective lipolytic agents. An alpha-2 antagonist, it binds to alpha-2 receptors and essentially allows lipids to be mobilized from adipocytes that normally wouldn't be released very easily. Alpha-2 receptors are basically responsible for those "problem areas" of fat storage, like the obliques in men and lower body in women. Yohimbine could help target those areas. It has a good amount of research behind it, so it's not just a theoretical notion.(20,21)

Rating: 9.5

Rating the Formulations

Okay, so with that analysis of most of the individual ingredients, you can now rate just about any fat loss product. Now I'll go over a few formulations and give them an overall ranking on a scale of 1 to 10, 10 being best, 1 being worst.

Editors Note: Because there are a couple of supplement companies out there that like to slap frivolous lawsuits on anyone talking about the efficacy of their products, we're going to leave off most of the brand names and just focus on the formulations.

Product A

  • Citurs Aurantium – Standardized for 5 mg synephrine
  • Ma Huang – Standardized for 20 mg ephedrine
  • Guarana Extract – Standardized for 200 mg caffeine
  • White Willow Bark Extract – Standardized for 16 mg salicin
  • Acetyl L-carnitine
  • L-Tyrosine
  • Ginger Root
  • Vitamin B5

This product starts out okay, but then takes a turn for the worst. The ephedrine is a good start and the tyrosine is also warranted. The ginger root, salicin, guarana, and vitamin B5 aren't necessary. The synephrine shouldn't be included for reasons I mentioned previously.

The salicin certainly shouldn't be in there as it does more harm than good. The addition of acetyl l-carnitine won't help the efficacy of this product, either, so you're paying for an ingredient you don't need. Essentially, the only good ingredients are the ephedra and tyrosine.

I give this product an overall rating of 6.

Product B

  • L-phenylalanine
  • L-tyrosine
  • Ephedra Extract
  • Caffeine
  • Willow Bark Extract

Okay, here we have phenylalanine (another amino acid which can lead to increased norepinephrine levels) as well as tyrosine. We also have ephedra and this time, regular caffeine. The only problem I see is the inclusion of willow bark extract which contains salicin. It's not necessary and even potentially dangerous to include aspirin or aspirin-like compounds in the formulations.

I give this product a 5.

Product C

  • Guarana Extract
  • Ma Huang Extract
  • Citrus Aurantium (synephrine)
  • Green Tea Leaf Extract
  • Ginger Root
  • Cayene Fruit
  • Coleus Forskohlii (Forskolin)

This product is great except for three things: One is the inclusion of ginger root and cayene, which, as I stated earlier, may actually decrease glycogen stores while preserving fat stores. The other problems would be the inclusion of guarana instead of caffeine, plus it included synephrine, which I can't find much on in terms of safety.

I give it a 7.

Product D

  • Coleonol/Forskolin
  • Synephrine
  • Bergenin
  • Gingerols and Shogaols

This product only has one ingredient that's effective and that's the forskolin. The synephrine doesn't have much proof behind it, nor does the bergenin and as mentioned previously, the gingerols and shogaols may decrease glycogen stores and preserve fat stores.

I give it a 4.

Product E

  • Hydroxycitric acid
  • Guarana Extract
  • Ma Huang Extract
  • Salicin
  • L-Carnitine
  • Chromium Picolinate

This product has a few ingredients I didn't touch on, but don't worry, they aren't really even worth spending time on–just more label clutter that doesn't really do anything in terms of fat loss.

The effectiveness HCA is purely theoretical in terms of preventing lipogenesis via carbohydrate conversion to triglyceride. The guarana once again should be replaced with pure caffeine. The salicin does more harm than good. The carnitine isn't necessary and the chromium picolinate is worthless unless you're deficient.

I give it a rating of 5, and that's only because it contains ephedrine.

Product F

  • Green Tea Extract
  • Caffeine
  • Ephedra Alkaloids
  • Phenylalanine
  • Tyrosine
  • Taurine

This formulation is actually pretty good. It contains ingredients that are rather effective and follows my guidelines for an effective lipolytic agent.

I'd give this formulation a 7.5, but not any higher beause it's lacking 5-HTP and yohimbine.

Biotest MD6

  • Ephedra Sinica Extract
  • L-Tyrosine
  • Alpha Lipoic Acid
  • Caffeine
  • 5-hydroxy-L-tryptophan (5-HTP)
  • Yohimbine HCL

This, in my opinion, is the best of the "fat burners" on the market, and no, it's not because I'm writing this for T-mag! It contains every ingredient that I feel is effective with the exception of green tea. Still, it's the closest to perfect in my mind.

It takes care of thermogenesis, appetite, mood, neurotransmitter formation, and insulin sensitivity.

I give this formulation a 9.5 only because of the lack of green tea and because nothing in life is perfect, only near-perfect. Hey, there's always room for improvement!


Hopefully this will help you make a decision the next time you're scanning labels at your favorite supplement store or shopping online. After all, just as with training and diet, the more educated you are about supplements, the better you'll look at the beach!


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