The sports nutrition market is an interesting place for sure. It’s a hugely competitive market with countless numbers of products that claim to help you burn fat, build muscle, and boost your performance.
While there are certainly many supplements out there that actually do live up to their claims, many others are full of ineffective ingredients.
Do Fat Burners Actually Work?
Fat-loss supplements are probably the most saturated niche in the supplement industry.
Most every company has its own unique, “proprietary blend” of “magic” ingredients that are the secret to getting that shredded six pack you’ve always wanted.
Sadly, many of these supplements just give the user a short-lived burst of energy (likely from caffeine) but do little else to accelerate the fat-loss process.
Given this, it’s about time to construct an in-depth guide on some proven, research-backed supplement ingredients that actually have positive effects on metabolic rate and help individuals get rid of those pesky love handles.
The good thing about these ingredients is that almost all of them are incorporated into a fat loss supplement called BURN-XT.
Before we move on, bear in mind that the supplements discussed cause fat-loss by increasing metabolic rate, tissue oxidation, or both.
Therefore, if you take these supplements and overeat then you’ve essentially negated the purpose of taking them in the first place.
However, some people who are not looking to lose fat can still benefit from these supplements as it will give you the freedom increase food intake a bit since you’re burning more calories and oxidizing more fat throughout the day.
With that in mind, let’s move on to the main parts of this guide.
What Is Metabolism?
Before we get into the ingredients that boost the metabolic rate, it’s useful to have an understanding of what exactly metabolism is.
All living organisms are made up of the simplest living unit: the cell.
Within every cell, chemical reactions constantly occur that use up and also releasing energy in the process.
These reactions are divided into two categories: anabolic and catabolic. The former utilizes energy to build molecules while the latter gives off energy as they break down complex substrates (like glycogen).
At its simplest, metabolism is the sum of all of these physiological reactions within the cell that are necessary to sustain life.
Many variables, such as energy availability, affect how these reactions occur and when they take place; however, those variables extend beyond the scope of this guide.
Again, just know that metabolism is a highly intricate system of reactions in cells that sustain life, and there is an energy input and output from these processes.
Boosting the Metabolic Rate
With the summary of what metabolism is in mind, it should be rather intuitive that boosting metabolic rate is basically increasing the speed of how rapidly anabolic and catabolic reactions take place in cells. Therefore more nourishment will be needed to stay in a basal energy state.
In the case of losing fat, we actually want to avoid being in a positive or balanced energy status all the time since that would inhibit catabolic processes.
This is why health gurus often say that “calories in versus calories out” is ultimately what matters at the end of the day to determine whether you will lose fat or not, which for the most part is the truth (with a few finer points to consider).
Supplements Aren’t Magic
Before delving into what ingredients you should consider when looking for an effective fat-loss supplement, it is important to know that no supplements will “do the work for you” or make up for poor dietary habits and lack of exercise.
Therefore, the supplements analyzed herein should be used with a dedicated exercise and diet regimen, not as a replacement for those lifestyle choices.
For practicality, it is advised to first and foremost get your nutrition and training plan on track before investing in fat-burning supplements.
Now with this slight disclaimer out of the way, let’s take a look at some of the most effective fat-burning ingredients that you should consider when investing in a fat-loss supplement.
The rest of this guide will give a brief description of what each ingredient does physiologically, what dosage you should take, and when to take it.
The Best Fat Burning Supplement Ingredients
1. Acetyl-L-Carnitine (ALCAR)
Carnitine is a biochemical synthesized via the amino acids methionine and lysine. The biologically active form (L-carnitine) is required for the utilization and breakdown of fatty acids.
An insufficiency of carnitine ultimately results in impaired entry of fatty acids and disturbed lipid oxidation.
ALCAR is a derivative of L-carnitine that appears to be more bioavailable than pure L-carnitine. [1]
How it works:
ALCAR increases levels of L-carnitine, which goes on to increase the oxidation of fatty acids in the mitochondria of cells. It also appears that ALCAR decreases the consumption of glucose so as to utilize more fatty acids for energy, which is a favorable effect when looking to burn fat and retain muscle mass. [2]
How much to take:
ALCAR is most effective when taken in single doses of about 1g (up to 3g per day). Taking in excessive amounts of ALCAR is wasteful as most of it will be excreted through the urine to maintain nominal blood concentrations.
When to take:
Ideally, it would be best to take ALCAR about 30-60 minutes before exercising (with or without a meal); it has a relatively long half-life so if it’s a bit longer then that it’s okay. If taking more than one dose per day, split them apart by about 5-6 hours.
2. Caffeine
A staple to most any fat-burning stack is the stimulant drug caffeine. Caffeine is an organic substance found in coffee beans, cocoa, tea leaves, and other foods/plants.
How it works:
The ingestion of methylxanthines postpone the breakdown of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) via inhibition of phosphodiesterase (PDE) enzymes; thus caffeine is considered a PDE inhibitor. Since cAMP and cGMP are crucial messengers in cell signal transduction, the metabolic processes in the cell are sent into “overdrive” after the ingestion of PDE inhibitors.
Therefore, the elevated metabolic rate would be conducive to helping burn more calories. This elevation in burned calories can further be increased by caffeine’s promotion of catecholamine activity. [3]
Based on the research, caffeine appears to complement both aerobic and anaerobic exercise, as well as lower the rate of perceived exertion (RPE). [4,5]
Essentially, after taking caffeine, you generally have an increased athletic performance capacity.
Thus you can work harder and longer than those who workout without caffeine use beforehand; this, in turn, would likely increase the calories and fat burned from exercise.
How much to take:
Dosages for caffeine vary by individual. It is generally recommended to take 1-3mg per kg of body weight at a time. [6] Remember, 2.2lb is equal to 1kg. If you’re a 180lb (81kg) person, your dose range will land between 80 and 240mg. Do not go too crazy with caffeine dosing since there isn’t much benefit to extra amounts and it can, in fact, be toxic at high enough doses (>5g). Be safe and methodical with caffeine; it is a drug, so treat it as such.
When to take:
As a starting point, try taking caffeine on an empty stomach about an hour before training. If you prefer to take caffeine with a meal, give yourself a bit more time before hitting the gym. If you find your performance in the gym is indeed increased after using caffeine, then there is little reason to alter your approach. On the contrary, if you notice no change or a decrease in performance, you will either want to adjust your dose or change the dose timing.
3. Yohimbine
Yohimbine is a stimulant compound derived from the plant species Pausinystalia Yohimbe. It is an antagonist of alpha-2 adrenergic and acts as a monoamine oxidase inhibitor (MAOI).
How it works:
Research seems to suggest that, when taken pre-exercise, yohimbine enhances lipolytic (fat releasing) activity via blockade of alpha-2 adrenergic receptors in adipocytes and stimulation of catecholamine release. [6,8] It is further purported that yohimbine works most optimally in the absence of insulin (or preferably in a fasted state). [7]
How much to take:
As with caffeine, yohimbine intake needs to be carefully monitored so as not to overdo things. As with other supplements, yohimbine dosage will vary by body size, and taking from scientific literature, it appears that about 0.1-0.3mg per kg of body weight at a time is a sufficient dose for fat loss. As well, you may take up to 3 doses per day if necessary.
When to take:
It is preferable to take yohimbine about 20-30 minutes pre-exercise (especially cardiovascular activity) and on an empty stomach.
4. Synephrine
Synephrine is another stimulant compound extracted primarily from citrus aurantium tree leaves. It can also be found in trace quantities of oranges and orange food products. It is structurally similar to the neurotransmitters epinephrine and norepinephrine.
How it works:
It appears that synephrine works primarily through stimulation of beta-adrenergic receptors, thereby increasing concentrations of catecholamines in the blood which in turn activate lipolysis in adipocytes. [9]
How much to take:
Synephrine should be taken in quantities quite similar to that of yohimbine. As above, this equates to about 0.1-0.3mg per kg of body weight per dose.
When to take:
Since synephrine appears to enhance lipolysis primarily by agonism of beta-adrenergic receptors, this should preferably be taken before exercising (say 30-60 minutes pre-workout).
5. Capsaicin
Capsaicinoids are the compounds found in peppers that give them spice. Research has supported the finding that capsaicin acts to increase metabolic expenditure. [10] The measurement of capsaicin content in certain peppers is given as Scollville thermal units.
However, the drawback to eating large amounts of hot peppers to reach nominal doses of capsaicinoids is impractical due to gastric irritation and other digestive maladies.
How it works:
Research supports that the mechanism for increased metabolic expenditure after ingestion of capsaicin is based on beta-adrenergic stimulation. [10] It is suggested that the increase in energy expenditure and decrease in respiratory quotient positively affect fat oxidation. [11]
How much to take:
In the Janssens et. al study, 2.56mg of capsaicin were provided with each meal. [8] It is likely that a nominal dose ranges between 2-3mg at a time, and may be taken up to 3 times per day.
When to take:
It is generally preferred to take capsaicin with meals since it may cause gastric irritation on an empty stomach. If you can tolerate otherwise than feel free to dose it at other times.
6. Green Tea Extract
Green tea extract has become a common ingredient in many fat-burning products, mainly due to its ability to raise the calories used during the day.
The primary constituent in green tea leaves responsible for this metabolic effect is the antioxidant epigallocatechin gallate (EGCG).
How it works:
Epigallocatechin gallate acts as an inhibitor of the enzyme catechol-O-methyl transferase, which serves to breakdown catecholamines. Therefore, ingestion of EGCG enhances the activity of neurotransmitters like dopamine and epinephrine, which positively effects fat burning. [12] It also an anti-carcinogenic agent and has potent antioxidant effects. [13]
How much to take:
This will depend on the concentration of EGCG provided by the green tea extract you use. The positive metabolic effects observed in research are achieved with a dose of about 150-250mg of EGCG per day. [14]
When to take:
Preferably take green tea extract/EGCG about 30-60 minutes before you work out since it slows the breakdown of catecholamines.
7. Pyrroloquinoline Quinone
PQQ is an organic compound contained in bacteria and is primarily retrieved from fermented soybeans. Interestingly enough, it appears that PQQ acts to create new mitochondria in cells, a process known as mitochondrial biogenesis. [15]
The drawback to PQQ at this point is that it is rather expensive and hard to source. However, as research on PQQ increases, it is likely more companies will start incorporating it into their fat-loss supplements.
How it works:
PQQ acts as a cellular messenger mimicking some of the most fundamental physiological adaptations of exercise, ultimately increasing the body’s natural production of the hormone irisin. In humans, irisin release can be considered one of the most positive benefits of physical activity, as circulating irisin levels are negatively correlated with age, insulin, cholesterol, and adiponectin and positively correlated with fat-free mass and ghrelin. [16] Also, as mentioned before, PQQ serves to increase mitochondrial biogenesis, a favorable adaptation that increases metabolic rate, much the same way high-intensity interval training does.
How much to take:
Placebo-controlled safety studies in humans show the consumption of PQQ at 20mg and 60mg per day is effective and safe. As noted above, PQQ is somewhat costly if you want to take it in nominal doses.
When to take:
Timing of PQQ is not too important since its effects are somewhat latent and develop after regular use has been established. Just be consistent and use it every day if you do take it.
8. Raspberry Ketone
Raspberry ketone is the major aromatic compound of red raspberries (Rubus idaeus).
It’s actually quite similar in chemical structure to synephrine and capsaicin discussed earlier. Therefore, it’s suggested that RK is a worthwhile ingredient for fat loss.
How it works:
As with other catecholamine releasers, RK has been shown to significantly increase norepinephrine-induced lipolysis in white adipose tissue. [17] Moreover, RK has been shown to inhibit small intestinal absorption of dietary fat by suppression of pancreatic lipase (an enzyme secreted to breakdown fatty acids).
How much to take:
Typical doses for RK range from 200-400mg per day (divided into at least two doses).
When to take:
It is suggested to take raspberry ketone twice per day, with one of those servings preferably 30-60 minutes before working out.
9. Hesperidin
Hesperidin belongs to a class of organic compounds known as flavanones (a form of glycosylated flavonoids) and is primarily found in citrus fruits such as oranges, lemons, and limes.
Along with many antioxidative properties, hesperidin appears to act synergistically with naringin (to be discussed next) to regulate carbohydrate metabolism and subsequently decrease serum insulin. [18]
How it works:
As noted above, hesperidin acts by attenuating oxidative stress and hyperglycemia. Moreover, hesperidin has been shown to reduce adipose tissue and regulate mRNA expression of lipid metabolism-related proteins. [19] Synergistically, taking naringin and caffeine along with hesperidin appears to further augment lipolysis via PDE inhibition. [20]
How much to take:
It is advised to take around 500mg of hesperidin per day, preferably with food.
When to take:
Similar to naringin, synephrine, and caffeine, it’s beneficial to take hesperidin with food.
10. Naringin
Naringin is another flavanone that is found in citrus fruits (especially grapefruit) and has a variety of antioxidative and metabolic effects in humans.
It also inhibits several cytochrome p450 enzymes, so care should be taken if using naringin and hesperidin while taking drugs that act on those enzymes.
How it works:
Similarly to hesperidin, naringin appears to possess lipid-lowering and carbohydrate-regulating properties. Studies corroborate that ingestion of naringin ameliorates insulin resistance, hyperglycemia, and dyslipidemia. [18,21,22] Moreover, naringin acts in concert with other PDE inhibitors such as caffeine and synephrine to prolong cAMP elevation, which in turn, is favorable for fat loss.
How much to take:
Despite having few human studies to date, it appears that a nominal dose of naringin is around 500-1000mg taken orally.
When to take:
As with hesperidin, take naringin with a meal to maximize benefits.
11. Forskolin
Forskolin belongs to a class of organic compounds known as terpenes.
It is derived from the Indian plant Coleus forskohlii. It has been found that forskolin acts to increase intracellular cAMP levels and is important for cell signaling.
How it works:
Forskolin usage increases intracellular levels of cAMP primarily by elevating activity the adenyl cyclase enzyme. Moreover, it also has been shown to raise lipolysis in cells without a concomitant increase in cAMP. [23] Forskolin may also act on the endocrine system to increase testosterone levels, which has ramifications on lean body mass. [24]
How much to take:
Human studies show that about 2 doses of 250mg of Coleus forskohlii extract (standardized to 10% forskolin) were enough to produce significant changes in fat-free body mass and cAMP levels.
When to take:
Since some of the benefits of forskolin are mediated by the endocrine system, administration timing doesn’t appear to be too important. However, it is best to split the dose into two times per day and take one of those doses about an hour before exercising.
Bringing It All Together
Hopefully by this point you are up-to-speed on these highly effective fat-burning ingredients.
If an ingredient that you commonly see in some fat-burning supplements is omitted from this guide than it is likely not listed for a reason. It could lack scientific evidence, be too costly, or simply not impact the fat-loss process.
Do note that “appetite-suppressants” are not included in this guide as they’re technically in a different category of supplements.
Don’t forget, use of a fat-burner supplement is only going to be effective when used in conjunction with a proper exercise and diet plan. That being said, it will benefit you to invest in a top fat burner like Burn-XT while trying to shed body-fat as it can greatly accelerate the process. Don’t shortchange your physique; you only get one body in this life.
References:
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- Stephens, F. B., Constantin‐Teodosiu, D., & Greenhaff, P. L. (2007). New insights concerning the role of carnitine in the regulation of fuel metabolism in skeletal muscle. The Journal of Physiology, 581(2), 431-444.
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- Galitzky, J., Taouis, M., Berlan, M., Riviere, D., Garrigues, M., & Lafontan, M. (1988). α2‐Antagonist compounds and lipid mobilization: evidence for a lipid mobilizing effect of oral yohimbine in healthy male volunteers. European journal of clinical investigation, 18(6), 587-594.
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- Janssens, P. L., Hursel, R., Martens, E. A., & Westerterp-Plantenga, M. S. (2013). Acute effects of capsaicin on energy expenditure and fat oxidation in negative energy balance. PloS one, 8(7), e67786.
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