Sports supplementation is a vast market with countless numbers of products that claim to help you burn fat, build muscle, and achieve your performance goals. While there are certainly a number of supplements out there that actually do live up to their claims, some of them are as bunk as sugar pills.
One of the most flooded niches in the supplement world is the fat-burning category. It seems like every company has their own unique, patented blend of magic ingredients that are the secret to get that shredded six pack you’ve always wanted. Ultimately, many of these supplements just give the user a short-lived burst of energy (likely from caffeine) but do little else to assist the fat loss process.
Therefore I found it prudent to construct a brief guide on some proven, research-backed supplement ingredients/compounds that actually have some positive effects on metabolic rate and help individuals trim off some fat. The good thing about these ingredients is that they are readily available from a variety a supplement companies and won’t break the bank. I will provide some specific products to consider from the Muscle & Strength store towards the end of this guide.
Lastly, bear in mind that these supplements assist the fat loss process due to the fact that they increase metabolic rate. This means that if you take these supplements and still overeat (based on your caloric expenditure) that you’ve essentially negated the purpose of taking these supplements 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 throughout the day. With that in mind, let’s move on to the meat and potatoes of this guide.
Metabolism—what is it exactly?
Before we get into the ingredients/compounds that boost metabolic rate it’s useful to have a rudimentary grasp of what exactly metabolism is. In a nutshell, all living organisms are made up of the simplest living unit—the cell.
Within these cells chemical reactions are constantly occurring and using and releasing energy in the process. These reactions are divided into two categories, those being anabolic and catabolic; the former use energy to build molecules while the latter give off energy as they break down complex substrates.
So essentially, metabolism is the sum of all of these physiological reactions within the cell that are necessary to sustain life. Many variables, such as hormone signaling and energy status, effect 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 inherent energy input & output from these processes (thus the need for nourishment).
Boosting metabolic rate
With the truncated summary of what metabolism is in mind, it should be rather intuitive that boosting metabolic rate is essentially increasing the speed of how rapidly anabolic/catabolic reactions take place in cells and therefore more nourishment will be needed to stay in a balanced energy state. In the case of losing fat, we actually don’t want to be in a positive or balanced energy status all the time since that would inhibit catabolic processes such as the breakdown of fat in adipose tissue, which take place when the cell is a negative energy state (which makes sense since catabolic reactions provide energy for the cell).
This is often why people will tell say that “calories in versus calories out” is ultimately what matters at the end of the day to determine whether you will lose fat, which for the most part is the reality (with a few exceptions).
Supplements that boost metabolic rate
So now with all the metabolism basics out of the way we can get to the matter at hand of which supplement ingredients/compounds to consider for boosting metabolic rate. The supplements covered in this guide are what I would consider to be the best supplemental options to naturally elevate metabolic rate.
The key word there is “naturally” since there are a handful of pharmaceuticals that can significantly elevate metabolic rate, but they can be habit-forming and unsafe when used improperly so they will not be considered here. I don’t see the use in sacrificing overall health to achieve a certain look, but that’s another topic in and of its self. Now, onto the good stuff!
You know that spicy kick in your mouth after eating some hot peppers? Well that’s the heat coming from capsacinoids—compounds found in peppers that give them spice/heat. Literature has supported the finding that capsaicin acts to increase metabolic expenditure.  The measurement of capsaicin content in certain peppers is given as Scollville thermal units. However, eating large amounts of hot peppers to reach nominal doses of capsacinoids is impractical due to gastric irritation and other digestive qualms.
Research supports that the mechanism for increased metabolic expenditure after ingestion of capsaicin is based on beta-adrenergic stimulation.  It is suggested that this increase in energy expenditure and concomitant decrease in respiratory quotient positively affect fat oxidation. 
Dosing—2.56mg of capsaicin were provided with each meal in the Janssens et. al study cited herein.  It is likely that a nominal dose ranges between 2-3mg at a time, and may be taken up to 3 times per day. It is generally preferred to take capsaicin with meals since it may cause gastric irritation on an empty stomach; if you can tolerate it otherwise than feel free to dose it at other times.
Epigallocatechin gallate (EGCG/Green tea extract)
Green tea extract has become a common ingredient in many fat-burning products due to its metabolic boosting properties. The primary moiety in green tea leaves responsible for this metabolic effect is the antioxidant epigallocathechin gallate (EGCG).
EGCG 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 metabolic rate.  As an added bonus, EGCG is also an anti-carcinogenic agent and has potent antioxidant effects. 
Dosing—The positive metabolic effects observed in the literature are achieved with a dose of about 150-250mg of EGCG per day. Therefore, the amount of green tea extract you need to supplement with will depend on the EGCG concentration of the product you use. Try and take green tea extract/EGCG about 30-60 minutes before you work out since it slows breakdown of catecholamines.
Caffeine is the most consumed stimulant drug in the world, obtained primarily from coffee beans. Caffeine is the only central nervous system (CNS) stimulant compound in this guide so it is recommended to tread with caution and consider cycling your use of it.
Caffeine works via inhibition of phosphodiesterase enzymes which prevents the breakdown of cyclic guanosine monophosphate (cGMP) and cyclic adenosine monophosphate (cAMP), two important chemical messengers that regulate signal transduction in cells. Therefore, ingesting caffeine will acutely increase metabolic rate and also appears to effect substrate utilization, especially fatty acid oxidation. [6,7]
Dosing—Caffeine is the trickiest of the compounds cited in this guide to use since it’s a stimulant. Research seems to suggest that 1-3mg per kg of lean body mass is a nominal dose for healthy individuals. As far as when you take it, just be sure not to ingest it prior to sleeping as you will likely have issues with insomnia. Also consider cycling your use of caffeine to prevent tolerance buildup; for more on this topic read here.
Pyrolloquinoline quinone (PQQ)
PQQ is a natural compound contained in quinoproteins (often found in bacteria), and is primarily retrieved from fermented soybeans. It is hypothesized that PQQ elevates metabolic rate via increasing the number of mitochondria within cells, a process referred to as mitochondrial biogenesis. Furthermore, PQQ appears to act as a cellular messenger that mimics some of the most basic effects of physical activity and increases the body’s production of the hormone irisin. 
In humans, Irisin release can be considered one of the most important effects 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.
Dosing—Placebo-controlled safety studies in humans show the consumption of PQQ at 20mg and 60mg per day is effective and safe. Timing is not important with PQQ.
So there you have it, 4 compounds to look for in supplements that will help boost your metabolic rate and propel your physique to a new level (assuming you eat and train properly). Always consider that supplements should not be the foundation of your plan to lose fat or build muscle, focus on diet, training and lifestyle factors first and foremost. After you have dialed those things in, then consider adding in some of the supplements listed in this guide to help give you a little boost (pun intended).
1. 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.
2. Yoshioka, M., Lim, K., Kikuzato, S., Kiyonaga, A., Tanaka, H., Shindo, M., & Suzuki, M. (1995). Effects of red-pepper diet on the energy metabolism in men.Journal of nutritional science and vitaminology, 41(6), 647.
3. Bose, M., Lambert, J. D., Ju, J., Reuhl, K. R., Shapses, S. A., & Yang, C. S. (2008). The major green tea polyphenol,(-)-epigallocatechin-3-gallate, inhibits obesity, metabolic syndrome, and fatty liver disease in high-fat–fed mice. The Journal of nutrition, 138(9), 1677-1683.
4. Shankar, S., Ganapathy, S., Hingorani, S. R., & Srivastava, R. K. (2007). EGCG inhibits growth, invasion, angiogenesis and metastasis of pancreatic cancer. Frontiers in bioscience: a journal and virtual library, 13, 440-452.
5. Hill, A. M., Coates, A. M., Buckley, J. D., Ross, R., Thielecke, F., & Howe, P. R. (2007). Can EGCG reduce abdominal fat in obese subjects?. Journal of the American College of Nutrition, 26(4), 396S-402S.
6. Arciero PJ, Gardner AW, Calles-Escandon J, Benowitz NL, Poehlman ET: Effects of caffeine ingestion on NE kinetics, fat oxidation, and energy expenditure in younger and older men.
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9. Kelly, D. P. (2012). Irisin, light my fire. Science, 336(6077), 42-43.