Whey protein, caffeine, green tea extract, yohimbe, etc. are the supplements that have the greatest amount of research to support their validity. 5-HTPS, MCTs, dietary fiber, theanine, and synephrine are secondary supplements that may work in some situations.



  • Whey protein, caffeine, green tea extract, yohimbe, etc. are the thermogenics that have the greatest amount of research to support their validity.

  • 5-HTPS, MCTs, dietary fiber, theanine, and synephrine are secondary thermogenics   that may work in some situations.


With the new year in progress, one of the most common goals is to lose weight.  One of the most common misconceptions is that exercise is more important than diet to lose weight. Surveys of college students indicate that 30-90% consider exercise more important than diet for weight loss. (Malinauskas et al., 2006; Wharton et al., 2008)

Exercise is great for health, but realistic expectations should be considered.  Well-established studies suggest that exercise alone is not likely to cause weight loss. (Pacy et al., 1986).

Weight Loss and Supplements

Many people on their weight loss journey look to natural ingredients and weight loss supplements (i.e., thermogenics) to reduce food cravings and burn stubborn fat. Still, this article will go thru the list of fat burner supplements/thermogenics and their research efficacy for fat loss.

Women are more likely to use thermogenics than men. In one polish survey, 84% of the respondents used energy drinks, and 60% used supplements as thermogenics. (Schlegel-Zawadzka & Barteczko, 2009)

Before examining the research on individual thermogenic supplements and their effect on body composition, let’s look at how to get rid of adipocytes (i.e., fat cells).  There are three types of fat cells: white adipose tissue (i.e., the majority of our fat cells), brown adipose tissue (i.e., serves as a source of body heat), and beige adipose tissue.

Brown adipose tissue is activated by cold exposure and certain drugs. Pharmaceutical companies are actively looking for drugs to increase BAT and beige adipose tissue because they contribute to increased calorie burning and weight loss. (Whittle et al., 2013)


City billboards display numerous ads for treatments that claim to reduce stomach fat using machines, including cooling devices like CoolSculpting. Instead of destroying fat cells, devices for Cryotherapy and cold exposure directly target the tissue to boost calorie burn through cold-induced thermogenesis. (Loap & Lathe, 2018) A 2015 literature review determined the safety and effectiveness of cryolipolysis for localized fat reduction. (Ingargiola et al., 2015) Researchers have shown that ice baths and cold water immersion can decrease body fat levels. (Espeland et al., 2022)

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Ice baths and cold water immersion have also been found to reduce body fat levels.(Espeland et al., 2022)



Most people think of fat cells like a piece of butter on a hot pan; you are melting fat when you exercise. Fat cells, unfortunately, don’t magically burn off; fat cell shrink, or they can expand. (Turcotte, 2000) We don’t lose fat cells; we empty our fat cells.

Fat cells are more like a balloon. The fat cell stays right where it is (i.e., arm, legs, stomach), but when on a calorie-restricted diet and exercise program, fat is liberated from the fat cell, and the fat cell becomes smaller. Thus, shrinking fat cells is how people look leaner and why it is hard to see muscle definition with high body fat.


Dietary supplements or thermogenics are advocated to “melt fat” or “burn fat” are commonly marketed to aid in weight loss. The best fat burner for men and women commonly has ingredients suggested to increase fat metabolism, burn more calories, and increase energy. Fat burners commonly called thermogenics contain caffeine, black pepper extract, green tea extract, green coffee bean extract, carnitine, conjugated linoleic acid (CLA), and chromium.

Thermogenicscan be divided into four categories: energy enhancers, protein and amino acids, adrenergic enhancers, and lean mass enhancers. (El-Zayat et al., 2019)    Thermogenic supplements stimulate weight loss through several molecular mechanisms, mainly boosting metabolism and suppressing appetite.

Examine.com is an amazing resource for supplements and thermogenic ingredients; check out their detailed research on fat-loss supplements guide.

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Any supplement should be at the very top of the pyramid, whereas diet and exercise will be the foundation of fat loss.


Primary thermogenics (best safety-efficacy profile) should be the first-choice supplements.

Whey protein and Casein supplements.

The benefits of having adequate protein for increasing lean muscle mass and fat loss are backed by numerous research studies. (Leidy et al., 2015; Moon & Koh, 2020; Te Morenga & Mann, 2012)

Protein supplements such as whey protein have been shown to increase calories burned by increasing metabolic rate. Protein has a greater thermic effect of food (i.e., the amount of energy expended during digestion which increases overall calories burned). Whey protein has also been shown to increase several appetite-reducing hormones such as GLP-1, Ghrelin, etc. (Mollahosseini et al., 2017; Rigamonti et al., 2019)

People looking for weight loss should get at least .6-1 gram of protein per pound of body weight. Protein intake should be evenly distributed throughout the day, with 20-40 grams per meal. (Jäger et al., 2017)


Caffeine is a stimulant and thermogenic. Iu can increase heat production and fat mobilization. A 2019 review of the literature found that caffeine intake was associated with weight loss and body fat reduction. (Tabrizi et al., 2019)

Green Tea Extract (ECGC) is associated with modulations of fat metabolism and consequent weight loss. Many companies will refer to green tea as a natural thermogenic. Studies have found that green tea extract has been found to enhance fat metabolism and fat loss. (Lin et al., 2020; Rondanelli et al., 2021)

Yohimbe is an alpha-2-receptor antagonist (a2-blocker), which causes an increase in the body’s noradrenaline production (i.e., fight or flight response). A previous study showed that in a group of football players who used yohimbine, there was no improvement in performance; however, a slight effect of this compound on the reduction of adipose tissue was demonstrated. (Ostojic, 2006) Side effects are associated with yohimbe, such as increased

Secondary supplements (Maybe be helpful) may provide fat loss benefits. These should not be first-choice supplements.

5-HTP is a supplement shown to raise serotonin, help with mood, and reduce cravings. A 2020 study found that 100 mg of 5-HTP led to significant reductions in body fat, but not lean body mass, total body water, and % body fat. (Evans et al., 2022)

Dietary Fiber is necessary for health and wellness. Fiber has been suggested to reduce appetite. A 2022 study found that not all fibers are the same. The study found that different fibers had different effects on blood lipids.  A variety of fibers should be included in the diet for optimal health. (Vuksan et al., 2011)

MCT is a class of fatty acids that are metabolized faster than regular fatty acids. MCTs are commonly found in coconut oil but can also be found in palm oil and dairy products. A 2021 review of the literature found that MCTs can reduce food intake, but the mechanism is unclear because MCTs do not decrease appetite or hormones related to appetite. (Maher & Clegg, 2021)

Synephrine is the most commonly used species in dietary supplements is C. aurantium. Synephrine is a close structural analog of ephedrine. It is often used in combination with caffeine in most fat burners. Studies have shown that acute synephrine results in enhanced fat mobilization. (Gutiérrez-Hellín & Del Coso, 2016)

A 2012 review of the literature found that synephrine was associated with increased metabolic rate and burned calories with a modest decrease in weight loss. (Stohs et al., 2012)

Theanine is often included in fat burners, not because it directly stimulates fat loss but because it reduces the stimulating effects of caffeine, resulting in a calming effect. (Dodd et al., 2015; Hidese et al., 2019)

Promising supplements have less evidence for their effects. These ingredients include guarana and yerba mate.

Unproven supplements (no research to support claims of fat loss).

Berberine, Coleus forskohlii, green coffee extract, fucoxanthin, raspberry ketones, hoodia gordonii, garcinia cambogia

There are risks associated with thermogenics. A 2021 review of the literature found that pre-workouts, thermogenics, brain boosters, and hormone boosters have the highest risk of containing harmful substances; some have been associated with life-threatening consequences. (Jędrejko et al., 2021) Furthermore, a 2021 review of the literature examining fat burners found limited evidence for using thermogenics in overweight individuals. (Clark & Welch, 2021)

Any supplement should be at the very top of the pyramid, whereas diet and exercise will be the foundation of fat loss. Plenty of studies show that diet and exercise alone can reduce body fat, whereas fat burners may contribute to fat loss. Always check with a qualified medical professional before deciding to take any thermogenic.


Clark, J. E., & Welch, S. (2021). Comparing effectiveness of fat burners and thermogenic supplements to diet and exercise for weight loss and cardiometabolic health: Systematic review and meta-analysis. Nutr Health, 27(4), 445-459. https://doi.org/10.1177/0260106020982362

Dodd, F. L., Kennedy, D. O., Riby, L. M., & Haskell-Ramsay, C. F. (2015). A double-blind, placebo-controlled study evaluating the effects of caffeine and L-theanine both alone and in combination on cerebral blood flow, cognition and mood. Psychopharmacology (Berl), 232(14), 2563-2576. https://doi.org/10.1007/s00213-015-3895-0

El-Zayat, S. R., Sibaii, H., & El-Shamy, K. A. (2019). Physiological process of fat loss. Bulletin of the National Research Centre, 43(1), 208. https://doi.org/10.1186/s42269-019-0238-z

Espeland, D., de Weerd, L., & Mercer, J. B. (2022). Health effects of voluntary exposure to cold water – a continuing subject of debate. International Journal of Circumpolar Health, 81(1), 2111789. https://doi.org/10.1080/22423982.2022.2111789

Evans, C., Mekhail, V., Curtis, J., Czartoryski, P., Kaminski, J., Ellerbroek, A., Bustillo, E., Jiannine, L., Santana, J. C., & Antonio, J. (2022). The Effects of 5-HTP on Body Composition: An 8-Week Preliminary RCT. Journal of Dietary Supplements, 1-10. https://doi.org/10.1080/19390211.2022.2076760

Gutiérrez-Hellín, J., & Del Coso, J. (2016). Acute p-synephrine ingestion increases fat oxidation rate during exercise. Br J Clin Pharmacol, 82(2), 362-368. https://doi.org/10.1111/bcp.12952


Hidese, S., Ogawa, S., Ota, M., Ishida, I., Yasukawa, Z., Ozeki, M., & Kunugi, H. (2019). Effects of L-Theanine Administration on Stress-Related Symptoms and Cognitive Functions in Healthy Adults: A Randomized Controlled Trial. Nutrients, 11(10). https://doi.org/10.3390/nu11102362

Ingargiola, M. J., Motakef, S., Chung, M. T., Vasconez, H. C., & Sasaki, G. H. (2015). Cryolipolysis for fat reduction and body contouring: safety and efficacy of current treatment paradigms. Plast Reconstr Surg, 135(6), 1581-1590. https://doi.org/10.1097/prs.0000000000001236

Jäger, R., Kerksick, C. M., Campbell, B. I., Cribb, P. J., Wells, S. D., Skwiat, T. M., Purpura, M., Ziegenfuss, T. N., Ferrando, A. A., Arent, S. M., Smith-Ryan, A. E., Stout, J. R., Arciero, P. J., Ormsbee, M. J., Taylor, L. W., Wilborn, C. D., Kalman, D. S., Kreider, R. B., Willoughby, D. S., . . . Antonio, J. (2017). International Society of Sports Nutrition Position Stand: protein and exercise. Journal of the International Society of Sports Nutrition, 14(1), 20. https://doi.org/10.1186/s12970-017-0177-8


Jędrejko, K., Lazur, J., & Muszyńska, B. (2021). Risk Associated with the Use of Selected Ingredients in Food Supplements. Chem Biodivers, 18(2), e2000686. https://doi.org/10.1002/cbdv.202000686

Leidy, H. J., Clifton, P. M., Astrup, A., Wycherley, T. P., Westerterp-Plantenga, M. S., Luscombe-Marsh, N. D., Woods, S. C., & Mattes, R. D. (2015). The role of protein in weight loss and maintenance. Am J Clin Nutr, 101(6), 1320s-1329s. https://doi.org/10.3945/ajcn.114.084038

Lin, Y., Shi, D., Su, B., Wei, J., Găman, M.-A., Sedanur Macit, M., Borges do Nascimento, I. J., & Guimaraes, N. S. (2020). The effect of green tea supplementation on obesity: A systematic review and dose–response meta-analysis of randomized controlled trials. Phytotherapy Research, 34(10), 2459-2470. https://doi.org/https://doi.org/10.1002/ptr.6697

Loap, S., & Lathe, R. (2018). Mechanism Underlying Tissue Cryotherapy to Combat Obesity/Overweight: Triggering Thermogenesis. Journal of obesity, 2018, 5789647. https://doi.org/10.1155/2018/5789647


Maher, T., & Clegg, M. E. (2021). A systematic review and meta-analysis of medium-chain triglycerides effects on acute satiety and food intake. Crit Rev Food Sci Nutr, 61(4), 636-648. https://doi.org/10.1080/10408398.2020.1742654

Malinauskas, B. M., Raedeke, T. D., Aeby, V. G., Smith, J. L., & Dallas, M. B. (2006). Dieting practices, weight perceptions, and body composition: A comparison of normal weight, overweight, and obese college females. Nutrition Journal, 5(1), 11. https://doi.org/10.1186/1475-2891-5-11

Mollahosseini, M., Shab-Bidar, S., Rahimi, M. H., & Djafarian, K. (2017). Effect of whey protein supplementation on long and short term appetite: A meta-analysis of randomized controlled trials. Clinical Nutrition ESPEN, 20, 34-40. https://doi.org/10.1016/j.clnesp.2017.04.002

Moon, J., & Koh, G. (2020). Clinical Evidence and Mechanisms of High-Protein Diet-Induced Weight Loss. J Obes Metab Syndr, 29(3), 166-173. https://doi.org/10.7570/jomes20028

Ostojic, S. M. (2006). Yohimbine: the effects on body composition and exercise performance in soccer players. Res Sports Med, 14(4), 289-299. https://doi.org/10.1080/15438620600987106

Pacy, P. J., Webster, J., & Garrow, J. S. (1986). Exercise and Obesity. Sports Medicine, 3(2), 89-113. https://doi.org/10.2165/00007256-198603020-00002


Rigamonti, A. E., Leoncini, R., Casnici, C., Marelli, O., Col, A., Tamini, S., Lucchetti, E., Cicolini, S., Abbruzzese, L., Cella, S. G., & Sartorio, A. (2019). Whey Proteins Reduce Appetite, Stimulate Anorexigenic Gastrointestinal Peptides and Improve Glucometabolic Homeostasis in Young Obese Women. Nutrients, 11(2). https://doi.org/10.3390/nu11020247

Rondanelli, M., Riva, A., Petrangolini, G., Allegrini, P., Perna, S., Faliva, M. A., Peroni, G., Naso, M., Nichetti, M., Perdoni, F., & Gasparri, C. (2021). Effect of Acute and Chronic Dietary Supplementation with Green Tea Catechins on Resting Metabolic Rate, Energy Expenditure and Respiratory Quotient: A Systematic Review. Nutrients, 13(2). https://doi.org/10.3390/nu13020644

Schlegel-Zawadzka, M., & Barteczko, M. (2009). Ocena stosowania suplementów diety pochodzenia naturalnego w celach prozdrowotnych przez osoby dorosłe. Zywnosc-nauka Technologia Jakosc, 16.

Sommer, M., Braumann, M., Althoff, T., Backhaus, J., Kordon, A., Junghanns, K., Ehrenthal, D., Bartmann, U., Hohagen, F., & Broocks, A. (2011). Psychological and neuroendocrine responses to social stress and to the administration of the alpha-2-receptor antagonist, yohimbine, in highly trained endurance athletes in comparison to untrained healthy controls. Pharmacopsychiatry, 44(4), 129-134. https://doi.org/10.1055/s-0031-1277166

Stohs, S. J., Preuss, H. G., & Shara, M. (2012). A review of the human clinical studies involving Citrus aurantium (bitter orange) extract and its primary protoalkaloid p-synephrine. Int J Med Sci, 9(7), 527-538. https://doi.org/10.7150/ijms.4446


Tabrizi, R., Saneei, P., Lankarani, K. B., Akbari, M., Kolahdooz, F., Esmaillzadeh, A., Nadi-Ravandi, S., Mazoochi, M., & Asemi, Z. (2019). The effects of caffeine intake on weight loss: a systematic review and dos-response meta-analysis of randomized controlled trials. Crit Rev Food Sci Nutr, 59(16), 2688-2696. https://doi.org/10.1080/10408398.2018.1507996

Te Morenga, L., & Mann, J. (2012). The role of high-protein diets in body weight management and health. British Journal of Nutrition, 108(S2), S130-S138. https://doi.org/10.1017/S0007114512002437

Turcotte, L. P. (2000). Muscle fatty acid uptake during exercise: possible mechanisms. Exerc Sport Sci Rev, 28(1), 4-9.


Vuksan, V., Jenkins, A. L., Rogovik, A. L., Fairgrieve, C. D., Jovanovski, E., & Leiter, L. A. (2011). Viscosity rather than quantity of dietary fibre predicts cholesterol-lowering effect in healthy individuals. Br J Nutr, 106(9), 1349-1352. https://doi.org/10.1017/s0007114511001711

Wharton, C. M., Adams, T., & Hampl, J. S. (2008). Weight Loss Practices and Body Weight Perceptions Among US College Students. Journal of American College Health, 56(5), 579-584. https://doi.org/10.3200/JACH.56.5.579-584

Whittle, A., Relat-Pardo, J., & Vidal-Puig, A. (2013). Pharmacological strategies for targeting BAT thermogenesis. Trends Pharmacol Sci, 34(6), 347-355. https://doi.org/10.1016/j.tips.2013.04.004

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