Jump to

Farrinstitute is reader-supported. We may receive commissions on purchases made through links on our site.

Appetite Suppressants: The Science Behind | Farr Institute

Appetite Suppressants: The Science Behind | Farr Institute

By Kire Stojkovski M.D
Editor akhila Published 02 June 2023
Time to read 6 min

Hunger is very helpful; it is the body’s way of ensuring we don’t starve. It’s not too convenient when you’re trying to lose weight, though. However hard you may try, hunger and increased appetite will probably see you breaking your diet.

That needn’t be the case. Appetite suppressants are designed to control your cravings, allowing you to pursue your weight loss goals without too much trouble.

The 5 most effective appetite suppressants we found:

  • PhenQ — Best Appetite Suppressant Overall
  • Zotrim — Additional Ingredients for Weight Loss
  • Instant Knockout — Best Suppressant for Training
  • LeanBean – Powerful Fat Burner that Also Controls Appetite
  • Garcinia Extra – The problem is that there are just too many options in the market today. This article separates fact from fat by taking a scientific approach and reviewing each product according to the most recent scientific literature.


Let’s look at the11 best appetite suppressants in 2020, and what they have to offer — according to science, not to manufacturer promises.

Top 10 Appetite Suppressants

1. PhenQ

This appetite suppressant is very popular among people seeking to lose weight quickly: Because it causes the body to burn its fat reserves while also preventing the formation of new fat cells. PhenQ has also been recorded to improve moods. You’ll find this feature very useful if you plan to eat better and cut down your caloric intake; because dieting makes you cranky [1].

How it Works

PhenQ has six active ingredients:

  • α-Lacys Reset
  • Capsimax Powder
  • Chromium Picolinate
  • Caffeine
  • Nopal

α-Lacys Reset® (all rights reserved) is a combination of Alpha Lipoic Acid (ALA) and Cysteine. ALA has strong anti-obesity properties, and Cysteine has been demonstrated to suppress appetite in humans. The two help you combat excess body weight by controlling hunger, and calorie intake by extension [2][3].

Capsimax Powder is a blend of capsicum, caffeine, Piperine, and vitamin B3. Capsicum and Piperine are thermogenic, meaning they cause your body to heat up and burn fat reserves. Studies have shown that Piperine stops the formation of new fat cells, making it a very worthwhile addition to your weight management program [4][5].

Hunger and increased appetite are the body’s way of reminding you to eat and replenish your energy stores. Products with Capsimax Powder ensure that you get enough energy from your fat reserves, effectively controlling your hunger and appetite [4][5].

Chromium Picolinate controls your sugar levels by checking your carb and sugar cravings [6]. It does these by enhancing the absorption of glucose at the cellular level, ensuring that you get enough energy from the little food you consume [7][8].

L-CARNITINE is an amino acid that occurs naturally in nuts, vegetables, and red meat. Per recent studies, it aids the conversion of fat reserves into energy. The more energy you have, the less likely you are to experience hunger pangs [9][10].

Caffeine is very popular in appetite suppression supplements, and for a good reason. It’s a well-documented source of natural hunger suppression. It’s also been recorded to increase thermogenesis (natural fat burning process), boosting your energy levels [11][12][13].

Nopal is a high-fiber cactus that’s also very rich in amino acids. A high-fiber content is associated with increased satiety, and less hunger [14]. Amino acids have a very high-energy value, reducing the need and desire to snack up [15].

PhenQ Side Effects

PhenQ is made of all-natural ingredients and shouldn’t have any side effects. That said, our bodies are different, some being more sensitive than others. Some users experienced mild bloating, nausea, and headaches for a few days.

Read the Full PhenQ Review

PhenQ​ Official Website

2. Zotrim

Zotrim is very popular in the weight loss community because of its ability to control hunger and food cravings. Some studies have documented Zotrim to help people lose weight and even outperformed three major prescription drugs in this regard.[16]

How it Works

Zotrim is a patented combination of 6 ingredients:

  • Yerba Mate
  • Damiana
  • Guarana
  • Caffeine
  • Vitamins B3 and B6

Yerba Mate is a South American leaf extract that has a long history as an appetite suppressant. It increases your body’s energy levels while also pumping you full of antioxidants that have been documented to prevent many diseases [17][18]. Some studies further revealed that this extract could help prevent the development of fat cells, complementing weight loss programs [19].

Damiana is excellent if you use food as a coping mechanism. It regulates your moods, suppressing the urge to eat when things are a little tough [20].

Guarana has been documented to raise metabolism levels. Studies further revealed that it enhances thermogenesis by causing more fat to be released into the bloodstream. Once in the bloodstream, the fat acts as a source of energy, reducing the burden for more food. Consequently, your hunger response and appetite are toned down [21] [22]. It’s very popular in weight loss pills designed to be taken alongside exercise.

Caffeine makes Zotrim an excellent appetite suppressant for people who want to reduce their food intake while adding a bit of exercise to their weight loss program. Caffeine boosts your moods and enhances your concentration, helping you stay motivated through the exercising period [12] [13].

Vitamins B3 and B6 enhance the conversion of food into energy while also reducing feelings of fatigue and tiredness. Not only will the high energy levels reduce your appetite, but it will also keep you energized, maximizing your exercise potential [23][24].

Zotrim Side Effects

Zotrim supplements may cause nausea in first-time users, only for a few days, though. A small fraction of users reported mild allergic reactions, but this is very rare. Zotrim is all-natural and should be perfectly safe.

Read the Full Zotrim Review

3. Instant Knockout

Instant knockout is side effect free, and very potent as an appetite suppressant. It’s all-natural ingredients also double as fat burners, making it an excellent choice if you’re looking for supplements to add to your weight loss program.

How it Works

Instant knockout has 9 active ingredients:

  • Vitamins B6 and B12
  • Glucomannan
  • Cayenne Pepper Seeds
  • Caffeine Anhydrous
  • Green Tea Extract
  • Chromium
  • Zinc
  • Piperine
  • Green Coffee Bean

Vitamins B6 and B12 are documented to boost metabolism and trigger the oxidation of fats, enhancing weight loss. Vitamin B12 has been linked to increased energy production, increasing the amount of energy present in our bodies, reducing hunger pangs and controlling appetite [25][26].

Glucomannan is a natural fiber that helps you lose weight by increasing the length of satiety. When you feel full, your hunger response and appetite are suppressed. It’s a popular ingredient among products [27].

Cayenne Pepper Seeds are thermogenic. That means they increase your body’s metabolism, especially concerning the burning of fats. When you get your energy from fat reserves, you lose weight and have a lot of energy in your body without necessarily having to snack up. This curbs your appetite [28] [29].

Caffeine Anhydrous is a roasted coffee bean extract, which boosts your moods. It also enhances your energy and metabolic rates and has been documented to reduce fatigue — a welcome property if you plan on working out [30]. . Multiple studies have demonstrated caffeine’s thermogenic properties [12][13].

Green Tea Extract is full of bioactive ingredients that have been documented to boost fat oxidation, enhance weight loss, as well as hinder fat deposition. It’s also associated with optimized blood pressure [31].

Chromium, as evidenced by studies, influences insulin sensitivity, controlling how your body processes carbohydrates, leading to heightened energy levels [32].

Zinc deficiency is associated with obesity. This mineral helps us process carbohydrates and fats by enhancing the relevant metabolic processes. It’s been known to reduce appetite, making it a very popular mineral in weight loss pills [33].

Piperine enhances metabolism and inhibits fat formation. Its thermogenic properties make it a very useful addition to any weight management initiative [4] [5].

Green Coffee Bean extracts are rich in chlorogenic acid, which has been documented to reduce appetite and sugar cravings[34].

Instant Knockout Side effects

The abundance of caffeine could result in headaches, especially for people who are not used to it. You should also try as much as possible to avoid taking these supplements too close to your bedtime, or you’ll have disturbed sleep.

Read the Full Instant Knockout Review

Visit the Instant Knockout​ Official Website

4. LeanBean

Leanbean works by suppressing your appetite while also boosting fat metabolism. Increased metabolism is associated with increased levels of energy and sharper focus. This energy fuels your body for longer, slowing your hunger response.

How it Works

Leanbean has 4 main active ingredients:

  • Konjac Fiber
  • Choline
  • Vitamins B6 and B12
  • Chromium Picolinate

Konjac Fiber (glucomannan) is a dietary fiber that suppresses hunger by increasing satiety. Leanbean contains 3 grams of glucomannan per dose, making it one of the most fiber-rich appetite suppressant pills in the market today. Research has shown that appetite suppression is harder for women, the increased fiber should help [37][38].

Choline, a nutrient synthesized in the liver, has been documented to enhance fat metabolism, providing your body with sufficient energy for day-to-day activities. That said, this mineral is synthesized in very minute amounts, we have to supplement it through the food we consume [16].

Vitamins B6 and B12 are associated with reduced fatigue and enhanced muscle function. They are also important to the health of your nervous system and have been shown to improve moods[25] [26] [39]. They are excellent additions to your weight management initiative, especially if emotional eating has been a problem for you.

Chromium Picolinate supplements reduce appetite by increasing the amount of energy available to your body. It has been demonstrated to enhance glucose intake at the cellular level, allowing you to get more energy without upping your caloric intake [6] [7] [8].

Leanbean Side Effects

This over the counter appetite suppressant isn’t too linked to side effects. Its all-natural formula is very easy on your body, but it’s not advisable for pregnant women. Consult a doctor for further guidance in such cases.


Read the Full Leanbean Review

5. Garcinia Extra

This natural appetite suppressant is derived from the Garcinia Cambogia fruit and raspberry ketones. Garcinia Cambogia is well documented to prevent fat from being synthesized, as well as suppressing hunger and appetite.

How it Works

Garcinia extra is derived from two fruits:

  • Garcinia Cambogia
  • Raspberry Ketones

Garcinia Cambogia has been linked to increased fat oxidation, making it one of the best appetite suppressants to add to your weight loss routine. It’s also been documented to be very potent as a hunger suppressant [40].

Raspberry Ketones have been documented to increase the rate of fat oxidation, regulating your body weight. This increased energy keeps you feeling upbeat and motivated for exercise [41].

Garcinia Extra Side Effects

First-time users may experience mild nausea, but you do get used to it. For the most part, there are no side effects associated with these natural supplements. Just don’t do weight management when you’re pregnant.

Visit the Garcinia Extra ​Official Website

6. Powher

Powher is marketed as a fat burner, but it’s also filled with research-verified appetite control ingredients. The company recommends 2 capsules, 3 times a day, each dose supplying 1 gram of Konjac Fiber. The product is also rich in choline, glucomannan, natural caffeine, iron, chromium, selenium, and magnesium.

Konjac Fiber makes the bulk of each serving, meaning you will be fuller for longer, reducing hunger. This ingredient is well reported in health news cycles for its ability to reduce calorie intake without causing sudden energy dips [35] [36].

Visit the Powher ​Official Website

7. Phen24

Your metabolism is under the influence of the circadian rhythm. The metabolic rate is highest during the day and lowest during the night. During the day, your body burns off a little of your fat reserves. In the night, however, low metabolism increases the risk that more calories will be converted into fat — reversing most of the gains you made in the day [42].

Phen24 supplements come in two variants designed to match your circadian rhythm and boost metabolism to peak levels, independent of time of day. Increased thermogenesis at night is especially helpful if you’re looking to stop nighttime snacking.

Phen24 is rich in cayenne powder, L-phenylalanine, grammar extracts, caffeine, iodine, manganese, copper, and zinc. These ingredients are designed to keep you feeling energized and increase your resting metabolism without exercise.

Visit the Phen24 ​Official Website

8. Trimtone

Trimtone is a natural fat burner, and also a very potent hunger suppressant. Its special formula boosts mood metabolism levels even when you’re at rest. You only need to take one capsule a day, making it an excellent suppressant for the busy working woman.

It is rich in caffeine, green coffee, green tea, grains of paradise, and glucomannan. Grains of Paradise is a herb from the ginger family that enhances thermogenesis. It’s been shown to regulate blood sugar levels, keeping your energy constant throughout the day. This makes it less likely for you to experience cravings [43].

These over the counter supplements are best taken a few hours before your bedtime

Read the Full Trimtone Review

Visit the Trimtone ​Official Website

9. Atrafen Elite

Atrafen Elite helps you lose weight by curbing your cravings and helping you burn fat. It also increases your energy and mental focus to reduce the likelihood that you will eat to cope with stress. The primary ingredients in this product are raspberry ketones, caffeine, green tea, acai fruit African mangos, and grapefruit powder.

Atrafen Elite is an all-natural product. It lowers food intake without causing sudden energy dips. If you’re looking for easy to use supplements with proven body regulation properties, Atrafen pills are worth our consideration.

Check the Best Price of Atrafen Elite

10. Genius Diet Pills

Genius Diet Pills are rich in SATIEREAL® Saffron (all rights reserved), which was observed to reduce sugar cravings — by upwards of 70% per the manufacturer. Participants who took the ingredient experienced the 55% reduction in their snack times [44].

Genius Diet Pills contain 100 milligrams of 5-HTP, which triggers the release of serotonin (the feel-good hormone). This is hugely beneficial in the regulation of emotional eating. Studies have revealed that it boosts your moods, so you won’t have to turn to food[45].

Check the Best Price of Genius Diet Pills

How Can an Appetite Suppressant Help Me?

Appetite suppressants help you lose weight faster than weight loss pills, independent of exercise.

When combating excess weight, you often have to diet, exercise, or do both. As effective as these two strategies are, the results take longer than most people have the patience for. Additionally, self-discipline plays a very big role in the maintenance of these two habits. This is where appetite suppressant pills come in.

These pills help you eat less by controlling your hunger and decreasing your appetite, independent of the strength of your will, or lack thereof. The best ones in the market come with thermogenic ingredients that naturally enhance the oxidation of fat. Some have even been documented to prevent the formation of new fat cells.

Will These Appetite Suppressants Help Me Lose Weight?

Yes. All the appetite suppressants on this list have a well-documented history of helping people shed off pounds fast. Just remember that these suppressants are only as effective as your dedication to the manufacturer’s recommended dosage.

How Do Appetite Suppressants Work?

Hunger and appetite are your body’s reminder that you need to eat and boost your energy levels. Natural appetite suppressants interfere with the hunger response in three ways:

Keeping You Feeling Full

Suppressant appetite pills are typically very rich in fiber. Fiber stays longer in your stomach, making you feel full. An empty stomach is usually the trigger for the hunger response: The fuller you feel, the lower your appetite.

Glucomannan is an especially important fiber in this regard. It’s water-soluble, among the most viscous fibers known today. Once in your gut, it absorbs water and expands to fill your stomach for longer.[27]

Increasing Available Energy

Hunger is all about energy. If you can keep your energy levels high without eating extra, you can control your appetite. Thermogenic hunger suppressants increase your energy levels by boosting fat oxidation — the burning of fats to produce energy.

Some appetite management pills increase your energy by enhancing the digestive process. B Vitamins are a great example of minerals that boost the amount of energy you get from your food [23] [24].

Mitigating Emotional Eating

Eating is often used as a coping mechanism. To suppress the appetite, some pills contain minerals like B vitamins and caffeine, which have been documented to help your moods — essential when you want to include exercise in your weight loss management program. They also help you overcome the crankiness that is brought about by dieting [1] [12] [13].

How to Use Appetite Suppressants?

Each suppressant is unique, always follow the manufacturer’s recommended dosage. Also, be mindful of the time of dosage. Pills that have a high-fiber content, especially glucomannan, are best taken before a meal. Pills with high-caffeine content are also time-sensitive. If you take them too late into the day, they’ll interfere with your sleep.

Are There Any Side-Effects When Using Appetite Suppressants?

Anything suppressing appetite affects your metabolism and is sure to have an effect on how your body operates. Natural appetite suppression is pretty harmless in this regard. Most side-effects recorded are typically from reactions with other medications.

As a rule of thumb, always consult a doctor if you have any underlying conditions, or are currently on some other medication, before popping anti-appetite pills.

All the hunger suppressants featured in this article are all-natural, minimizing the risk of reaction. That said, you need to be sure that they won’t interfere with, or react with, any current medications you’re taking.

You should also consult a doctor if you’re pregnant. Pregnancy is highly influenced by hormonal changes: These pills have been shown to influence your hormones — partly because they affect metabolism.

What’s the Difference Between Appetite Suppressants and Other Types of Weight Loss Pills?

Most weight loss pills are prescription drugs, DEA schedule IV. Traditional appetite suppressants are nonprescription.

Only five weight loss compounds are FDA approved: liraglutide, naltrexone-bupropion, orlistat, phentermine, and phentermine-topiramate. If you must take weight loss pills, only get them by prescription, and even then, only from approved outlets.

The 11 appetite suppressants discussed in this article are all natural — meaning they contain no synthetic compounds whatsoever. The advantage of this is that the risk of allergic reaction is greatly reduced.

In a Nutshell

It is important that you manage your appetite and cravings as you work towards a healthier diet and lifestyle. Appetite suppressants help you manage your weight even before you get a handle on the discipline necessary to nurture healthier habits. The products featured on this list are all-natural.

A good number of these products have moneyback guarantees. You can buy, test them, and return them if they don’t deliver on the promises. That said, it’s always important to seek the opinion of a medical professional if you have underlying health issues, or you’re pregnant.

{ “@context”: “https://schema.org”, “@type”: “Article”, “mainEntityOfPage”: { “@type”: “WebPage”, “@id”: “https://farrinstitute.org/best-appetite-suppressants/” }, “headline”: “5 Best Appetite Suppressants: Here’s the Science Behind Pills Designed to Curb Hunger”, “description”: “Hunger is very helpful; it is the body’s way of ensuring we don’t starve. It’s not too convenient when you’re trying to lose weight, though. However hard you may try, hunger and increased appetite will probably see you breaking your diet.”, “image”: “https://farrinstitute.org/wp-content/uploads/2021/03/Best-Appetite-Suppressants.png.webp”, “author”: { “@type”: “”, “name”: “Jonathan Hoarau”, “url”: “https://farrinstitute.org/author/jonathan-hoarau/” }, “publisher”: { “@type”: “Organization”, “name”: “Farr Institute”, “logo”: { “@type”: “ImageObject”, “url”: “https://farrinstitute.org/” } }, “datePublished”: “2020-12-29”, “dateModified”: “2023-05-29” }


1. The Psychological Effects of Short-Term Fasting in Healthy Women. East London and City Foundation NHS Trust, London, UK, University College London, London, UK. 2016, Aug. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4992682/

2. Alpha-Lipoic Acid (ALA) as a supplementation for weight loss: Results from a Meta-Analysis of Randomized Controlled Trials. Suat Kucukgoncu, Yale University School of Medicine, Department of Psychiatry. 2017 May. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5523816/

3. l-cysteine suppresses ghrelin and reduces appetite in rodents and humans. 1Department of Investigative Medicine, Imperial College London, London, UK. AstraZeneca R&D, Mölndal, Sweden. Division of Diabetes & Nutritional Sciences, King’s College London, London, UK. NextRx, Gothenburg, Sweden. Department of Investigative Medicine, Imperial College London, Commonwealth Building, Du Cane Road, London. 2014 Oct. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4276721/

4. Acute Effects of Capsaicin on Energy Expenditure and Fat Oxidation in Negative Energy Balance. Department of Human Biology, School for Nutrition, Toxicology and Metabolism (NUTRIM), Maastricht University, Maastricht, The Netherlands. 2013 July. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3699483/

5. The Effects of Capsaicin and Capsiate on Energy Balance: Critical Review and Meta-analyses of Studies in Humans. Department of Nutrition Science, Purdue University, 212 Stone Hall, 700 West State Street, West Lafayette, IN 47907-2059, USA. 2011 Oct. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3257466/

6. Dietary Chromium Supplementation for Targeted Treatment of Diabetes Patients with Comorbid Depression and Binge Eating. 2015 Jul; 85(1): 45–48.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4529062/

7. The Biochemistry of Chromium. The Journal of Nutrition, Volume 130, Issue 4. April 2000; Pages 715–718. https://academic.oup.com/jn/article/130/4/715/4686593

8. Molecular mechanisms of chromium in alleviating insulin resistance. College of Health Sciences, School of Pharmacy, Center for Cardiovascular Research and Alternative Medicine, University of Wyoming, Laramie, WY 82071, USA.012 Apr;23(4):313-9. https://pubmed.ncbi.nlm.nih.gov/22423897/

9. The effects of a fat loss supplement on resting metabolic rate and hemodynamic variables in resistance trained males: a randomized, double-blind, placebo-controlled, cross-over trial.Journal of the International Society of Sports Nutrition. 2016 April. https://jissn.biomedcentral.com/articles/10.1186/s12970-016-0125-z

10. L-Carnitine treatment reduces severity of physical and mental fatigue and increases cognitive functions in centenarians: a randomized and controlled clinical trial.2007 Dec;86(6):1738-44.https://pubmed.ncbi.nlm.nih.gov/18065594/

11. Caffeine, coffee, and appetite control: a review.Department of Kinesiology , Auburn University at Montgomery , Montgomery , AL , USA. 2017 Dec;68(8):901-912. https://pubmed.ncbi.nlm.nih.gov/28446037/

12. Metabolic effects of caffeine in humans: lipid oxidation or futile cycling? Nestlé Research Center, Lausanne, Switzerland. kevin.acheson@rdls.nestle.com. 2004 Jan;79(1):40-6. https://pubmed.ncbi.nlm.nih.gov/14684395/

13. Effect of different amounts of coffee on dietary intake and appetite of normal-weight and overweight/obese individuals. Department of Nutrition and Dietetics, Harokopio University, Athens, Greece. 2013 Jun;21(6):1127-32. https://pubmed.ncbi.nlm.nih.gov/23671022/

14. The effect of fiber on satiety and food intake: a systematic review. Department of Food Science and Nutrition, University of Minnesota, Saint Paul, Minnesota 55108, USA. 2013;32(3):200-11. https://pubmed.ncbi.nlm.nih.gov/23885994/

15. Protein, amino acids and the control of food intake. INRA, Paris, France. 2009 Jan;12(1):54-8. https://pubmed.ncbi.nlm.nih.gov/19057188/

16. The positive effects of yerba maté (Ilex paraguariensis) in obesity. Laboratory of Microbiology and Molecular Biology, Clinical Pharmacology and Gastroenterology Unit, Sao Francisco University Medical School, Av São Francisco de Assis 218, Bragança Paulista, SP 12916-900, Brazil. alessandra.gambero@usf.edu.br. 2015 Jan 22;7(2):730-50. https://pubmed.ncbi.nlm.nih.gov/25621503/

17. Polyphenolic compounds, antioxidant capacity, and quinone reductase activity of an aqueous extract of Ardisia compressa in comparison to mate (Ilex paraguariensis) and green (Camellia sinensis) teas. Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, 228 ERML, MC-051, 1201 W Gregory Drive, Urbana, Illinois 61801, USA. 2004 Jun 2;52(11):3583-9. https://pubmed.ncbi.nlm.nih.gov/15161234/

18. Polyphenolic compounds, antioxidant capacity, and quinone reductase activity of an aqueous extract of Ardisia compressa in comparison to mate (Ilex paraguariensis) and green (Camellia sinensis) teas. Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, 228 ERML, MC-051, 1201 W Gregory Drive, Urbana, Illinois 61801, USA. 2004 Jun 2;52(11):3583-9. https://pubmed.ncbi.nlm.nih.gov/15161234/

19. Anti-obesity and anti-diabetic effects of Yerba Mate (Ilex paraguariensis) in C57BL/6J mice fed a high-fat diet. Huvet Co. Ltd, Iksan, Korea. 2012 Mar;28(1):23-9. https://pubmed.ncbi.nlm.nih.gov/22474471/

20. Pharmacological evaluation of Bioactive Principle of Turnera aphrodisiaca. University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh-160 014, India. 2008 Nov-Dec; 70(6): 740–744. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3040867/

21. Guarana (Paullinia cupana) Stimulates Mitochondrial Biogenesis in Mice Fed High-Fat Diet. Laboratory of Immunopharmacology and Molecular Biology, Clinical Pharmacology and Gastroenterology Unit, Sao Francisco University Medical School, Av Sao Francisco de Assis, 218, Braganca Paulista-SP 12916-900, Brazil. 2018 Feb; 10(2): 165. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5852741/

22. Effects of encapsulated green tea and Guarana extracts containing a mixture of epigallocatechin-3-gallate and caffeine on 24 h energy expenditure and fat oxidation in men. Division of Kinesiology, Laval University, Ste-Foy, Québec, Canada, G1K 7P4. 2005 Sep;94(3):432-6. https://pubmed.ncbi.nlm.nih.gov/16176615/

23. B Vitamins and the Brain: Mechanisms, Dose and Efficacy—A Review. Brain, Performance and Nutrition Research Centre, Northumbria University. 2016 Feb; 8(2): 68. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4772032/

24. Vitamins and Minerals for Energy, Fatigue and Cognition: A Narrative Review of the Biochemical and Clinical Evidence. Sanofi Consumer Healthcare. 2020 Jan; 12(1): 228. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7019700/

25. Vitamin B6. National Institutes of Health. https://ods.od.nih.gov/factsheets/VitaminB6-HealthProfessional/

26. Vitamin B12 in Health and Disease. Discipline of Nutrition and Metabolism, School of Molecular Bioscience, University of Sydney, NSW 2006, Australia. 2010 Mar; 2(3): 299–316. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3257642/

27. The effects of gelled konjac glucomannan fibre on appetite and energy intake in healthy individuals: a randomised cross-over trial. Clinical Nutrition and Risk Factor Modification Centre,St. Michael’s Hospital,Toronto,ON M5B 1W8,Canada. 2018 Jan;119(1):109-116. https://pubmed.ncbi.nlm.nih.gov/29202887/

28. Capsaicinoids supplementation decreases percent body fat and fat mass: adjustment using covariates in a post hoc analysis. Summit Analytical, LLC, 8354 Northfield Blvd., Building G, Suite 3700, Denver, CO 80238 USA. 2018 Aug. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6088424/

29. Current Understanding of Antiobesity Property of Capsaicin. Department of Pathobiology, Faculty of Science, Mahidol University, Bangkok, Thailand. 2017 Jan-Jun; 11(21): 23–26. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5414451/

30. Effects of Caffeine on Cognitive Performance, Mood, and Alertness in Sleep-Deprived Humans. Institute of Medicine (US) Committee on Military Nutrition Research; Marriott BM, editor. Washington (DC): National Academies Press (US); 1994. https://www.ncbi.nlm.nih.gov/books/NBK209050/

31. The Effect of Green Tea Extract on Fat Oxidation at Rest and during Exercise: Evidence of Efficacy and Proposed Mechanisms. Human Performance Laboratory, School of Sport and Exercise Sciences, University of Birmingham, Edgbaston, UK. 2013 Mar; 4(2): 129–140. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3649093/

32. Chromium and Insulin Resistance. University of California, San Francisco. 2011 July. https://clinicaltrials.gov/ct2/show/NCT00846248.

33. Effects of zinc supplementation on obesity: study protocol for a randomized controlled clinical trial. Institute of Health and Biomedical Innovation, Faculty of Health, Queensland University of Technology, Brisbane, QLD Australia. 2016; 17: 534. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5097376/

34. Chlorogenic Acids from Green Coffee Extract are Highly Bioavailable in Humans. Journal of Nutrition 2009 Jan; 138(12):2309-15. https://www.researchgate.net/publication/

35. The Effect of Konjac Glucomannan Fibre Gel on Satiety and Energy Intake. Fei Au-Yeung, 2016. https://www.semanticscholar.org/paper/The-Effect-of-Konjac-Glucomannan-Fibre-Gel-on-and-Au-Yeung/17b68898372a0bd97e1e690db698f179a66b087f

36. Gender-related Differences in Food Craving and Obesity. Department of Psychology, Yale University. 2016 Jun; 89(2): 161–173. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4918881/

37. Effect of Choline Supplementation on Rapid Weight Loss and Biochemical Variables Among Female Taekwondo and Judo Athletes. Faculty of Physical Education, Zagazig University, Egypt. 2014 Mar 27; 40: 77–82. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4096089/

38. Neuroprotective Actions of Dietary Choline. Department of Pathology and Laboratory Medicine, Boston University School of Medicine, 72 East Concord Street, Boston, MA 02118, USA; ude.ub@kcalsb (B.E.S.); ude.ub@ttollemt (T.J.M.) 2017 Aug; 9(8): 815. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5579609/

39. Vitamin B12 Supplementation in Treating Major Depressive Disorder: A Randomized Controlled Trial. Department of Psychiatry and Medicine (Neurology), Aga Khan University, Karachi, Pakistan. 2013 Nov; 7: 44–48. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3856388/

40. Long-term effects of Garcinia cambogia/Glucomannan on weight loss in people with obesity, PLIN4, FTO and Trp64Arg polymorphisms. Department of Morphological Sciences, School of Medicine, University of Córdoba, Avenida de Menéndez Pidal s/n, 14071 Córdoba, Spain. 2018 Jan; 18: 26. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5781311/

41. Eight weeks of supplementation with a multi-ingredient weight loss product enhances body composition, reduces hip and waist girth, and increases energy levels in overweight men and women. The Center for Applied Health Sciences, 4302 Allen Road, STE 120, Stow, OH, 44224, USA. 2013 Apr. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3639826/

42. Circadian Clocks and Metabolism. Department of Medicine, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7-107, Chicago, IL 60611, USA. 2014 July; (217): 127–155. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4089089/

43. Daily ingestion of grains of paradise (Aframomum melegueta) extract increases whole-body energy expenditure and decreases visceral fat in humans. Department of Nutrition, School of Nursing and Nutrition, Tenshi Collage. 2014;60(1):22-7. https://pubmed.ncbi.nlm.nih.gov/24759256/

44. Saffron: A Natural Potent Antioxidant as a Promising Anti-Obesity Drug. Department of Nutrition and Dietetics, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia. 2013 Dec; 2(4): 293–308. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4665515/

45. 5-HTP efficacy and contraindications. Clinical Research, NeuroResearch Clinics, Inc, Cape Coral. 2012 July; 8: 323–328. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3415362/