Protein World Fat Metaboliser Review 2023

Reviewed by Melissa Mitri, MS, RD

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protein world fat metaboliser review

About The Brand

Protein World was founded in 2012 by the visionary CEO Seth Arjun. One of their most renowned products is a fat burner called Protein World Fat Metaboliser.

After seeing a market need for high-quality sports nutrition products, Seth sought to integrate sports nutrition and medications and make them broadly accessible to the general public. They have expanded globally since then and now service 74 countries, such as Australia, the United States, the United Arab Emirates, and continental Europe.

Protein World is based in the UK and has developed various supplements catering to different needs.

What Is Protein World Fat Metaboliser?

These diet pills are designed to assist you in losing extra body fat and boosting your metabolism. According to the official Protein World website, these pills increase your overall metabolic activity. In addition, its ingredients are designed to lower cholesterol and boost energy for exercise.

The manufacturer recommends that the user combines the Fat Metaboliser with the Slender Blend supplement, also made by Protein World, for the best results.

Does It Really Work?

The Protein World Fat Metaboliser aims to speed up the body’s ability to metabolize fat.

This product also contains minerals and vitamins designed to lessen workout tiredness so you can train harder and longer. Additionally, the combination of ingredients in the product, such as green tea and anhydrous caffeine, is said to energize you and speed up the body’s metabolism of fats.

This product ranks among the most affordable fat burners available, possibly because it is only one of several products produced by this manufacturer. In looking at the product, it was never intended to contend against some of the more expensive standalone fat burners.


  • Contains caffeine, which may boost metabolism.
  • Contains great tea, which may support weight loss.
  • Improves focus
  • Energy-boosting ability
  • Effective natural fat burner
  • Natural ingredients
  • Inexpensive fat burner


  • Missing key ingredients
  • Has to be combined with other products and a balanced diet
  • Geared towards women
  • Not appropriate for caffeine-sensitive individuals

Feature Product & Coupon

protein world fat metaboliser review

Best Reputation

Protein World Fat Metaboliser

  • A fat-burning supplement
  • Increase metabolic rate
  • Boosting energy levels
  • Safe and Natural Ingredients
  • Made specifically for women
  • Can improve focus and concentration
  • Can be used with other supplements or workout regimens
  • Very affordable

Protein World Fat Metaboliser Ingredients

Looking at the ingredients list of the Protein World Fat Mateboliser capsules, you’ll notice that it does not include any proprietary blends. Also, each substance has a precise dose quantity, removing the guesswork in determining the combination. This is beneficial as many other weight loss supplements do not clearly list the dosages of ingredients on the label.

The instructions are to take two capsules twice a day.  Each capsule contains 2.8 milligrams (mg) of Vitamin B6, which is 200% more than the recommended intake amount. Luckily, there is nothing to worry about since Vitamin B6 has no side effects, even when taken in large quantities. 

protein world fat metaboliser ingredients

This product is affordable compared to others on the market. In addition, it is explicitly geared toward helping women burn fat and lose weight.

While it does not have all the essential ingredients (such as glucomannan, green coffee, and others) that one has come to expect in a fat-burning supplement, it still contains some.

We think if one wants to get better results using the product, they should combine it with others that contain better ingredients like glucomannan and green coffee or add it as part of their pre-workout supplement.

Caffeine Anhydrous

Caffeine, a common and of the best natural stimulant ingredients in most marketed fat burners, is among Protein World Fat Metaboliser’s main ingredients. Caffeine aids in the movement of fat from adipose (fat) issues in the body. Additionally, it can increase the pace at which fat is metabolized. Caffeine also increases the metabolic rate while resting by 3% to 11%, as per research[1]. This increases the pace at which the body burns calories.

Fat Metaboliser has 200 milligrams of caffeine, roughly comparable to 2 coffee cups. This is quite average for a supplement for burning fat, but remember that this amount is for two pills only, and the manufacturer suggests ultimately taking four capsules each day.

For some who are sensitive, this amount of caffeine may be too much for them to tolerate.

Green Tea Extract

Several studies[2] show that green tea’s catechins and caffeine improve the metabolic rate by increasing the concentration of hormones such as norepinephrine that burn fat. It also helps in firing off thermogenesis. However, you must consume or take large quantities to enjoy its possible weight loss benefits.


This is a nonessential amino acid that the human body produces from phenylalanine. It is crucial in making neurotransmitters in the brain. Despite reports that it can increase metabolism, there is no scientific proof that L-Tyrosine aids in weight reduction.

However, some research[3] has indicated that when used with caffeine-containing weight loss products, it may help in appetite suppression.

Whether or not it achieves the latter is debatable; several well-established compounds are far superior to L-Tyrosine as an appetite suppressant. One of these is the dietary fiber glucomannan.

Guarana Extract

The climber plant guarana originates in the Amazon Basin’s rainforests. According to studies[4], guarana seeds contain twice as much caffeine as coffee seeds. Compared to coffee seeds, which only contain 1% caffeine, the seeds of guarana have a caffeine content of 2-4%.

While the FDA has not approved the use of the extract for weight loss, it is approved for use as a food additive.

The amount of guarana extract in Fat Metaboliser is 150 mg, which is higher than the 50 mg to 100 mg a day advised by physicians and nutritionists, mainly when you take into account the other sources of caffeine in this product.

Yerba Mate Powder

Protein World’s Fat Metaboliser includes caffeine from 4 primary sources, including guarana (22% caffeine), green tea, Yerba Mate, and pure caffeine anhydrous. This can pack a strong stimulant punch when you’re not accustomed to it.

Although the study on Yerba Mate’s capacity to suppress hunger and burn fat is still preliminary, it is advertised for these effects despite having less caffeine than a coffee or green tea mug. Contrary to pure caffeine, Yerba Mate has not been associated with any specific increases in metabolic rate.

Although the study[5] on Yerba Mate’s capacity to suppress hunger and burn fat is still preliminary, it is advertised for these effects despite having less caffeine than a coffee or green tea mug. Contrary to pure caffeine, Yerba Mate has not been associated with any specific increases in metabolic rate.

The possibility of Yerba Mate treating obesity[6] has generated a lot of interest. However, this study was conducted on animals and has yet to be confirmed in human clinical studies.


Choline[7] is an essential nutrient present in food and supplements. It helps the human body metabolize fat more efficiently, leading to satiety. So, a person will require fewer calories and thus help with weight loss. While it isn’t as powerful as other conventional fat-burning substances like green tea, choline can help your body eliminate more fats than usual at your regular metabolic rate.

Choline appears less susceptible to harmful effects than certain substances on the market. The role it plays in breaking down fat can prevent future body weight and help your current weight loss efforts.

Choline is also a powerful nootropic[8], a nutrient that supports brain health. Because the body can only produce a tiny quantity, the remainder must be obtained by food or supplements.

Alpha Lipoic Acid

Alpha lipoic acid (ALA)[9] is not always considered critical in the fat-burning process. Still, it is said to increase the body’s rate of burning fat when consumed continuously over time. Given that the product only contains 100 mg of the 30 mg to 1,000 mg of ALA that is advised for daily consumption, it is unlikely to have any significant effect.

Cayenne Powder

Due to its active component capsaicin,  cayenne pepper has been found to reduce cravings, suppress appetite, and burn calories. Eating cayenne pepper may increase metabolism for up to 30 minutes,  according to a research study[10] from 2003.

It is a fantastic option for thermogenesis and appetite suppression, and Protein World Fat Metaboliser contains 50 mg. It could be quite effective alongside more potent fat-burning substances. However, the quantity of cayenne pepper may have been raised because the supplement lacks enough fat-burning ingredients for the product to be a stand-alone fat burner.

Alternatives To Protein World Fat Metaboliser

NamePhenQLeanBeanInstant Knockout
ProsEffective in burning fat.
It improves energy levels.
It enhances overall health.
An effective appetite suppressant.
A great weight loss supplement
Can be combined with other products or work out regimens for better results.
Use natural and safe ingredients
Burn fat
Promotes weight loss
A good appetite suppressant.
ConsHigh concentration of caffeineMade specifically for womenPricier
Full reviewPhenQ Review LeanBean Review Instant Knockout Review

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Health Benefits Of Protein World Fat Metaboliser

Protein World Fat Metaboliser Pills may assist you in shedding pounds by accelerating your body’s metabolism and helping with fat breakdown. They are naturally rich in vitamins, including vitamins B12 and B6, which can fuel your body when trying to lose weight.

The high caffeine content in the product can help boost the energy levels in your body. This is something that can be very useful, especially for people that are looking to work out. Caffeine can also help improve your focus and concentration, thus improving your productivity level.

Potential Side Effects

The majority of the ingredients in this product are safe to ingest in any sensible amount; however, the primary issue here is the high concentration of stimulants such as caffeine. While caffeine is beneficial in moderation, there is too much of it in the Protein World fat Metaboliser.

Some individuals may have adverse effects like nausea, jitters, anxiety, and the need to use the restroom more frequently. It also renders the product unfit for pregnant or nursing mothers.

None other components are predicted to have adverse effects at the prescribed dosage.


At the start of using the product, it is recommended that you take one diet pill two times a day. This is to gauge if your body is sensitive to the high caffeine levels contained in the substance.

If you do not have any unwanted effects, you can start taking the recommended dosage, which is two capsules, twice daily. The pills can be taken with a beverage, water, or as part of your meal.

If you notice any caffeine sensitivity due to your low caffeine tolerance, it is recommended that you seek medical advice immediately. Also, the product is not recommended for breastfeeding or pregnant mothers.

Lastly, anyone that is sensitive to caffeine should not take Protein World Fat Metaboliser.

Protein World Fat Metaboliser Review: What Do Real Users Say?

Have used for a few months now and when combined with a healthy diet I have lost around 2lb a week.


I used various fat burners, metabolisers and more in my life and this did not work at all. I did of course adapt my diet accordingly. Not sure if this was due to this product but my hair started falling out more when consuming these tablets and there was no real fat loss.


This is working really well with very little dietary changes, losing the llbs easily & no side effects. Feeling great, would recommend.


Final Thought

Protein World’s Fat Metaboliser is a fat burner geared toward women. While it has several ingredients that have been proven to help increase metabolic rate and promote fat burning, we feel it is missing some key elements.

Nonetheless, the manufacturer never meant for the product to be a standalone fat-burning supplement but rather be used in combination with other products on the market. Protein World recommends that consumers use the product with the Slender Blend if they want better results.

One thing that makes the product appealing is labeling it transparent, and one can see a list of all the ingredients used to make the capsules. Also, the ingredients are well known, and none have been known to cause any significant side effects.

Finally, the product is affordable, which makes it an excellent option for people looking to add it to their workout regimen or combine it with any other product on the market. Consult your dietitian for further guidance on product usage.

Frequently Asked Questions

Are there any side effects of Protein World Fat Metaboliser?

Because of the high caffeine levels, some users sensitive to the ingredients may experience adverse effects like nausea, jitters, anxiety, and the need to use the restroom more frequently.

Is it safe to consume Protein World Fat Metaboliser?

This product is safe for most people. However, the primary issue here is the high concentration of stimulants such as caffeine. While caffeine is beneficial in moderation, there is too much in the Protein World Fat Metaboliser. Some individuals may have adverse effects like nausea, jitters, anxiety, and the need to use the restroom more frequently.
Please note that pregnant or nursing mothers and people sensitive to caffeine should not use the product.

How to use Protein World Fat Metaboliser?

At the start of using the product, it is recommended that you take one capsule two times a day. If you do not notice any sensitivity or unwanted effects, you can start taking the recommended dosage, two capsules, twice daily. The pills can be taken with a beverage, water, or meal.

Is Protein World Fat Metaboliser FDA-approved?

No. However, the product is relatively safe since it contains well-known ingredients.

+ 10 sources

MIDSS adheres to strict procurement guidelines and relies on peer-reviewed studies, academic research institutes, and medical associations. We work mainly with peer-reviewed studies to ensure the accuracy of the information. We avoid the use of tertiary references. You can read about how we ensure the accuracy and timeliness of our content in our editorial process.

  1. Hoffman, J.R., Kang, J., Ratamess, N.A., Jennings, P.F., Mangine, G. and Faigenbaum, A.D. (2006). Thermogenic Effect from Nutritionally Enriched Coffee Consumption. Journal of the International Society of Sports Nutrition, [online] 3(1). doi:10.1186/1550-2783-3-1-35.
  2. Mousavi, A., Vafa, M., Neyestani, T., Khamseh, M. and Hoseini, F. (2013). The effects of green tea consumption on metabolic and anthropometric indices in patients with Type 2 diabetes. Journal of research in medical sciences : the official journal of Isfahan University of Medical Sciences, [online] 18(12), pp.1080–6. Available at:
  3. Belza, A., Frandsen, E. and Kondrup, J. (2006). Body fat loss achieved by stimulation of thermogenesis by a combination of bioactive food ingredients: a placebo-controlled, double-blind 8-week intervention in obese subjects. International Journal of Obesity, [online] 31(1), pp.121–130. doi:10.1038/sj.ijo.0803351.
  4. Moustakas, D., Mezzio, M., Rodriguez, B.R., Constable, M.A., Mulligan, M.E. and Voura, E.B. (2015). Guarana Provides Additional Stimulation over Caffeine Alone in the Planarian Model. PLOS ONE, [online] 10(4), p.e0123310. doi:10.1371/journal.pone.0123310.
  5. Alkhatib, A. and Atcheson, R. (2017). Yerba Maté (Ilex paraguariensis) Metabolic, Satiety, and Mood State Effects at Rest and during Prolonged Exercise. Nutrients, [online] 9(8), p.882. doi:10.3390/nu9080882.
  6. Kim, S.-Y., Oh, M.-R., Kim, M.-G., Chae, H.-J. and Chae, S.-W. (2015). Anti-obesity effects of Yerba Mate (Ilex Paraguariensis): a randomized, double-blind, placebo-controlled clinical trial. BMC Complementary and Alternative Medicine, [online] 15(1). doi:10.1186/s12906-015-0859-1.
  7. Elsawy, G., Abdelrahman, O. and Hamza, A. (2014). Effect of Choline Supplementation on Rapid Weight Loss and Biochemical Variables Among Female Taekwondo and Judo Athletes. Journal of Human Kinetics, [online] 40(1), pp.77–82. doi:10.2478/hukin-2014-0009.
  8. Tabassum, S., Haider, S., Ahmad, S., Madiha, S. and Parveen, T. (2017). Chronic choline supplementation improves cognitive and motor performance via modulating oxidative and neurochemical status in rats. Pharmacology Biochemistry and Behavior, [online] 159, pp.90–99. doi:10.1016/j.pbb.2017.05.011.
  9. Kucukgoncu, S., Zhou, E., Lucas, K.B. and Tek, C. (2017). Alpha-lipoic acid (ALA) as a supplementation for weight loss: results from a meta-analysis of randomized controlled trials. Obesity Reviews, [online] 18(5), pp.594–601. doi:10.1111/obr.12528.
  10. Chaiyata P;Puttadechakum S;Komindr S (2020). Effect of chili pepper (Capsicum frutescens) ingestion on plasma glucose response and metabolic rate in Thai women. Journal of the Medical Association of Thailand = Chotmaihet thangphaet, [online] 86(9). Available at:


Mitchelle Morgan is a health and wellness writer with over 10 years of experience. She holds a Master's in Communication. Her mission is to provide readers with information that helps them live a better lifestyle. All her work is backed by scientific evidence to ensure readers get valuable and actionable content.


Melissa Mitri, MS, RD
Medical Reviewer
Melissa Mitri is a Registered Dietitian-Nutritionist and Expert Health Writer with over 14 years of experience in the health and wellness industry. Melissa's specialties include weight management, women's health issues, and building sustainable healthy habits for life. As a nutrition professional who runs an evidence-based practice and provides written content for several brands, Melissa uses the latest unbiased scientific research to guide healthcare recommendations for her clients and the public.

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