Total Shape is a reader-supported site. Purchases made through links may earn a commission. Learn more.

What are the Pros & Cons of Fat Burners? (What to Expect)

Isaac Robertson
Published by Isaac Robertson
Fact checked by Donald Christman, BHSc FACT CHECKED
Last updated: April 25, 2023
We personally test every product featured in our reviews and guides. By ordering products anonymously and getting a group of independent testers, we are able to get first-hand experience and provide data-driven recommendations. Learn more.

Nowadays, everyone wants to find a shortcut to a lean, attractive fitness model figure, but only rare individuals are disciplined, patient, and dedicated to a healthy lifestyle.

So, no wonder people often become victims of omnipresent adverts for fat burners, promising rapid results with little work.

Popping up a pill is much easier than running, right?

Still, not all supplements are created equal. Some may even help suppress your appetite and lose weight.

Our expert team has done a thorough background check on thousands of diet pills’ significant pros and cons.

Scroll down and learn what to watch out for and what effects to expect before you fall for all those deceptive “miraculous instant results” claims and buy a product that’ll burn a hole in your wallet instead of excess blubber.

Quick Summary

  • Fat burners help manage food cravings, speed up weight loss, and boost an individual's energy levels.
  • These supplements can also improve your mental focus, and alertness.
  • Some fat burners are ineffective and you should be careful on the brand you purchase.

4 Fat Burner Pros

1. They Can Help Manage Food Cravings

woman pushing away a plate of sweets

Unhealthy nutritional choices,binge-eating, fat and carb cravings you often indulge in due to low blood sugar levels [1], hormonal imbalances, stress, negative emotions [2], and many other physiological and social factors may lead to weight gain, type 2 diabetes, cardiovascular disease, and other health risks.

Everyone who has ever tried to resist those cravings knows how challenging they are to control.

That’s why most fat burners contain appetite suppressants such as protein powder [3] or soluble fiber additives [4] that help you curb hunger cravings and prevent emotional binge-eating.

Such substances can increase satiety, prolong gastric emptying, slow glucose absorption, reduce leptin levels, suppress hunger-stimulating hormone ghrelin, etc., enabling you to skip snacks, reduce caloric intake [5], and lose or maintain weight without relying on your self-discipline only.

Some common ingredients in diet pills with these effects include:

  • Glucomannan
  • Coleus Forskohlii
  • Chromium
  • Beta-Glucans
  • Garcinia Cambogia and similar [6].

2. They Can Speed Up Weight Loss

man using a measuring tape on his bare stomach

Fat-burning supplements with thermogenic ingredients like Caffeine, Green Tea Extract, or Yohimbine can speed up fat loss by:

  • Boosting your carb and fat metabolism
  • Blocking fat absorption and accumulation
  • Increasing fat oxidation and energy expenditure during exercise [7]
  • Stimulating the release of neurotransmitters (like norepinephrine and adrenaline) that trigger glucose release to burn fat reserves from your adipose tissue

Some studies have reported that Caffeine can increase your metabolism by 3-11% [8] [9], making your body use fat more efficiently to produce energy and supporting weight loss [10].

Also, Green Tea contains Catechin proven to trigger thermogenesis and enhance metabolism when paired with caffeine [11] [12].

Then, Yohimbine (from Pausinystalia Yohimbe) blocks alpha-2 adrenergic receptors, allowing adrenaline to stay in your body longer, burning fat to produce energy [13].

The fat-burning effects of some other similar compounds like L-Carnitine, Conjugated Linoleic Acid, forskolin, kelp, fucoxanthin, etc. are controversial as their safety is questionable [14].

Of course, thermogenic fat-burning supplements may help you lose weight faster if combined with a balanced calorie-restricted diet and regular physical activity.

3. They Increase Your Energy Levels

happy man in a sweater showing off his biceps

Many fat-burning pills, especially thermogenics, contain additional ingredients with stimulant properties intended to provide consumers with an energy boost.

Their effects are similar to those you can experience after taking an energy drink like guarana or coffee.

Some such compounds increase your blood flow, helping deliver more oxygen and nutrients to your muscles during a workout, supporting the oxidation of fatty acids critical for fat loss, and even improving your sexual function.

By torching the stored fatty acids, these ingredients increase energy production on a cellular level from glucose and fat (ATP).

Taking a fat burner with Caffeine, Green Tea, and similar stimulative substances shortly before your workouts can provide you with an extra kick of energy so that you keep moving in the gym and torch more calories when you exercise.

Also, such fat burners are supposed to improve your endurance and reduce fatigue, enabling you to train harder not only for a short period but in the long term so that you can burn more body fat (in conjunction with a low-calorie diet).

The trick is that the energy you get from highly potent stimulants is difficult to control and often comes with jitters, restlessness, anxiety, and other possible side effects if your body doesn’t take advantage of it.

That’s because these substances usually pick you up instantly and make you crash eventually.

4. They Improve Your Mental Alertness and Focus

young female meditating in peace

So many people often feel sluggish, fatigued, and face mood swings, irritability, and similar behavior changes when they adopt a calorie-restricted diet and start with regular grueling workouts.

It’s hard to get your butt to the gym if you don’t see any results in weeks, isn’t it?

To make people feel better and continue their demanding weight loss process until they reach their fitness goals, many companies put stimulative nootropic ingredients into their fat burners to boost users’ mental focus, alertness, feeling of vigor, memory, and motivation.

That’s how they attempt to empower you to find a good reason to stick to your diet and exercise plan and melt away body fat even when you don’t feel like eating healthy and working out.

4 Fat Burner Cons

1. Choosing a Fat Burner is Challenging

man frustrated over bottle of pills in front of him

It may be tricky to choose the right supplement that suits your needs, goals, and budget to help you lose weight, as the selection has recently become overwhelming.

You can find hundreds of more or less expensive fat burners on the market boasting about the effectiveness of their unique formula, promising their consumers quick weight loss alongside other overall health benefits.

I’d steer clear of all the weight loss supplement manufacturers that promise wonders overnight because the market’s been oversaturated with fraud.

That’s because The Food and Drug Administration (FDA) doesn’t regulate dietary supplements or study their ingredients [15], meaning that the manufacturer can put almost anything, including suspicious chemicals, in their products (which brings us to more other cons).

2. Some May be Completely Ineffective

woman upset with her thumbs down holding a sachet of pills

Many overweight people expect fat burners to burn fat on their own while they sleep without any effort to break their bad dietary habits and change daily activities.

That’s simply not going to happen.

Studies have found that most fat burners burn no more than 50 calories per day if users lead a sedentary life.

That’s not even close to a can of soda that contains approximately 150 calories.

Even worse:

Some fat-burning blends contain protein powder that comes with a particular amount of calories. As a result, you may easily take in as many calories as the supplement can burn on its own without changing your diet and exercise habits.

“The only natural way to lose weight is to burn more calories than you take in.”

- James P. Smith, M.D.

Although the majority of fat burners claim to contain highly potent, effective, science-backed compounds that burn fat rapidly, if you take a closer look at a product label or company websites, you’ll see a note that says: “These statements are not approved by the FDA.”

It means you never know if these products do and contain exactly what the companies claim.

Also Read: Are Fat Burners Dangerous

3. Some Ingredients Are Addictive

woman hiding while taking pills

Research has found that some fat-burning supplements contain addictive ingredients.

And we’re not talking about Caffeine only, but stimulant medications like amphetamines, psychotropic drugs like cannabis, or similar drug-like components and controlled substances.

Jayson Hunter, registered dietitian and founder of JayLab Pro, adds that stimulant-based formulas can be very popular because many people feel the increase in body temperature or energy which gives them this feeling that it is working.

While stimulant-based formulas are generally safe for most people, they can cause unwanted side effects in certain individuals that may be sensitive to stimulants.

Their regular, long-term consumption is dangerous for your health, especially if you’re taking stimulants in high doses.

Also, you build up a tolerance over time and reach a plateau in losing weight.

So, most people opt for spending more money on stimulant-free natural fat burners and hope to avoid a health risk.

However, even herbal fat burners can be dangerous, particularly for people with high blood pressure, insomnia, anxiety, mental, and other health issues, as they can trigger heart attacks, acute liver failure, panic attacks, etc., [16] [17] [18].

It’s important to do thorough research and ensure the supplement you’re buying to help you burn fat contains only safe and effective ingredients.

4. Some Components Can Be Harmful

man holding his forehead in pain

The FDA has issued a warning for consumers [19] because many supplements use various, not always risk-free mechanisms and ingredient combos to stimulate your metabolism, reduce appetite, enhance lipolysis, burn fat, and stop its accumulation.

For instance, Ephedrine is the most common prohibited addictive chemical used in fat burners, which may cause a range of adverse reactions like dry mouth, headaches, irregular heart rate, seizures, etc.

Although most diet supplements typically contain ingredients that aren’t harmful when taken alone in small doses, the fact is that manufacturers don’t always list all the ingredients and specify their exact total amount on the label.

In addition, the companies aren’t required to get the FDA approval before they produce and put their over-the-counter supplements on the shelves to sell them.

It means that even if you check the bottle, you can never know for sure what you’re consuming in those supplement mixtures, which may be risky if you’re allergic, oversensitive, pregnant, or not 100% healthy.

Among various other ingredients like Citrus Aurantium and Synephrine, Caffeine is one of the most common compounds in fat burners, potentially leading to a range of mild to dangerous side effects because it’s easy to overdose accidentally [20].

What Are the Side Effects of Taking Fat Burners?

The side effects of fat burners include:

  • Nausea
  • Diarrhea, constipation, and other stomach problems
  • Jitters 
  • Sleeplessness
  • Increased blood pressure
  • Stroke 
  • Various cardiovascular issues
  • Liver damage or failure
  • Nervousness, irritability, similar behavior changes 
  • Seizures, etc.

Wrap-Up: Pros and Cons of Fat Burner Supplements

Different fat burners work differently and have various advantages and disadvantages, depending on their formulation.

When used correctly - in the recommended doses over a short time, complemented with a healthy, restricted diet and regular exercise, most of them are harmless, with the benefits outweighing the risks.

Since the supplement market is unregulated, it’s advisable to be extra precautious when choosing the best product for yourself. Check out our list of quality fat burners for men and women:

Always read product reviews, talk to other product users, consult your physician, and compare all your options, weighing every pro and con before you begin using any fat burners or similar dietary supplements.

Please, share your experience with the fat burners and tell us if they have worked out for you.


Was this article helpful?

About The Author

You May Also Like

Write a Reply or Comment

Your email address will not be published. Required fields are marked *