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Do Fat Burners Work? (The Science-Based Truth Revealed)

Isaac Robertson
Published by Isaac Robertson | Co-Founder & Chief Editor
Last updated: August 15, 2023
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The fitness world evolves every day because people strive to keep fit. Recently, fat burners have been introduced, which are perceived to help people shed some unwanted weight. This has led to the question if the fat burners actually work or if they are just a scam.

Understand that fat burners trigger the metabolic reaction, which burns stored fat and is used as fuel for the body. The metabolic processes are thermogenesis and lipolysis.

Quick Summary

  • Fat burners work if you take low calories and increase your workout routine.
  • Fat burners work by triggering metabolic processes, namely thermogenesis, and lipolysis, which burn stored fat.
  • Fat burners have natural ingredients which have scientifically been proven to burn fat, like green tea extract.
  • L-carnitine in fat burners products increase an individual's metabolism rate, increasing the fat being burnt.

How Do Fat Burners Work?

Fat burners work by triggering metabolic processes in the body that help the body to source fuel from stored body fat and also inhibit fat absorption.

Generally speaking, these metabolic processes can be split into 2 categories:


1. Thermogenesis

Two runners working on fat burners

Thermogenic fat burning processes involve burning calories to produce energy in the form of heat. (1)

Your body does this even when resting to maintain constant body temperature.

Exercise also triggers this fat metabolism process, but you can further boost thermogenesis with fat burners.

As a result, you can achieve an increase in weight loss when it is combined with a healthy diet. Basically, thermogenesis can be maximized through a combination of net negative calorie intake, exercise, and supplements.

2. Lipolysis

This process is a bit more complicated but don’t worry, I won’t bore you with a physiology lecture. Essentially, this is your body’s fat metabolism that breaks dietary and stored fat down into glycerol and free fatty acids.

Your body’s cells use these to generate energy, and supplements can trigger this outcome by boosting certain hormones, including ghrelin, epinephrine, and norepinephrine. The result is an increase in fat loss.

The important thing to note though is that these are not magic pills that will help someone with an obese body composition to lose some weight.

They have to be combined with a healthy diet and a strict workout routine to show any outcome at all.

Common Ingredients Found In Fat Burners

spoons and bowls of raw ingredients

While all dietary supplements for weight loss work with their own special blends of ingredients, there are certain nutritional sources that are quite common.

The first ones I want to highlight are the foods you can take in a natural way.

1. Natural Food Sources

Fortunately, mother nature has provided quite a few sources that you can easily add to your diet plan.

Either follow the below steps or look for these elements in fat burning supplements.


cup of coffee being poured

Most people rely on some coffee in the morning to get going, but did you know that caffeine can actually help with your efforts to lose weight?

Several clinical studies have been conducted on the metabolic impacts, and the evidence is clear that it has a thermic effect.

Results have shown that relatively small caffeine boosts can elevate energy use by 16% for a 2-hour period.

Now, before you think that you can just gulp down extra cups of coffee with a fat burner, the effect does wear off as your body becomes used to it.

It’s a great stimulant to take before you head to the gym, but don’t overdo it. Also consider some caffeine-free fat burners if you get too jittery with caffeine.

Green Tea Extract

green tea extract with raw ingredients

Green tea extract is basically a concentrated form of green tea commonly found in homemade fat burners.

If you like this type of tea, then you can elevate your consumption, but the taste isn’t that appealing to many people.

It also helps to suppress your appetite that's why it is also a must have for night time fat burner.

Taking it in the form of pills or powder will give you a boost in caffeine and a polyphenol called epigallocatechin gallate.

Combined, these two amplify the fat burning outcome and increase thermogenesis at the same time.

Most supplements available today, especially vegan fat burners, contain green tea extract not just for fat reduction, but it’s also a powerful antioxidant. (2) This makes it ideal for helping to flush out unwanted toxins at the same time.


raw turmeric that's turn to powder

Turmeric contains an antioxidant called curcumin, and this has been tested in several clinical studies to identify its usefulness in treating obesity. It works in two supporting ways.

First, it triggers thermogenic fat burning processes that essentially elevate your body temperature by burning more fuel, i.e., fat.

Secondly, it helps the gallbladder to produce more bile that makes the breaking down of dietary fat more efficient.

Adding this to your diet is actually quite simple, as you can add the spice to your main meal or take it in the form of a tea.


Cinnamon sticks grinded up

For most people, this is just a fancy spice with a unique flavor that works really well with those completely unhealthy buns.

Yes, absolutely delicious, but there is a little bit more to the cinnamon story. Researchers have found that the essential oil called cinnamaldehyde that is behind this flavor, actually has some thermogenic effects.

Basically, it’s going to turn up your body heat a little, and in doing so, it will burn some body fat for energy.

One option is to add a teaspoon throughout the day to your green tea or snacks.


cloves of garlic

Yes, for most people the smell is going to be just too bad, but others love the taste it brings to meals.

It’s certainly something you want to moderate to avoid living in isolation, but garlic triggers very similar processes to cinnamon.

Weight loss can be increased with relatively small amounts of garlic extract, which has less of a bad smell to it when mixed into pills and powders. (3)

Ideally, you should take this in raw form by adding some to your evening meal. This will have the added benefit of acting as one of the best appetite suppressants, so you avoid waking up starving.

Here's an interesting video from Chef Ricardo on how you can use garlic for weight loss.


roots from ginger

This is another completely underrated wonder of nature that is so easy to add to your diet.

Studies have proven that obese men reacted very positively to the regular intake of ginger in their diet.

Simply add some sliced ginger to boiling water and let it steep for 12 hours and then just drink it like a tonic or add it to your smoothies.

Just like the garlic and cinnamon, it will boost thermogenesis to help you lose weight through fat burning.

There is also some anecdotal evidence that combining all 3 on a daily basis amplifies the results.

Soluble Fiber

various bowls of grains with fiber

Fiber is often something that people don’t consume enough of.

Some people just look at the negative side of the carbs it usually contains, but that ignores the fact that it practically passes through your system undigested.

The nutritional value comes from the way it supports your digestive system by slowing things down to ensure more nutrients are absorbed.

Some early-stage studies have revealed a direct link between soluble fiber and metabolic rates that lead to faster weight loss, independent of other factors.

Beans and green veggies are the best sources of fiber, but you can also buy it in powdered form to give your digestion a helping hand.


raw yohimbine

This is one of the well kept Western African secrets that has become increasingly more available in the USA.

While its intended use is an aphrodisiac, there has been one very interesting study that revealed its results on fat metabolism.

By giving soccer players small doses, researchers were able to note a 2.2% decrease in BMI, which is not insignificant, considering that these players would already be very fit.

This does make it a very interesting product to top athletes and bodybuilders with any cutting phases they are going through.

It isn’t something you’ll find in supermarkets, but if you check out a local whole or health food store, you’ll be able to pick some up quite easily.

Dosages of 0.2mg/kg bodyweight have been successfully used to increase fat burning without significant implications on cardiovascular parameters like heart rate and blood pressure.
- Kamal Patel, Co-founder, and Director of

Now let’s shift our attention to elements that are a bit more difficult to get through food.

2. Concentrated Supplements

The above natural ingredients are easy to add to your eating habit, but there are some things that can be a bit more difficult to get enough of.

This is mainly because they are usually only contained in small amounts, and you’d have to eat a lot of them to get any result.

That’s why these types of fat burning nutrition elements are best sourced through pills or powders where they are contained in concentrated form.


pill bottle of l-carnitine

L-carnitine in fat burners has a direct impact on your metabolism and its ability to process fat. (4)

The way it works is by helping to transport fatty acids to cells where they are converted into raw energy.

Basically, the more of this stuff you can take, the faster your body can process stored fat.

Many athletes like taking it as part of pre-workout shakes as it reduces the dependence on carbs for energy.

However, it’s also a great product to have on your list to help with a cutting phase or just to lose weight.

You’ll find a lot of pre and post workout products will contain it, so always look out for it on labels.

Conjugated Linoleic Acid

Conjugated-Linoleic-Acid for weight loss

Conjugated Linoleic Acid (let’s just call it CLA), is a slightly modified form of Omega-6 and a substance that the body cannot produce by itself.

For a long time, it was mainly recommended for its antioxidant and immune-boosting effects.

But, in recent years it’s been heavily promoted for fat reduction and muscle retention impacts.

Most cutting stacks for bodybuilders will contain this in significant amounts as it also has very few side effects.


Jar of l-tyrosine powder

This is another increasingly common element in many bodybuilding products and stacks.

The main effect it has is increasing the production of adrenaline and noradrenaline.

As the levels of these neurotransmitters go up, your heart rate and temperature increase as well.

It won’t give you a massive adrenaline rush like a moment of fear would, but it’s enough to increase metabolic activity and thereby fat oxidation.

When you add the fact that it helps to reduce appetite, you get a two-pronged approach by burning fat and reducing food intake.

Doesn’t get much better than that.


grapefruit cut up

This is a substance that is extracted from the peel of many citrus fruits, including lemons, oranges, and grapefruit.

This makes it rather difficult to consume in natural form, as eating the peel is not exactly something you’ll look forward to.

A study from 2014 revealed that taking just 900 mg per day boosted the metabolism of overweight test subjects resulting in a loss of abdominal fat.

It is still a bit of a newcomer, and there aren’t that many products available, so make sure you look out for it on labels.

With all these ingredients, you’re probably wondering how you’ll get the best results.

How Do You Get The Most Out Of Fat Burners?

You get the most out of fat burners by combining them with an intense exercise and diet routine. If you follow this, then the answer to the question "Do Fat Burners Work?" is definitely - YES.

I cannot stress too much how important your food is when it comes to getting to your fitness goals. But first, find out if you are a sugar burner or a fat burner type.

Did you ever increase fat around your waist despite going to the gym?

Chances are you got these results because your eating habit was still full of crap.

Fixing that is the first thing you need to do, and after that, you can focus on maximizing your fat oxidation through a couple of simple tips.

1. Minimize Cardio

A man running with a cross over him

Cardio is great for your heart and vascular system, but it simply won’t give you the best results.

For the weeks you are taking fat burners, you have to up your game and hit the gym hard, by increasing the weights and reducing the reps in your workouts.

And rather than going for a leisurely 30-minute run, alternate between 30-second sprints and jogs.

This will drain your carb reserves, and you will start burning fat more effectively when running.

This might surprise most people, but when you want to get rid of fat, then you have to increase your energy expenditure and burn more calories.

2. Don’t Rely On One Product

various fat burning products

The unfortunate thing is that your body will get used to the stimulating and metabolic impacts and simply start responding less to them.

That’s why I always recommend that people switch between the above-mentioned options on a regular basis.

It doesn’t have to be a daily change, but if you change things around every few weeks it will have a very positive outcome on your goals.

When you’re looking at supplementing your meals, it’s just as important to pick a couple of reliable products to do the same thing.

Related Articles:

3. Avoid High Doses Of Stimulants

stimulant pills spilled on a table

While caffeine will provide significant benefits in reducing your BMI, these types of stimulants compared to stimulant free options can cause some unwanted problems.

And many people don’t keep track of all the stimulants they take, which just adds to the problem.

If your pre-workout, fat burner, morning coffee and evening green tea aren’t added up correctly, then you could quickly find yourself with jitters and a real difficulty getting to sleep at night time.

The easiest way to avoid this is by keeping a food journal and adding it up on a regular basis.

Also Read: Which one is better? Leanbean or Instant Knockout?


4. Plan Regular Off Cycles

man sitting on a bench at the gym

If you look at the training plans of professional bodybuilders and athletes, you will notice that they are never in a constant fat loss mode.

They might spend several weeks cutting in preparation for a competition, but once this is over, they will likely increase fat levels again.

The main reason is that a minimum amount of fat in the body is vital to a healthy immune and digestive system.

But even if you’re not at the extreme edge of BMI, it’s good to take regular breaks to avoid becoming immune to metabolic boosters.

5. Safe Weight Loss Goals

Unless you’re morbidly obese with imminent health risks, aiming for 2 to 3 pounds per week is more than enough.

I have seen it with many clients that went for higher rates, only to achieve worse results in the long-run. Constantly achieving lower goals is far more motivating and will help you adjust to lifestyle changes you’re making.

When it comes to reducing body fat, the general rule is that slow and steady brings the best results.

Fat Burner Side Effects

woman in bed with pillow over her head

If you stick to recommended doses that are printed on the labels, then negative side effects will generally be very limited.

In some cases, food allergies and intolerances are the underlying cause, and it may take some experimenting to find a suitable product.

Here are a few danger signs to look out for with fat burners, and if you notice any of these, then take a break immediately:

  • Nausea
  • Constipation
  • Headaches
  • Jitters
  • Insomnia

Many people tend to just pay attention to their weight loss while taking these types of products, but ignoring changes in your body can be more of a hindrance than you might think.

Not only will it reduce your motivation, but the way your digestive system and metabolism reacts can cause the exact opposite results you’re looking for.

The most common complaints include nausea, constipation, abdominal pain, and headache. What’s more, these supplements may lead to a slight increase in blood pressure
- Erica Julson, Registered Dietitian

Frequently Asked Questions

various brands of different fat burners

Is it safe to take fat burners?

Yes, it is safe to take fat burners as long as you stick to the recommended dose. Most products are available as pills or powder with very clear guidance on how much to take. Stick to this, and you’ll be doing just fine.

What is a thermogenic fat burner?

A thermogenic fat burner causes your body to increase its body temperature by burning more calories. If you’re taking in a net negative amount of calories, this will mean that fat oxidation will target those stubborn flabby areas you want to get rid of.

Is apple cider vinegar a fat burner?

Yes, apple cider vinegar is a proven fat burner and is often promoted by dieticians as an effective way to reduce belly fat. It’s also very easy to add a couple of tablespoons to your food every day. (5)

When should you take fat burners?

Ideally, you should take fat burners several times a day to spread the action out for a maximum fat loss. Before your workout and HIIT sessions is also recommended, as this can really elevate your metabolic rate.

Does coffee burn fat?

Yes, coffee helps to burn fat, or more precisely, the caffeine contained in it does. If you don’t like coffee, then green tea is another option that will help with fat loss. It’s less potent, but still a perfectly suitable option.

So, Do Fat Burners Work?

Yes, fat burners work if they are combined with a healthy diet and a stringent exercise routine.

If you’re significantly overweight and not willing to put in the effort and work that comes with a complete lifestyle change, then you will never get from flabby to fit.

Check out our product guides to make sure you don’t end up wasting your time and money on things that don’t work:

Weight loss is not an easy task, but with the right attitude and a bit of a helping hand from proven ingredients and products, you can set yourself up for success.

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