Supplements Lifestyle

Do Fat Burners Work? A Detailed Guide to Fat Burner Supplements

what are fat burners

As you train hard and work towards that lean physique and long-lasting endurance, you may need help to push your body to work even harder.

Eating a healthy, balanced diet with the right nutrition will always assist in getting fit; however, sometimes you may look for other means to push your body just a little bit further.

Pre-workout supplements are helpful, but there are so many different kinds. If you are looking to burn fat while improving your workouts specifically, fat burners may be the right choice for you.

What exactly are fat burners, and how do they work? Thankfully, this guide will help you answer those burning questions.

What are Fat Burners?

Fat burners are supplements specifically aimed to excite your metabolism and increase its speed.

While they primarily target the metabolism, they also strive to reduce the amount of fat absorbed by the body to stimulate weight loss.

Fat burners are not precisely like pre-workout supplements, although fat burners can be included in pre-workout supplements. Pre-workout aims to improve your ability to perform during exercise, increasing the effects of training overall.

Fat burners specifically target the metabolism to enhance your body’s ability to target fat, especially when coupled with exercise.

How Do Fat Burners Work?

Fat burners are often referred to as thermogenic or thermogenic supplements.

To understand how fat burners work, we need to look at the kinds of fat in the body and what type of fat is being targeted by the fat burner. Then, we can see the two types of fat-burning processes occurring in the body.

The human body has two types of fat cells (also referred to as adipocytes or adipose): white fat cells and thermogenic fat cells. According to Trends in Genetics [1], white fat cells store energy and transmit hormones when the body sends nutritional signals.

On the other hand, thermogenic fat cells resist hypothermia and defend the body against obesity.


Thermogenic fat cells, which fat burners target, have been shown to “significantly include whole-body metabolism in humans.” Thermogenic means “to produce heat,” and it mainly applied to supplements that increase the metabolism through thermogenesis.

Thermogenesis is the creation of heat in human tissues that results in a rise in body temperature. In regard to fat cells, the production of heat takes place in adipose cells and breaks down the fat stored in those cells. By breaking down the fat in the cells, the stored fat is used to create heat.


Fat can also be burned through lipolysis. During this process, lipids or fats are broken down through hydrolysis. During hydrolysis, enzymes and water break down energy stored in fat cells into fatty acids that are used to fuel the body.

Therefore, fat burners aim to increase metabolism by having the body create energy by using existing stored energy to produce heat/energy. In essence, fat burners ask the body to burn more calories and fat by generating heat.

Fat Burners

What Types of Fat Burners are There?

There are several different types of fat burners. A few of them are related to the processes they undergo or stimulate in the body.


These are the fat burners that target the production of heat in the cells. This type specifically targets thermogenic fat cells instead of just white fat cells.


This type of fat burning supplement aims to boost metabolism without using caffeine. The ingredient caffeine may cause some individuals to crash after high levels of energy, or other individuals may simply not like the effect of caffeine on the body.

This type does not stimulate energy levels. Stimulant-free supplements still aim to improve metabolic rates, and they usually strive to enhance thermogenesis.

Appetite Suppressants

This type of supplement is designed to suppress or diminish your appetite. In doing so, you will avoid snacking or overeating. Some of these suppressants interact with hormones in the stomach or gut that make you feel hungry, others communicate with your brain to make you feel fuller after eating.

Many appetite suppressants have caffeine or extracts that offer a form of caffeine. This is due to the fact that caffeine is known to suppress appetites while improving levels of energy.

Carb Blockers

These are supplements that hinder carbs from being fully digested into the body. They do this by stopping enzymes from reaching the carbs and reacting with it. Since the carbs are not absorbed or not fully digested, they move through the intestines without providing calories or sugar to the body.

What Are the Ingredients?

Depending on the form, fat-burners can have different ingredients or can be combined with ingredients included in pre-workout supplements. There are a few common ingredients found in fat burners.


A vast majority of fat burners have some stimulant in them. Caffeine in these supplements attempts to prolong your focus, improve your mood, minimize fatigue, and increase your workout time. As a fat burner, caffeine can reduce hunger and, depending on the kind of
caffeine, improve calories burned.

The caffeine could be labeled as caffeine, but caffeine can come from extracts as well. The following extracts are used for caffeine in supplements. Some extracts have chemical properties that boost the metabolism, and some are considered to have antioxidant benefits as well


  • Green Tea
  • Yerba Mate
  • Geranium
  • Orange Extract
  • Cayenne Peppers
  • Coffee Bean Extract
  • Yohimbine

L-Carnitine (Tartrate)

L-Carnitine, or just Carnitine, is a substance that is usually formed in the body after eating meat or dairy.

The substance is aimed to burn fat and maintain health. Carnitine specifically intends to use fatty acids within the body to boost and expend energy.

L-Carnitine moves fatty acids into the mitochondria, which is the powerhouse of the cell. It is possible that this substance can help maintain or improve the health and function of your mitochondria.

Users should know that L-Carnitine is not a stimulant. Instead, it is an amino acid that targets the stored body fat. Interestingly, L-Carnitine can also help reduce muscle tenderness and soreness caused by working out. For some, it can even reduce recovery periods after strenuous exercising.


Some fat burners may include capsaicin. This can be found in chili pepper extract, and it is also used for pain relief.

Capsaicin specifically aims to reduce pain, reduce inflammation, and reduce nerve pain.

The ingredient does this by blocking or reducing signals sent by pain receptors and helps release endorphins or dopamine.


Chromium is a mineral that is naturally found in the body in low amounts.

Chromium has been shown to increase the effects of insulin, which directly interacts with carbohydrates, fat, and protein within the body.

Chromium has a “glucose tolerance factor,” which means that it helps to maintain healthy levels of glucose, or sugar, in the body. In fat burners, Chromium is intended to help the body regulate and use sugar and carbohydrates.

Do Fat Burners Work?

While studies are sparse or inconclusive regarding the effects of supplements or specific supplements overall, some of the ingredients in fat burners are proven to improve the metabolism and increase the amount of fat burned.

First and foremost, fat burners, like pre-workout supplements, can help improve the exercise you are already doing.

Some of the ingredients can help you maintain your focus and work out for more extended periods. This means you can work out longer, or at higher intensities, and see the benefits of doing so.

Fat burners can also improve thermogenesis or lipolysis, both of which are fat-burning processes of the body.

Some studies [2] have shown that “caffeine can increase energy expenditure (at rest) or fat oxidation (at rest and during low-intensity exercise).” Therefore, caffeine can help burn more fat by increasing the amount of energy you spend.

Supplements with green tea and green tea extracts have been proven to improve metabolic rates. Those who consume green tea or green tea extracts reduce the size of their waist and total fat.

Ingredients such as Forskolin and Fucoxanthin have been found to improve metabolic rates and fat-burning directly. Forskolin instigates lipolysis, meaning the body is burning and oxidizing fat at higher speeds. Fucoxanthin, which is also found in seaweed, helps to reduce white adipose tissue, meaning you become leaner more quickly.

Fat burners have been shown to work, but you always need to check the ingredients, know how they work and understand how your own body works.

Do fat burners really work?
Do fat burners really work?

Are Fat Burners Safe?

The safety of the fat burner is truly dependent upon the ingredients and the supplement’s use. Some fat burners have been taken off the market because of unsafe ingredients. However, many other ingredients have been found to be safe.

A study conducted in Food & Nutrition Research [3] shows that ingredients such as caffeine, green tea extract, and cayenne powder are proven to be safe. On the other hand, supplements with ephedrine can cause physical damage to individuals who are not considered healthy.

Therefore, it is essential to know your own physical health and the ingredients in your fat burners. Some ingredients are proven safe, but others may not be safe for consumption or your body.

Users of fat burners should also be aware that fat burners need to be used appropriately and within the specified dosage amounts. Simply, fat burners should be used carefully and intelligently. Misusing them can cause serious side effects.

Make sure to eat enough calories, especially if you are taking an appetite-suppressant. You always want to maintain a healthy diet while losing weight.

If your fat burner contains a stimulant, be careful of the other caffeine-rich foods you eat or drink. You want to be especially careful if you drink coffee in the morning or indulge in caffeinated sodas and beverages during the day. Having too much caffeine can affect your sleep and over-stimulant your body.

When used appropriately and within the recommended doses, fat burners are safe and effective.

Always be sure to check the labels and know what you are putting into your body.

Fat Burner Side Effects

There can be side effects when misused or used carelessly. Fat burner side effects can include:

  • Headaches
  • Tremors
  • Increased blood pressure
  • Insomnia
  • Nervousness
  • Abnormal heart rates
  • Stomach aches
  • Overheating / heat exhaustion
  • Dehydration

Fat Burner Side Effect Prevention

Users of fat burners need to track their weight loss closely. Losing weight too quickly may result in the slowing of the metabolism. This result stems from several reactions in the body.

First, the body starts to lose muscle, along with fat. Second, the body’s hormones may fall and signal the metabolic process to slow. Finally, the body is attempting to retain calories because it is afraid it may fall into a mode of starvation.

Additionally, be sure to track your nutrition. Users may fall into the trap of replacing meals with fat burners, or users may experience reduced appetite and not eat proper portions.

Unbalanced nutrition can lead to physical exhaustion, hair loss, hair thinning, and lowered immunity.

For those using stimulant-based fat burners, regulate intake. Excess amounts of caffeine can disrupt sleep cycles. Moreover, fat burners can cause excess sweating, overheating, and excess hydration. Be sure to drink plenty of fluids and take breaks when needed.

Always make sure to track any side effects that you experience. Fat burners react differently to different bodies. If you experience extreme or life-threatening side effects, seek medical attention immediately.

It is always a good idea to discuss with a medical professional whether fat burners are right for you, your body, and your lifestyle.


Do fat burners really work?

Fat burners have been shown to work, especially ones with Forskolin and green tea extract.

You need to be careful about what ingredients are in your fat burner, because some ingredients may not work well with your body.

When should I take fat burners?

The time you take your fat burner can depend on the type of supplement you take and what results you want it to have.

For appetite-suppressants, you may want to take this in the morning when you wake up, or you can take it when you are hungriest, such as 30 minutes to an hour before your meal.

If your supplement is aimed to give you energy and burn more fat during your workout, you can take a fat burner like a pre-workout supplement. This means you can take it 30-45 minutes before working out or training.

If you want to use the supplement as an energy booster during your day, you can take it when you need a pick-me-up, such as when you wake up or when you are tired mid-afternoon.

Some fat burners are especially designed for fasted training, and may be suitable for intermittent fasting. They usually do not contain caffeine or any stimulants and contain ingredients that help retain muscle mass.

Think about the results you want from your fat burner, and use this as a guide to decide the time you should take it.

Why should I take a fat burner?

Fat burners can help you boost your metabolism and burn more fat while exercising. They can help you become leaner by using your white fat cells and thermogenic fat cells. They can help regulate your appetite to maintain healthy portion sizes during meals or reduce snacking.

Taking a fat burner is your own choice, as you know your own body the best. Make sure to do your research and figure out if a fat burner is right for you. If so, double check the ingredients in the fat burners and know how they work.

Can you take fat burners on an empty stomach?

Some supplement labels will tell you to take your fat burner on an empty stomach. Taking the fat burner on an empty stomach will allow the supplement to be absorbed by the body quicker. However, use your supplement in a way that is most beneficial to you.

You can take the supplement on an empty stomach, but this is not required. Some people get sick when taking a fat burner on an empty stomach. If this is the case, you can eat something with your fat burner.

Does pre-workout burn fat?

Pre-workout is designed to help the body exercise for longer periods and at higher intensities. The pre-workout is not specifically designed to burn fat. Instead, pre-workout aims to improve exercise performance, which may result in burning more fat.

You should understand that fat burners do not directly burn fat either. Instead, fat burners encourage the body’s metabolism to burn fat stored in white fat cells and thermogenic fat cells. The body is stimulated by the fat burner and then burns more stored fat.

Fat burners

How can I reduce my tummy naturally?

Natural ways to reduce tummy of belly fat is to avoid sugary drinks, especially artificially flavored drinks. Eating more protein has been proven to help reduce belly fat. There are many natural foods to eat that help reduce stomach fat.

Exercise always helps to reduce a stomach, especially activities designed to target the stomach.

Crunches, including side crunches, twist crunches, and reverse crunches, are specifically designed to target the core and abdomen. Lunge twists are also great to target the midsection.

Any activity that involves a twist or a bend at the waist will most likely target the stomach area. The best way to reduce your tummy naturally is to maintain a healthy and balanced diet, as well as exercise regularly.

What foods help burn fat?

Foods higher in protein, such as Greek yogurt, can help burn fat. Quinoa is a great fat burning food.

Peppers also have ingredients that help boost metabolic rates. Green tea is a great drink alternative to sugary drinks.

Fruits such as watermelon, grapefruit, pears, apples, grapes, and blueberries are great snacks that help burn fat. Almonds are also a great snack to have that is easy to eat on the go.

Here is a quick list of foods that help burn fat:

  • Fruit: watermelon, grapefruit, pears, apples, grapes, and blueberries
  • Seafood: sardines, mackerel, herring, tuna, salmon, mussels, anchovies, trout, pollock
  • Nuts: Pistachios, almonds, walnuts
  • Drinks: green tea, green coffee, water, ginger teas, lemon water, carrot juice

What are natural fat burners?

Natural fat burners include caffeine, green tea extracts, some protein supplements, fiber supplements, and different herbs and spices. You can find some natural fat burners on the market that include these ingredients.

Do not forget that exercise is a natural fat burner, as well as some of the foods listed already.

Do nighttime fat burners work?

Nighttime fat burners work much differently than daytime fat burners.

Nighttime fat burners primarily work as an appetite suppressant. They can help curb cravings during the night. They then try to promote lipolysis while acting as a sleep aid. Fat burners may not work for everyone, and they are certainly aimed to treat the body differently than daytime fat burners.

Think about why you are using nighttime fat burners and what you want them to do. They are not a quick fix, and they should be used alongside a healthy diet and exercise.

Do fat burners make you lose muscle and/or lean muscle?

If you do not observe your body and supplement use, then you may lose weight too quickly. Some of the weight you lose could be muscle. A great way to combat unwanted muscle loss is to work on both losing fat and maintaining the muscle you have (or want to keep).

Bottom Line: The Truth About Fat Burners

Fat burners are only 70-80 percent of the work. Fat burners are not the first and final solution to fat burning, fitness, or weight loss. It is a supplement, which means that you use it to supplement your diet and exercise.

To burn fat, you need to eat a healthy, balanced diet, and you need to work the body through exercise or other activities. Nutrition and exercise are fundamental to maintain a healthy weight or to become physically fit.

Fat burners can help you in your goals of burning fat, but do not make it your only method to get lean and fit. Instead, think of a fat burner as a little boost to help you burn the fat you want gone.

Your goal should be to feel positive about yourself and your body while maintaining your health and fitness.



  1. Formation and activation of thermogenic fat –

  2. Fat burners: nutrition supplements that increase fat metabolism –

  3. Consuming a multi-ingredient thermogenic supplement for 28 days is apparently safe in healthy adults –


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Legwork Team

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