Taking steps toward weight loss is a big step, so two thumbs up from us.

We’ve written this guide to address two things that are probably at the front of your mind when researching the best fat burners: Do fat burners work, and how do fat burners work?

It’s important for you to feel safe and comfortable with the fat burning supplements you decide to take. After reading this guide you’ll have the peace of mind to know which ingredients are safe, as well as an understanding of how they work and where they come from.

We know there is no magic pill to lose weight, but there are scientifically-backed diet supplements that can burn fat, and supercharge your weight loss efforts.

What are fat burners?

Put simply, a fat burner is any compound that helps your body to burn fat more quickly than it would otherwise. The term also includes compounds that suppress appetite, reduce nutrient uptake, or increase energy: Three mechanisms that don’t burn fat directly, but can contribute meaningfully to weight loss.

Fat burners are supplements designed to give an extra boost to your weight loss efforts. They are best taken in conjunction with a healthy and balanced diet, a safe calorific deficit, and regular exercise, but keep in mind that they are not substitutes for those things.

This can be achieved by increasing your body’s metabolic rate (the speed at which energy is burned) or by increasing your body’s temperature (more energy is burned when you are hotter).

Increasing metabolic rate

Metabolism is the natural process through which your body maintains life. It involves all sorts of bodily processes, with three overarching aims:

• Converting food to energy.
• Converting food to building blocks for various parts of the body: Things like cell walls, blood cells, bone, and so on.
• Eliminating the waste products from these processes.

Your metabolic rate determines how quickly each of these things take place. A higher metabolic rate means faster metabolism, and that your body will break down foods and eliminate waste more quickly. More energy will be required to fuel a higher metabolism, and because fats are one of the fuels used to provide this energy, a higher metabolism means more fat is burned rather than being kept in your body.

Increasing your temperature

Interestingly it is the same chemical that makes food taste spicy that is involved in the reaction that increases your temperature, but more on that later.

As for the other fat burning mechanisms, the ones which don’t burn fat directly:

Suppressing appetite

Some fat burners work by helping you to feel full, and to not feel the need to eat as much as a result. Some achieve this by physically expanding in your stomach; others work with neurotransmitters in the brain to suppress your feelings of hunger.

Reduce nutrient uptake

By reducing or removing cravings, fat burners can help you to reduce the amount of food you eat. This, by extension, reduces nutrient uptake in the body. Eating fewer calories is an important part of maintaining a healthy caloric deficit, itself an important part of effective weight loss.

Increase energy

Some fat burning supplements help you to to do more exercise, by providing an energy boost. As we know, regular exercise is a vital part of any weight loss plan, and every little bit of extra energy helps with this.

It is important to do your own research and to understand what you are putting in your body. Just because something is available online doesn’t mean it’s safe. Natural doesn’t necessarily mean safe, either.

When choosing fat burners, look out for dexaprine, sibotramine (Reductix), 2,4-dinitrophenol: These compounds have been shown to have harmful effects on users, and are now controlled substances as a result.

What are the most effective fat burners?

Here’s the good stuff. A breakdown of how each fat burner works, backed up by information from government nutritionists and peer-reviewed scientific studies.

Glucomannan, a soluble fiber

The name of this supplement may be a bit of a tongue-twister, but it’s a valuable fat burner.

Glucomannan is a soluble fiber extracted from the root of a Japanese plant called konjac, or elephant yam. Soluble means it is able to dissolve in water.

The fiber promotes satiety which, as mentioned earlier, helps you to feel full after eating. This happens because the compound absorbs water and expands, triggering feelings of fullness and reducing the desire for after-dinner snacks.
Glucomannan has been found to aid with weight loss in a variety of studies (1).

Rest assured, though: Caffeine used in supplements is usually in a different form to the one that gives you an energy boost when you drink a cup of coffee. So there’s no risk of losing sleep when taking your evening dose.

Caffeine interacts with neurotransmitters like norepinephrine, which have been found to promote satiety and to maintain metabolic rates after ingestion of calories (2). This gives your body what it needs to burn the calories taken in when you eat. Preparations of caffeine extracted from green tea were found to have a positive impact on weight loss (3).

Chromium

This supplement contributes to normal macronutrient metabolism, which in layman’s terms means it affects the amount of energy we get from food.

Researchers found that chromium played a part in “reducing fat mass and increasing lean body mass” (4). It is thought that the compound increases the activity of insulin, which the body uses to metabolise and store fats, and other food-based compounds.

Chromium occurs naturally in meats and whole-grains.

Choline

The functions of this fat burner are associated with B vitamins, although it’s not yet been formally invited to join their gang.

It supports normal fat metabolism in the body, and because we are unable to produce enough to match our needs by default, supplementary choline must be included in the diet.

As we’ve said, effective metabolising of fats helps the body to use them as fuel, rather than storing them away in your tissues.

Vitamin B6 and B12

The name B6 is a catch-all term for six compounds with B6 activity, which are involved in all sorts of reactions in the body including metabolism of carbohydrates and lipids.

Vitamin B6 contributes to normal energy-yielding metabolism, and taking B6 supplements has been found to improve the ratio between fat and lean muscle in your body (5).

B12, on the other hand, contributes to essential biochemical reactions involved in the metabolism of fats.

One paper we read gives a non-layman description of the mechanism behind this reaction: “L-methylmalonyl-CoA mutase converts L-methylmalonyl-CoA to succinyl-CoA in the degradation of propionate” (6). Punchy!

Garcinia Cambogia

This supplement is as exotic as it sounds, and is extracted from a tropical fruit that grows in Indonesia. The fruit itself is often used to bring depth to curries thanks to its sharp, sour taste, but outside of cooking it is often used for its fat burning properties.

The plant has been used medicinally for many years, and its constituent chemicals have been the subject of scientific studies for at least two decades. In one study, participants taking a Garcinia Cambogia (GC) treatment had significantly reduced fat areas compared to the control group, and the results were significant to P<0.001 (7). In non-scientific terms this means the chance of this being a coincidence is lower than one in a thousand.

Two mechanisms are at play here: GC blocks an enzyme called citrate lyase, which body uses to make fat. It also stimulates feelings of fullness through interacting with neurotransmitters (8), as we introduced earlier when talking about caffeine.

Dihydrocapsiate in peppers like cayenne

This spicy-sounding supplement has a thermogenic effect (9), which means that it increases your resting metabolic rate slightly. As we saw earlier, higher metabolic rate means faster metabolism and more fat burned.

A higher metabolism also helps to stamp out after-dinner snack cravings, meaning fewer snacks eaten and fewer calories consumed.

Zinc

This fat burner is a metallic element that the body uses to aid in normal carbohydrate and nutrient metabolism. When combined with other fat burners, that’s several compounds working to have a positive impact on your metabolism.

It can be found in foods like red meat and poultry, or, if you’re partial, oysters contain the highest proportion of zinc per serving than any other food (10).

Our bodies are unable to store zinc, so supplements are a popular way of ensuring you have enough.

Chloride

This is one of two chemicals that make up table salt, known chemically as sodium chloride. Both parts help your body to break down and digest nutrients in the food you eat. Chloride in the blood stream is required to create stomach acid, which plays a huge role in proper digestion.

The right amount of chloride in your diet aids healthy digestion and reduces bloat.

We’ve dug deep for evidence supporting the use of the fat burners outlined above, with a focus on female physiology.

Research suggests that women may struggle more than men with food cravings (11), experiencing more and stronger cravings (12). This suggests that ingredients which suppress appetite (like dihydrocapsiate, glucomannan and others) may be particularly helpful fat burners for women.

By focussing on appetite, the need for stimulant supplements is reduced. Natural vitamins and essential minerals also help to eradicate deficiencies and promote your bodies natural ability to burn calories without side effects, and are a great option for women looking to lose weight as a result.

When to take fat burners?

Take fat burners alongside a healthy diet and regular exercise, and they will provide an extra boost to your weight loss efforts.

As we said earlier, there is no magic pill, and anyone telling you there is should not be believed. A combination of fat burning compounds can work together to improve the effectiveness of your metabolism, and your wider weight loss efforts.
Supplements should be taken as directed for optimum impact. By taking doses evenly throughout the day, you give your body the chance to get the most from each capsule. Taking more than the recommended amount will not have additional effects, and is not a way to lose more weight more quickly.

Fat burner side effects

Some of the supplements outlined above come with the possibility of side effects.

You may feel thirsty, because glucomannan absorbs fluid in your stomach. Having an extra glass of water should be enough to counteract this.

Caffeine can potentially hinder the effects of the contraceptive pill, so make sure you speak to your GP if this is relevant to you.

Constipation was reported in some scientific studies exploring the effects of caffeine, but it is worth noting that this was at a very high dosage.

A quick overview of five of the most popular fat burning supplements available on the market.

They are Lean Bean, Powher, GNC Lean Shake, BodyDynamix™ Slimvance® Core Slimming Complex Stimulant Free, and Lean Pm Night Time Fat Burner.

Read on, and find out everything you need to know.

1. Leanbean

What’s in it?

• Glucomannan, taken from the konjac plant.
• Cromium picolinate to support normal macronutrient metabolism.
• Vitamins B6 and B12 to support normal energy-yielding metabolism.
• Green tea, with caffeine to gently energise you.
• Green coffee beans: Another source of caffeine, extracted before the beans are roasted.
• Acai berry: Naturally high in fiber, fatty acids, and electrolytes.
• Raspberry ketones, which have similar properties to cayenne.

Key features:

The number 1 choice of female athletes, thanks to its cutting-edge list of natural ingredients.

Designed to support a normal energy yielding metabolism but with less stimulant than men’s workout supplements.

A serving suggestion:

Taking Lean Bean is simple: Just take one capsule four times each day, with a meal or a snack.

2. Powher

What’s in it?

• Natural caffeine, to give you a pre-workout energy boost.
• Coconut water powder, rich in electrolytes to help you maintain balance.
• Vitamins B5, B6, and B12 to support metabolism and reduction of fatigue.
• Oxyjun, a caffeine amplifier that boosts the benefits while reducing the side effects.
• Enxtra, which is a combination of three extracts: C.Flexuous oil (LG), and water soluble extracts of A. galanga and G. glabra. Another caffeine booster.
• Rednite: A type of beetroot rich in nitrate and antioxidants.

Key features:

A tasty pre-workout drink designed to improve motivation and endurance, without adverse side effects or the dreaded caffeine crash.

Free of muscle-building ingredients – like creatine – which can leave you looking bulky.

A serving suggestion:

Mix a 10g scoop into water to create a balanced pre-workout drink.

We worked tirelessly to create a unique, refreshing flavour – Pink Lemonade – that makes Powher stand out from the crowd.

3. GNC Lean Shake

What’s in it?

• Protein blends, to refuel your muscles after exercise, contribute to positive body balance, and help you to feel full.
• Whey protein concentrate to build strength and muscle, and help with weight loss.
• Safflower oil, which is a good source of CLA.
• Sunflower seed oil, a good source of omegas.
• Various vitamins and minerals, including Vitamin B6, B12, calcium, zinc, chromium, potassium, copper, and selenium. These contribute to healthy bones, blood sugar levels, immune system function, and other vital body needs.

Key features:

Each serving contains 25g of protein and 8g of fiber.
Made with 23 vitamins and minerals.

A serving suggestion:

There are a range of tasty flavours, just mix one heaped scoop with water, and drink!

Choose from Rich Chocolate, French Vanilla, Mixed Berry, Cookies and Cream, Banana, Orange Cream, Snickerdoodle (non-US readers: It’s a type of cinnamon biscuit), and Chocolate Peanut Butter.

4. BodyDynamix™ Slimvance® Core Slimming Complex Stimulant Free

What’s in it?

• Moringa oleifera leaf extract, which is a good source of vitamins and minerals.
• Murraya koenigii leaf extract: High in fiber and included to support gastrointestinal function.
• Caffeine ahydrous: A dehydrated form of caffeine.
• Capsimax fruit extract delivers thermogenic benefits.
• Piperine: Another familiar name, which has been studied for potential benefits of absorption.

Key features:

A select blend of natural ingredients to help assist during your weight loss journey: Claims to help you achieve 6x more than you would from diet and exercise alone.

A serving suggestion:

Simple: Just take two capsules per day, one thirty minutes before breakfast and one before dinner.

5. Lean Pm Night Time Fat Burner

What’s in it?

• Green tea extract: The gently energising source of caffeine.
• Melatonin, which improves sleep and metabolism at the same time!
• Vitamin B6, which supports natural energy-yielding metabolism.
• Magnesium to help reduce tiredness and fatigue.

Key features:

Claims to promote deeper, more restful sleep, so you wake up feeling energized.

Increases metabolism to help your body burn fat while you sleep.

A serving suggestion:

Take two capsules each night before bed, ideally on an empty stomach.

Conclusion

Fat burners come in various guises, and work through various mechanisms. The key mechanisms are increasing metabolic rate, increasing your temperature, suppressing appetite, reducing nutrient uptake, and increasing your energy. Effective supplements will often target more than one, if not all of these mechanisms.

When it comes to losing weight, evidence suggests that natural ingredients like glucomannan and caffeine are best, and they should help you to achieve greater weight loss than you could on your own.

Minerals and vitamins like B6, B12, choline, chromium, and chloride will support your body’s natural ability to burn fat and stay in shape.

When taken in conjunction with lean meat, more proteins, slow release carbohydrates, healthy fats, and while getting good sleep and staying properly hydrated, fat burning supplements can provide a huge boost to the results of your weight loss.