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fat burning pills

A guide to the best fat burners

23 Nov 2022 • 3 min read


When most people aim to lose weight, more times than not, it’s fat they want to lose. Our bodies will naturally burn excess fat to fuel our bodies when we achieve a ‘calorie deficit’, through exercise or diet, which causes our body to tap into excess fat to ‘run’ our bodies.

Fat burners are nutritional supplements that claim to help our bodies to burn more fat. They are usually made by combining naturally occurring ingredients like caffeine, green tea, l-carnitine and chromium – to name a few. Each ingredient is said to have individual benefits to our fat metabolism, and can be seen as an easy, convenient way to support weight loss.

However, fat loss can be a real challenge, causing some people to develop unhealthy habits. So, with fat burners, you need to make sure what you’re putting into your body is safe and allows you to burn fat in a healthy way.

In this guide, we want to help de-mystify the science behind some of the most popular fat burners ingredients and highlight some of our best-selling fat burners to help you decide if using one is right for you.

Do fat burners work?

The claim made by many producers of fat burning supplements is that their product can make you feel more energised as well as stimulate your natural metabolism and encourage it to burn more calories. After all, it is excess calories that cause our bodies to store any energy we haven’t used into bodily fat – ready to use when we need it.

Don’t be duped into believing you can just pop a pill and watch the fat melt off, though. Most fat burners have been designed to be used in conjunction with a healthy diet and exercise and to enhance this weight loss routine, not replace it.

Be careful: stay wary of companies that claim their fat burners can offer you some sort of ‘miracle’ solution to your weight issues. Fat burners can’t control what our body does with energy, but some of them can potentially give us a little boost in our fat loss.

Get your diet and exercise routine down before thinking about fat burners

Here is some general advice on losing weight safely and healthily, but please always consult your doctor before taking on any specific weight loss plan. Especially if you have existing medical conditions or seek specific weight-loss advice.

Calories in vs calories out

Fat burners are only going to work if you make sure your body is burning up more calories than you’re putting back into it. That’s how you lose weight. Whether you invest in a smart watch, calculate your TDEE (total daily energy expenditure) with an online calculator or use a service like My Fitness Pal to determine roughly how many calories your body burns in a day, this is a good place to start.

Once you know how many calories your body needs to support you through your daily life and maintain your weight, you can start eating less than that to lose weight. Exercising increases the number of calories your body needs, so you have more to play with. E.g. if you figured out you need 2000 kcal a day to maintain your weight you could aim for 1700kcal with no extra exercise or burn 300kcal by running, swimming, etc and not cut your calories at all.

Take it slow

It’s best to take the slow and steady approach to weight loss, as you want it to be sustainable and not just a rapid loss followed by a rapid re-gain once you go back to normal. It’s all about healthy habits. Once you get to your desired weight, you can eat more to maintain your weight.

You also need to make sure you’re eating plenty of fruits, veggies to fuel your body with all the vitamins and minerals it needs. As well as ensuring you’re consuming enough protein, healthy fats and complex carbs to fuel you through your daily life and exercise routines.

Did you know fat needs to be oxidised? The phrase ‘burning fat’ is more of a catchy phrase and shouldn’t be taken literally, as fat is actually oxidised. Meaning your body needs oxygen to get rid of fat. This is why slow and steady cardio is essential to decrease your bodies fat content.

When you gain muscle, you burn more calories

Remember that gaining muscle can increase your metabolism, literally just sitting on your sofa with more muscle will burn more calories than if you hadn’t gained muscle. This makes strength training a good idea if you want to burn fat.

Don’t be ruled by the scale

Weighing yourself may be an easy way to track your weight loss, but it shouldn’t be everything. As mentioned above, muscle weighs more than fat yet it takes up more room. So, if you have been strength training alongside a calorie deficit, you may not actually weigh any less, even though your jeans may fit better.

Consider taking measurements of your chest, waist, hips and thighs (or anywhere really) with a tape measure so you can see if you’re losing inches, even if the scale doesn’t seem to be budging.

Only when you are happy you are on track to losing fat in a healthy and sustainable way should you consider fat burners.

Think of them of the icing on the cake; a supplement to take all the good work you’re doing and supercharge it a little.

Are there natural fat burners?

Yes! Most ingredients in fat burning products are actually completely natural and we could already be consuming fat burning foods and ingredients in our diets. Let us take you through the most popular natural fat burners and how they work.


Caffeine, it’s in our tea, our coffee and there’s even a little in our chocolate bars! When you think about how we use it in our day-to-day lives, it’s not so surprising that it’s a popular fat burning ingredient. Think about it. When we get up in the morning, a lot of us straight-up refuse to talk to anybody else until we have our morning coffee! It gives us that buzz we need to get up and go seize the day, all while ramping up our metabolism.

A study on caffeine and its effects on the metabolic rates of people with a normal weight and obese people was conducted in 1980 by The American Journal of Clinical Nutrition and this is what they found:

Normal weight participants were given coffee with a caffeine content of 8mg per kg of the person’s body weight and their metabolic rate ‘increased significantly’ during the 3 hours after caffeine ingestion, and fat oxidisation (fat burning) also increased significantly in the last hour, compared to a control group who received a placebo.

Obese subjects and a control group with a normal weight were given coffee with a caffeine content of 4mg per kg of the person’s body weight caffeine content and both groups experienced an increase in metabolic rate, however only the control group had an increase in fat oxidation.

According to this study, coffee increased the metabolic rate of both normal-weight and obese individuals, accompanied by greater fat burning in normal weight subjects.1

Considering that the average mug of instant coffee has 100mg of caffeine and a mug of green / black tea comes in around 75mg caffeine, the dosages of the study were quite high, e.g. a ‘normal weight’ 70kg man would have been given 560mg of caffeine in the first experiment. That equates to almost 6 mugs of coffee! The second experiment would have been around 3 mugs for the same man.

However, if you don’t like the taste of tea and coffee or can only really stomach one cuppa in the morning, caffeine extract could be a better choice. A lot of fat burners include caffeine extract in their arsenal against fat, e.g. Grenade Thermo Detonator Capsules contains 250mg of green tea extract, 112.5mg of caffeine extract and 5mg of green coffee extract in each tablet, alongside other natural ingredients.

Be careful: if you are naturally sensitive to caffeine (one cup of coffee and you’re buzzing), be careful with fat burners containing caffeine as one of their active ingredients. You may have to surrender your morning coffee or go for a fat burner with less caffeine.

Green tea extract

Similar to pure caffeine, green tea extract can help you feel alert, energised and give your metabolism a boost. It does contain caffeine, but another of its ingredients called catechin is where it’s real fat burning properties lie.

Studies have shown that catechins can work alongside caffeine to increase your body’s metabolism and encourage it to burn more fat.2 Green tea is a popular ingredient in fat burner supplements, like Nutritional Headquarters Fat Metaboliser Tablets which contains 250mg of green tea extract, amongst other ingredients.


L-Carnitine is made by our bodies to help it transport body fat to use for fuel. This makes it essential for fat loss as that’s how we get rid of excess fat – taking it and using it for the general running of our bodies and using it up during exercise.

So why would it be used in fat burners? Well, studies suggest that when L-Carnitine is taken as a supplement it can significantly improve weight loss, even if this initial weight loss will decrease over time.3 L-Carnitine has also been seen to enhance muscle metabolism and athletic performance, when used long term.4 Short term weight loss, long term muscle and performance improvements – nice!

Bitter Orange

Bitter orange has been used as a traditional Chinese medicine for centuries to help ease the symptoms of nausea, indigestion and constipation. It’s still popular now, and you’ll often find it amongst other ingredients in fat burning products.

The active ingredient in bitter orange is p-synephrine, which is structurally similar to the stimulant ephedrine. Some studies have found that taking bitter orange in combination with other ingredients can result in significant increases in resting metabolic rate (the way our bodies use energy when we are simply sitting / laying down / relaxing)5. This means that we use up more energy and could mean that our bodies turn to excess fat to do so – obviously diet and exercise play a big part in this, but it could provide a bit of extra help!


Guarana is a plant native to the Amazon basin in Brazil and has been used by Amazon tribes for centuries. Now, everybody else wants in on the action! Guarana extract is made by processing the fruit seeds into a powder. This powder is full of stimulating ingredients like caffeine, theobromine and theophylline, as well as powerful antioxidants like catechins and tannins. Some studies have found that guarana can increase energy expenditure and help prevent fatty tissue accumulation.6


CLA (conjugated linoleic acid) is an omega-3 fatty acid that you can find naturally in dairy and meat, especially if the animals are grass fed as the LA (linolenic acid) part comes from grass and grains. CLA supplements are usually made from LA found in sunflower oil or safflower oil, which is then altered using live bacteria, enzymes or chemicals to transform it into CLA.

What’s so good about it? CLA is thought to trigger chemical reactions to help your body burn fat. It has been seen to improve metabolism, insulin resistance, the way our bodies mobilise stored fat and can also help to kill white fat cells.

Some studies have shown that CLA can help people lose fat, even with no change to diet or lifestyle!7 However, combining CLA with a healthy lifestyle can produce even better results. A Norwegian study compared 2 groups of healthy adults who exercised three times a week for 90 minutes, for 12 weeks. The group who took CLA lost more body fat than those who were just exercising.8

Tried and tested: the best fat burning pills and supplements

So now you have some information about the most popular fat burning ingredients and why they are used in fat burners, we are ready to give you the low down on some of the most popular fat burner supplements themselves. This should help you decide which fat burner is best for you and your needs, if you decide to try one out.

Grenade Thermo Detonator Capsules

Grenade’s flagship product, the Thermo Detonator Capsulesclaim to deliver boosted sports performance as well as fat loss. These fat burning pills contain green coffee, phenylalanine, cayenne, bitter orange powder and green tea, to maintain your energy levels and well as help burn more fat, alongside a sensible diet and exercise programme. But do they really work? Let’s see what some of our customers thought about them (reviews from our website):

Brilliant product *****

‘I've been using these for 1 week and they've made training so much easier. I've went from running 2 miles (12 minute miles) 3 times a week to 4 miles (10 minute miles) 3 times a week. I definitely recommend to anyone who struggles to find the energy to workout.’ – Tallen

Spikes Energy Levels *****

‘I have been using Grenade for about 2 years and cannot do without it. It's a excellent energy booster for the gym and gives you that little edge when you feel like giving up. I haven't received any side effects from taking it but that might only be because I only take one capsule a day before a workout, instead of the recommended 2 capsules.’ –  Sexy Mumma of Five

Medi-Evil Excalibur Metabolic Magic Capsules

Another great fat burner for you gym fanatics out there, these Medi-Evil capsules contain green tea which can help burn fat alongside a healthy diet and exercise plan, as well as l-carnitine, caffeine and bitter orange. See what our customers have to say about them:

These are awesome, used correctly. *****

‘These are fantastic, work brilliantly if you follow the instructions properly and concisely. Highly recommend.’ – JonnyO21

Amazing Burner *****

I was swayed away from my usual brand by a friend recently and decided to purchase in store. Although it has slightly fewer caps than my usual there are actually far more days use and the product is way more powerful. Will definitely buy again. Thanks.’ – PercyB

Nutritional Headquarters Fat Metaboliser Tablets

These fat metaboliser tablets have been designed to help you reach your weight management goals, while letting you know that they’re here to support not do all the hard work for you! Each capsule contains green tea extract to help your body burn fat. Do these fat burning pills actually work, though? Let’s see what customers from our website had to say:

They definitely make a difference ****

‘I’ve taken these on and off for several years, I only stop taking them if I forget to buy them. I must say that there’s definitely something about them that helps me lose weight faster, I can tell the difference if I haven’t taken them. They’re not overnight miracles, but taken with a sensible diet and any normal 9-5 active day, they definitely make a difference in the long run. I’m not very overweight, I used to be, but I’ve never been to a gym or exercised, and I take these every day before work, they give me a slight buzz of energy and positive attitude.’ - Martyn123

Weight loss *****

‘I feel as though these really helped speed up my weight loss goal, along with counting calories and exercise.’- Happy0987

Please remember fat burners are only an aid – they can’t do the work for you. A healthy diet and regular exercise are key to keeping you healthy. Never put your health in danger to lose weight, and remember – all bodies are beautiful!

Last updated: 8 September 2020


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