Best Fat Burners to Buy in UK in 2021

This page may contain affiliate links and we may earn a small amount of money from any products bought. Our reviews, however, remain independent and impartial.

Fat Burners aren’t miracle pills; they won’t melt away the pounds or kilos if you don’t put the work in. BUT they can be an extremely powerful aid in your diet and exercise regime, and one that could mean the difference between reaching your target weight or falling short.

An effective fat burner will work on several different levels:

1.            Suppressing appetite – helping you to avoid snacking

2.            Boosting the metabolism, encouraging thermogenesis, enabling the body to burn more calories

3.            Protecting lean muscle mass, ensuring your muscle isn’t used as fuel (a common issue when dieting)

 

Why Do You Need a Fat Burner?

You don’t need a fat burner, but why wouldn’t you try one? Especially if it makes sticking to your diet and exercise regime that bit easier and leads to improved weight loss at the end of the day. Missing out on a fat burner could mean you lose more muscle but less fat and struggle with your workouts along the way.

Ideal Ingredients in a Fat Burner

There are a few proven ingredients that we like to see in a fat burner. They include:

HMB – a leucine-metabolite (that is at least 20 times more potent than leucine itself) that helps to preserve muscles. Fasting and weight loss tends to also cause muscle loss which is what you don’t want as it impedes your workout performance and lowers your resting metabolic rate (the number of calories your body burns while at rest). HMB can prevent this.

Capsaicin – a thermogenic compound extracted from cayenne chilli peppers that raises the body temperature to burn more calories. 

EGCG – a green tea extract that contains a potent amount of catechins. These are very useful for weight loss because they encourage the body to breakdown fat as opposed to using muscle proteins.

Piperine – fantastic bonus compound that encourages digestive uptake, making all the other ingredients work better. 

Optional – Caffeine: A classic fat-burning compound due to its anti-fatigue and calorie-burning properties. Make sure you keep below the 400mg a day recommendation. You don’t necessarily need caffeine in your fat burner, however; indeed many inferior products cram products with caffeine to hide the fact that they don’t offer much else.

There are several superior non-stimulant fat burners on the market, including our favourite Burn Lab Pro…

Burn Lab Pro: Best Stimulant-Free Fat Burner

* From the manufacturers of the popular Mind Lab Pro and the Performance Lab range 

Boasts: Impressive ingredients, clinically effective dosages AND no stimulants.

Ideal For: Fasted training, thanks to its ability to promote lean muscle mass, but also suitable for anyone following an exercise regime. Pledges to burn more calories and fat than exercise alone.

We are huge fans of Burn Lab Pro. Its ingredients work well in synergy to trigger thermogenesis, boost exercise and gym performance, and help you retain your lean muscle mass. It’s an effective choice for anyone wanting a stimulant-free all-natural fat burner.

Athletic Endorsement

Don’t just take our word for it… Burn Lab Pro is a favourite with athletes too. Aljamain ‘Funk Master’ Sterling, the #1 Ranked Bantamweight MMA Fighter, has officially endorsed Burn Lab Pro. He explains why here, explaining that it helps him to lose fat, and not muscle, ahead of a fight. 

The Formula

HMB, 1.500mg: A ‘child’ of the BCAA leucine, HMB is an effective ingredient for preserving muscle mass. This is particularly important when fasting while training as muscle is often degraded during this time. HMB is considered much more powerful – 20 times as much – than its parent leucine.

Coleus Forskohlii, 375mg: Used in Ayurvedic medicine, the herb Coleus Forskohlii contains the active ingredient Forskolin, a strong research-backed ingredient shown to burn fat and build muscle in clinical trials. Also optimises the metabolism. 

Capsimax®, 75mg: This cayenne pepper extract encourages the production of hormones to raise the metabolism and body temperature, helping to burn fat. Crucially, it does so without any negative effects on heart rate or blood pressure.

BioPerine, 3.75mg: This black pepper extract is known to promote the absorption of other ingredients in the formula, rendering them more effective.

NutriGenesis GTF Chromium: GTF Chromium has been shown in studies to be linked to a significant reduction in bodyweight. It may help you to lose weight by enhancing insulin action helping with fat storage; keeping body sugar within normal range and regulating appetite, and by supporting the metabolism to deal efficiently with fats, proteins and dietary sugars.

OUR CONCLUSION: Burn Lab Pro is an excellent choice for anyone looking for a safe, stimulant-free fat burner that specialises in fasted training. It’s refreshing to see a fat burner that eschews numerous ingredients and instead concentrates on a few that WORK.

BUY!

BUY: Only available direct from the Burn Lab Pro website

Read our Full Review of Burn Lab Pro

Instant Knockout Cut: Best to Melt Fat (Ultimate Shredding)

NEW MARCH 2021 FORMULA!

** Formerly known as Instant Knockout.

Boasts: Extensive research, natural and proven fat burning ingredients

Ideal For: For when you need to melt the fat and are prepared to put in the work.

Instant Knockout Cut (Instant Knockout 2.0) is an updated 2021 formula that can deliver a winning punch to anyone seriously following an intensive diet and exercise regime. Its mix of green tea, caffeine and cayenne powder should boost your metabolism enough to help burn fat even while you catch some Zzzs. This is backed up with glucomannan, a dietary fibre that helps to suppress the appetite.

The 2021 formula of Instant Knockout Cut adds L-theanine, included to offset any negative effects of the 300mg of caffeine included in Instant Knockout Cut. L-theanine is an anti-anxiety nootropic known to enhance the useful benefits of caffeine — more energy, focus and intensity — while dialling down its potential negatives. Meaning you can enjoy the upside and not have to worry about jitters, anxiety or a subsequent energy crash as the caffeine wears off. 

The Instant Knockout Cut Formula

Instant Knockout Cut’s core ingredients include green tea extract (a recognised fat burner that sparks thermogenesis and has been shown to reduce body fat — as well as cayenne pepper (raises body temperature, suppresses hunger), caffeine anhydrous, and glucomannan (a dietary fibre which swells after eating to help you feel full, effectively suppressing the appetite.)

These are combined with vitamin B6 and B12, vitamin D,  L-theanine, and black pepper extract. All of which help to boost protein synthesis, elevate metabolism and aid energy, among other benefits.

Together they help to ‘activate a whole body burn’, increase energy levels, boost your metabolism, and aid weight loss. We’re talking full-on thermogenesis along with appetite suppression and enough energy to make your workouts really count. Backed up with some important vitamins and amino acids.

OUR CONCLUSION: If you are serious about losing fat and retaining muscle, you need to opt for a serious fat burner too – and Instant Knockout Cut is as serious as it gets. Delivers a strong, natural fat burning punch.

BUY!

BUY: Direct from Instant Knockout

Hourglass: The ‘Intelligent Fat Burner for Women’

Boasts: Solid fat burning ingredients with an honest, female-friendly realistic approach to weight loss. Has a strong focus on tackling snacking.

Ideal For: Women who want an approachable fat burning solution, exclusively aimed at, and designed for, women.

Many fat burners on the market say they are appropriate for women as well as men, but their literature speaks volumes: lots of pumped-up muscled men, and names that conjure up ultra-macho activities. Hourglass is a refreshing change – a fat burner aimed at women, with subtle packaging and female-friendly marketing.

Its promotion is full of positive body-confident messages, such as choosing its name because an ‘hourglass shape looks great, no matter what size you are’.

The Formula

Hourglass uses nine ingredients to help you burn fat via slightly different pathways. They include popular dietary fibre, glucomannan (1500mg), which absorbs water to swell in the stomach, promote satiety and slow down the emptying of the stomach. It is an effective appetite suppressant.

Added to that is green tea extract (500mg), one of the most effective fat burning ingredients around, raising levels of the hormone norepinephrine. Guarana, 100mg, provides an energy and metabolism boost, thanks to its natural caffeine. It is a stimulant, so you won’t want to take Hourglass at night.

Other ingredients include Capsimax (100mg), a hot pepper extract to boost thermogenesis; vitamin B6 (as P-5-P) to boost carb burning; vitamins B12 (to balance female hormones) and D3, chromium (helps to prevent cravings by normalizing sugar levels in the blood) and BioPerine to boost the formula’s effectiveness by boosting absorption.

OUR CONCLUSION: Don’t be fooled by the friendly yellow packaging; this fat burner for women is just as effective as any of the traditional macho-styled fat burners on the market. Many of the same ingredients are found in Instant Knockout, for instance.

We like the fact that Hourglass focuses on tackling snacking – a key female-focused diet issue – with its glucomannan, cayenne pepper and chromium mix. Snacking is often the downfall of many weight loss endeavours, and research shows women tend to eat an average of 450 calories a day from snacking alone.

BUY!

BUY: From the official Hourglass website

Read our Full Review on Hourglass

Hunter Burn – Premium Fat Burner for Over 40s Men

Hunter Burn is one of the three products in the Hunter range from popular UK supplement company, Roar Ambition, coincidentally the makers of Instant Knockout. The other products are Hunter Test (T-booster) and Hunter Focus (nootropic), making it clear that the Hunter range is aimed at men, though there’s nothing in Hunter Burn that wouldn’t suit women too. The Hunter range also seems to be aimed at a slightly older audience as well, possibly the over 40s.

Hunter Burn’s formula is impressive. It combines traditional fat burning ingredients such as glucomannan, the dietary fibre that expands in the gut to promote satiety and reduce appetite, alongside green tea and cayenne pepper. But it combines them with promising new substances such as white kidney bean extract — a carb blocker — and vitamin D3 (not a new ingredient per se, but unusual for a fat burner yet shows promise), 

We’re particularly excited by its decision to include Matcha Green Tea as opposed to normal green tea. These are green tea leaves ground into powder and consumed as a drink. As a consequence of not having to throw the leaves away (as you do with normal green tea), Matcha Green Tea is higher in nutrients, caffeine and fat-burning antioxidant, EGCG. We’re also impressed by the 200mg of nootropic Theanine that it chooses to add, ensuring the higher caffeine content in the green tea won’t leave you with the jitters.

All in all, Hunter Burn deserves a mention on our Best Fat Burners in the UK list. This is a mature fat burner for mature people.

BUY!

BUY: Direct from Hunterevolve.com

Read our Full Review of Hunter Burn

Performance Lab Omega-3: For Creative Fat-Burning 

Performance Lab Omega-3 is a slightly unusual addition to a fat burner page but it’s a creative weight loss solution that perfectly complements a top-notch fat burner. Performance Lab Omega-3 can be an ideal boost to a weight loss and exercise regime because it:

• May help to reduce hunger and appetite.

In one study, people taking 1.3g of Omega-3 oil reported feeling significantly fuller for two hours after food than those taking a lower amount. The researchers concluded that a diet rich in Omega-3 fatty acids could help modulate satiety in obese or overweight individuals when on a calorie-controlled diet.

• May increase metabolism to help burn more calories.

Several studies have demonstrated that adults taking Omega-3 saw their metabolic rates increase by up to 14% — the higher your rate, the more calories you burn, making it easier to lose weight and to maintain it. Most of the studies also reported a boost in muscle mass, which burns more calories than fat, and may explain the improved metabolic rate.

• Research suggests Omega-3 may boost the amount of fat and calories you burn during exercise

Some studies have discovered that taking Omega-3 supplements alongside an exercise regime encourages more weight loss and reduced body fat than exercise alone. Researchers suggest this may be because consuming long-chain n-3 fatty acids may encourage the body to use fat as fuel during exercise rather than carbs. One study demonstrated that women burned 10% more calories and burned up to 27% more fat while exercising when taking Omega-3.

• May help you to lose inches and body fat

Studies into the benefits of Omega-3 have shown that it may help people to build muscle and lose body fat, even if it doesn’t change their weight on the scales. As we all know, muscle weighs more than fat, so it makes sense that you can lose fat and inches and yet supposedly not see any change in your weight.

Several studies, for instance, have demonstrated that people lost more body fat and gained more muscle than those who didn’t take Omega-3 supplements, even though their overall weight didn’t change. An analysis of 21 studies concluded that Omega-3 helps to reduce waist circumference, as well as waist-to-hip ratio.

For all these reasons, we recommend taking an Omega-3 supplement as part of your fat-burning regime. It can be taken in combination with any of the fat burners mentioned above on this page.

About Performance Lab Omega-3

Here’s why we believe Performance Lab Omega-3 is the best Omega-3 available to buy on the UK market today. Most Omega-3 supplements are sourced from fish and fish oil – which often comes with a fishy taste or smell. Plus, if the fish come from polluted waters, you are unknowingly ingesting toxins and harmful chemicals.

In contrast, Performance Lab gets its Omega-3 right from the source – the algae the fish eat. It’s the algae that contain the Omega-3 found in fish, and by-passing the (fishy) middleman, it removes the fishy taste, smell, impact on fish stocks, and potential toxins altogether! It’s also suitable for vegetarians and vegans. It’s ingenious, really.

Performance Lab Omega-3 is also one of the cleanest supplements of its kind – it’s free from GMO, allergens, soy, gluten, and synthetic additives; is non-irradiated, and is ethically-sourced with little carbon footprint. It also uses plant-based capsules containing probiotics for easier digestion.

With this product, Performance Lab seems to have thought of everything, and we are happy to recommend Performance Lab Omega-3 as our favourite Omega-3 supplement to buy in the UK today. We also recommend it for adding an extra oomph to your fat burning, weight loss, and inch loss activities.

BUY!

Buy Performance Lab Omega-3 

Omega-3 is also one of the most beneficial nutrients you can find — find out how else you can benefit from Omega-3 here

SPECIAL MENTION: Grenade Thermo Detonator: Amazon UK’s Most Popular Fat Burner

We want to make a special mention of the phenomenally popular Grenade Thermo Detonator, mostly because, well, how can we not?! It has been Amazon UK’s No 1 Best Selling Fat Burner on and off for a long time now.

But it needs to come with a warning.

Anyone taking Grenade Thermo Detonator can’t help but notice the massive kick it gives you – that’s thanks to its high caffeine content (500mg green tea, 225mg caffeine, 10mg green coffee per two capsules; a daily serving is double that). Added to that is the controversial ingredient Bitter Orange (420mg per two caps). The active ingredient in Bitter Orange is synephrine, a less potent fat burner than ephedra which was banned for its potential heart-related issues. While it may be less potent, there is still concern than synephrine also stimulates the heart, however.

Indeed, WebMD lists Bitter Orange as ‘POSSIBLY UNSAFE when taken as a supplement for a medical purpose such as weight loss.’ It goes on to add that either when taken by itself or used in conjunction with caffeine, bitter orange could ‘increase the risk for high blood pressure, fainting, heart attack, stroke, and other severe side effects’

OUR CONCLUSION: Grenade Thermo Detonator is so popular that we can’t ignore it, but we personally stop short of endorsing it. Its high caffeine content and Bitter Orange may make the product effective, but we’re not thrilled with the potential safety issues.

Use at your own discretion.