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What is a Fat Burner?
The term ‘fat burner’ doesn’t really do justice to most of the products that fit in to the category. They generally do a lot more than simply burn fat – some provide energy and double as a pre-workout, others suppress your appetite to help support weight loss.
Fat burner is a catch-all term that is mostly interchangeable with other terms you might see like ‘thermogenic’, ‘weight management’ or ‘diet pill’. They are all geared towards helping you shed fat while maintaining muscle mass and energy levels. Different labels, but a similar result.
That end result doesn’t just come from the product though. You won’t get anywhere popping these pills and sitting around all day waiting to get skinny. There’s not a pill in the world that will do that.
Fat burners grease the wheels of weight loss, but it’s up to you to hop up on to that bike and start pedalling if you want to get anywhere!
After reviewing dozens of supplements, we believe that Performance Lab SPORT Burn is the best stimulant-free fat burner currently available on the market.
Or read on to learn why we chose this fat burner as our #1 stim-free option.
Why Choose a Stim-Free Fat Burner?
If you’re someone who avoids stimulating ingredients altogether then that’s an obvious reason to choose a stim-free fat burner – but not the only reason.
Despite the common consensus about the morning being the best time to exercise, most people get around to it in the afternoon or evening. This is not the best time of day to be taking stimulants, as they could affect your appetite and almost certainly will affect your sleep.
Most stimulants come with potentially adverse side-effects too. Caffeine is an obvious example and can induce jitters, anxiety, nausea and insomnia among other things.
Whether you want to avoid stimulants out of convenience, health or principle, you’re in the right place, because we’re going to let you know the three best ones around in 2020.
Key Ingredients to Look for When Choosing a Stim-Free Fat Burner
As is the case with everything in the supplement world, there are things that have been proven to work, things that probably work but we don’t know how, and things that definitely don’t work.
The following ingredients are the MOST EFFECTIVE non-stimulant fat burners around that are backed up by scientific evidence.
Beta-Hydroxy Beta-Methylbutyrate (HMB)
Legend has it that no one actually knows how to pronounce the full name of this compound correctly, so it’s simply known as HMB.
It’s produced in your body when the amino acid leucine is broken down and is responsible for reducing muscle breakdown – something you want to avoid if you are trying to lose weight and maintain muscle mass.
There is a mountain of research supporting the effectiveness of HMB and it’s a perfect supplement if you’re trying to get lean.
Or, more specifically, the active ingredient forskolin. This nifty little plant was a secret of the doctors of Ayurvedic medicine for hundreds of years before the rest of the world caught on.
It helps to release stored fat from your cells to be metabolised for energy. It’s not amazingly effective on its own, but as part of a well-constructed formula, it can really accelerate weight loss.
Cayenne Pepper Extract
The active ingredient in peppers is capsaicin – a thermogenic chemical that can help you burn more calories and depress food cravings.
It’s possible that you can build up tolerance to these effects over a long enough time frame, but that doesn’t mean it’s not an essential ingredient in any fat burner, stim-free or not.
Top 3 Stim-Free Fat Burners
The UK market is not exactly drowning in quality stim-free fat burners at the moment, and that’s a shame. But thank goodness we have the small handful of options we do because each of them is extremely effective (and we’re going to stress this again here) under the right circumstances.
OUR FAVOURITE: Performance Lab SPORT Burn
* Formerly known as Performance Lab Sport Fat Burner
Performance Lab has had an incredible few years, releasing a slew of quality products to rave reviews. One among their roster is SPORT Burn.
Performance Lab have two product ranges – CORE and SPORT. The CORE products include multivitamins, a prebiotic, a nootropic and support for your brain, eyes and sleep.
The SPORT range is specifically targeted to support different aspects of sports performance and nutrition. Stim-free is kind of their thing as they opt instead to create formulas that optimise your body’s natural rhythm and processes.
SPORT Burn is the only one on our list to base its formula around HMB – the most scientifically sound stim-free fat burning ingredient. It also contains extremely high-quality sources of forskolin and capsaicin, as well as Bioperine to turbo charge the already excellent formula. Additional calcium and highly bio-available GTF Chromium round out the formula.
Where the other two fat burners on this list get it about 70-80% right, Performance Lab are about as close to 100% as it’s possible to be. You could argue that some green tea extract wouldn’t do any harm, but then you would not get much, if any, extra benefit from it and it’s not worth sacrificing space in the formula.
One thing Performance Lab do very well is make their products complement one another, allowing their customers to create stacks to suit any training goal.
Want to burn fat and build muscle? Burn + Protein.
Looking for the ultimate pre-workout stack? Burn + Pre (also stim-free).
Interested in just melting as much fat away as possible? Burn + MCT.
Maybe all-day energy and fat burning is your bag? Burn + Energy.
Seriously, the number of combinations is almost endless, and if you want to add a third product to your stack you can really get creative and experience some mind-blowing results. Not that the results of taking one supplement like Burn in isolation aren’t impressive enough of course!
Burn is head and shoulders above the rest when it comes to stim-free fat burners and that’s not likely to change any time soon.
Bulk Powders Complete Thermogenic Stimulant Free
Bulk Powders is another British institution that keeps churning out quality products at more affordable prices than their closest competitors.
For their stim-free thermogenic they have opted for a formula containing L-Carnitine and caffeine-free green tea like Thermo Detonator® (next on our list). To this, Bulk Powders have added B vitamins, Tetradecylhiocetic Acid (TTA) and Bioperine – a patented pepper extract that improves bioavailability and absorption of everything else in the formula.
B vitamins are helpful but not essential for losing weight. Their role is to support healthy metabolism but there is little evidence that they can increase it to help you lose more weight.
TTA is an interesting ingredient that has proven very beneficial for losing weight in animal studies. It increases fat metabolism while maintaining muscle mass and was found to help a group of rats on a richer diet lose more weight than the less well-fed placebo group.
But as for studies on humans? Less encouraging unfortunately. On its own, TTA can reduce LDL (the ‘bad’ cholesterol) and triglyceride levels but doesn’t directly impact weight loss. It might be that as part of a formula like this that contains thermogenic ingredients it becomes a little more useful by helping your body metabolise fat at a higher rate.
Grenade® Thermo Detonator® Stim Free
We have a lot of respect for Grenade® here at Supplement Reviews UK. Having turned 10 last year, the company has gone from strength to strength and continues to offer quality products backed up by one of the strongest brands in sports nutrition.
Thermo Detonator® Stim-Free might seem like a watered-down version of the original Thermo Detonator®, but it’s actually a completely different take on what a fat burner is.
Thermo Detonator® is very heavy on the stimulants, almost to a fault in fact. The stim-free option contains CLA, L-Carnitine, Green Tea Extract (caffeine free of course) and Dihydrocapsiate (from chilli peppers – very similar to capsaicin from cayenne pepper).
CLA (Conjugated Linoleic Acid) is a fatty acid that showed promising results for fat loss in animal studies, but unfortunately these results were not consistent in research on humans. The average extra weight lost from taking CLA over a 6 month period has been estimated at about 1.5kg compared to a placebo.
The green tea is still fantastic for weight loss despite the lack of caffeine. Green tea contains catechins which are strong antioxidants and can increase the rate at which you burn calories.
Thermo Detonator® Stim-Free is a solid option, but the inclusion of CLA lets it down somewhat. If you’re a diehard Grenade® fan, you should give it a go.
And that’s it – the best stim-free fat burners in the UK in 2020. We expect more stim-free products to launch over the next 12 months so we look forward to finding out if Performance Lab® can hang on to the top spot.
Stay tuned for the latest reviews and news on all things supplements and sports nutrition!