Insane Labz Slender Fat Burner Review


  • L-Carnitine can slightly promote fat loss
  • L-Carnitine reduces muscular damage & fatigue


  • Raspberry Ketones arent effective at promoting fat loss
  • Dandelion Extract can make you dehydrated
  • Missing key fat burning nutrients (eg. Green Tea Extract)
  • No ingredients to suppress your appetite
  • Not good value for money

See Your Best Options In Our
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- Top 3 Fat Burners For Men Page -


About The Product

Slender is a fat burner made by Insane Labz. It costs $44.95 for 30 serving containers, with a serving size of 2 capsules per day; this isnt a good serving size, as studies have shown 3-4 capsules daily to be optimal at keeping your body fuelled with nutrients all day.

Insane Labz have jumped on the bandwagon of increasing non-stimulant products with Slender.

We believe this rise is a result of companies adding large dosages of caffeine into their supplements. But as long as you consume under 100mg Caffeine per capsule with fat burners, youll be safe from side effects while experiencing a stable boost in energy levels.

Anyway, well analyze Insane Labz Slenders nutrient profile for you in the next section. But first, well tell you more about the company behind it.

Who are Insane Labz? 

Insane Labz are a USA-based supplements company thatve gained a good reputation from their pre-workouts. While theyre not as well known for their testosterone boosters and fat burners, they do still produce them.

But one thing we dont like about this company, is that they add every ingredient in every product into proprietary blends (well explain why in the next section).

As youre here to learn more about Insane Labz Slender, lets stop wasting time and get into this review below…

Insane Labz Slender Ingredients Explained

Insane Labz Slender contains 8 ingredients overall; this is a good amount to have in a supplement, as we know from experience that supplements containing too many nutrients are usually under-dosed.

But the problem here is, every ingredient is part of a proprietary blend. So youre not shown the dosages of each ingredient inside Insane Labz Slender anyway (well expand on this below).


Proprietary blends are mixtures of numerous ingredients thatre only shown to you as 1 quantity. As you can see from the Slender Blend on Insane Labz Slenders ingredient list, the overall amount is 725mg - but youre not shown the dosages of each ingredient inside such as Raspberry Ketones.

This increases your risk of side effects, and also makes it uncertain whether this fat burner will work. For this reason, we try to avoid any supplement that contains proprietary blends.

Anyway, now that you know why we dont really like proprietary blends, well take you through each ingredient inside Insane Labz Slender.

By the end of this review, youll know exactly how safe and effective this fat burner really is.


Heres Everything You Need To Know:

L-Carnitine Tartrate 

This is probably the most common form of L-Carnitine youll find; its proven to reduce muscle fatigue and damage, while increasing your focus in the gym.

For this reason, we consider L-Carnitine Tartrate to be a key addition to a pre-workout supplement. But remember that this is a fat burner supplement.

There are different forms of L-Carntine, with Acetyl-L-Carnitine being the best for promoting fat loss. The bad news is that L-Carnitine Tartrate hasnt been shown to be very effective at helping you lose fat.

So while its still the best ingredient inside Insane Labz Slender, its not the best; we would have preferred to have seen a tried-and-tested nutrient such as Green Tea Extract instead here.

Juniper Berry 

In case youre wondering, this is the same stuff youll find in your gin and tonic. Its great for delivering antioxidants and enhancing the taste of your alcoholic beverage, but thats about it.

Unfortunately, Juniper Berry hasnt shown to have any impact on your fat loss journey at all. So its a good bonus addition, but Insane Labz should have made sure they added key nutrients first.

Dandelion Extract 

You might be wondering why Dandelion Extract has been added into Insane Labz Slender. But companies add this ingredient as its a diuretic, meaning its able to effectively dehydrate you - helping bodybuilders get drier on stage.

So whats the problem? Well, Dandelion Extract can cause serious dehydration if the consumer doensnt know that its a diuretic; as Insane Labz havent mentioned this in their product description, were assuming that not many people will know.

For this reason, we consider Dandelion Extract to actually be a risk here. And it can even fool people into thinking their losing weight, when really its simply water weight that theyll pack back on after they stop consuming Dandelion Extract.


L-Carnitine Fumerate

Remember that we mentioned theres many different forms of L-Carnitine? Well, this is another one.

The worst thing is, not much is known as L-Carnitine Fumerate, so nothing has been proven - making it an unreliable ingredient.

Ultimately, when youre buying a supplement, you want guaranteed results. Unfortunately, L-Carnitine Fumerate might not help you achieve your fitness goals.

Raspberry Ketones 

If theres one ingredient that we dont like, then its Raspberry Ketones; it gained media attention for being some kind of miracle ingredient for fat loss.

Since then, companies latched onto this and began adding Raspberry Ketones into their supplements to fool customers. However, studies have proven that this doesnt promote fat loss at all.

Not only that, Raspberry Ketones are chemically treated with Synephrine, so it comes with the risk of side effects too. For this reason, we advise that you try to avoid this ingredient when you can.

Celery Seed Extract 

Not much is known about Celery Seed Extract, but its believed to have antioxidant properties due to containing Sedanolide. Its also been traditionally used as a diuretic too.

Ultimately, this adds to your risk of becoming seriously dehydrated. Again, we would have preferred to see a key ingredient proven to promote fat loss, such as Green Tea Extract instead.

White Willow Bark 

White Willow Bark Extract is always a strange addition to any supplement, as its mainly used as a painkiller; its also suggested that it can replace aspirin in certain things as a result.

For this reason, we dont consider this to be a necessary addition to Insane Labz Slender here.


See Your Best Options In Our
»Best Fat Burners For Women Page«
- Top 3 Fat Burners For Men Page -

Side Effects

The main concern we have with Insane Labz Slender, is that it contains Dandelion Extract and Celery Seed Extract; these are both diuretics, which can cause serious dehydration to those who arent aware theyre diuretics.

As Insane Labz dont clearly state that it contains diuretics, we believe that this is a possibility.

Not only that, Insane Labz Slender contains Raspberry Ketones, which has been chemically treated with Synephrine - this means it can cause side effects that well bullet point below.

Heres the potential side effects from taking Insane Labz Slender: 

  • Serious dehydration (Dandelion Extract and Celery Seed Extract)
  • Jitters (Raspberry Ketones)
  • Increased Blood Pressure (Raspberry Ketones)
  • Rapid Heartbeat (Raspberry Ketones)

Insane Labz Slender Review Conclusion

Ultimately, we feel that this review has been quite critical.

But weve been as fair as we can be; Insane Labz doesnt contain any key fat burning nutrients proven to work, and can even put you at risk of side effects.

If it had contained ingredients such as Green Tea Extract and Cayenne Pepper Extract, it would have been a much more positive review.

However, we cant recommend Insane Labz Slender to you, as we dont believe its likely to help you burn fat.

Insane Labz Slender Fat Burner Review

Bottom Line

Insane Labz Slender doesnt contain the necessary nutrients to promote fat loss, but can put you at risk from side effects (in our honest opinion).

For this reason, we dont believe that it can compete with the highest rated fat burners available right now.


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