Alpha Fat Burners

Siren Labs Neuro Lean Review

A product by Siren Labs

Overall Rating:


Positives Negatives
  • Contains Caffeine and Green Tea
  • Poor Servings
  • Proprietary blends
  • Potential Side Effects
  • Some ineffective ingredients

Review Overview – What does Neuro Lean do?

Created by Siren Labs, this is an all natural fat burner that has been seen to promote:

  • Energy Levels
  • Focus
  • Fat Loss
  • Water Loss


But how well does it really work?

In this review, we look closer at Neuro Lean to see how well it really works.

This is what you need to know:

How are the servings?

Could be better.

With only 2 servings a day, this isn’t your best option for effective fat loss.

For the best results you need to give your body a constant supply of the nutrients it needs to keep burning fat throughout the day.

The effects of each serving wear off after a couple of hours – for the best results you need a constant supply throughout the day, between 3 – 4 servings – double what you’ll find in this product by Siren Labs.

What about the ingredients in Siren Labs Neuro Lean?

Not great.

The first problem here are the proprietary blends. This is when a supplement bundles together numerous nutrients under the same dosage. The problem with this being you don’t know how much you’re getting of each individual ingredient or how effective it will be overall.

The second problem are the side effects. There are numerous nutrients in this product that have been linked to causing negative side effects. It could severely impact your fat loss journey.

Here’s what you need to know about the main ingredients:siren-labs-neuro-lean-side-effects


Arguably one of the best natural stimulants.

Caffeine has been seen in numerous studies to help promote energy levels and metabolism.

It can also help boost power output.

Citrus Aurantium

Also known as Synephrine, Citrus Aurantium is one of the poorest fat burners out there.

Thought to help with fat loss and energy levels – however, studies have shown that it has little to no effect when it comes to actual benefits.

However many users, and studies have shown various side effects. More on that in the next section.


Not a good option either.

Phenylethylamine has been thought to help with mood and motivation, due to its ability to promote happy hormones like dopamine and serotonin.

However, studies have shown that when orally supplemented Phenylethylamine is broken down too quickly to have any proper effects.


Another risk.

Although Yohimbe is one of the better options for appetite suppression, which can reduce hunger cravings, several users have reported side effects during supplementation.

More on that later.


One of the better choices for focus.

Choline has been seen to increase focus and learning, all while reducing anxiety.

It’s a good option for staying focused in the gym, but not ideal when it comes to helping with actual fat loss.


PS is one of the better brain boosters out there.

Studies have shown that PS do 4 main things: promote focus, memory and mood while reducing cognitive decline.

It’s a good, all over brain booster, but again, doesn’t help with fat loss.


A really poor choice.

DMAE is a brain booster that has been linked to reducing cognitive decline – however studies have shown that it isn’t actually that effective.

In reality the results from DMAE are pretty unreliable, and not only that – it may even cause side effects.

More on those later.

Ginkgo Biloba

This one of the poorer nootropics (brain boosters).

Ginkgo Biloba has been thought to boost cognition, but in reality the effects are incredibly mixed.

The effects of this ingredient are so unreliable that many researchers believe that the overall effects may even be placebo.

It’s not a good option.


A diuretic that may help with water weight but not fat loss.

Dandelion has been seen to help cut down water retention in your body and shift overall water weight.

However, it doesn’t actually help with fat loss.

Water and fat are two different things and it may even cause dehydration.


A good herb for both calm and focus.

Ashwagandha has been seen in numerous studies to help reduce anxiety and lower the stress hormone cortisol.

This may help with focus, but not with overall fat loss.

Rhodiola Rosea

Again, another herb that may help with mood and motivation – but does not promote fat loss.

Rhodiola Rosea has been seen in numerous studies to help lower the effects of both anxiety and depression.

This may help promote feelings of well being and may help you feel better during your cut – but won’t directly contribute to fat loss.siren-labs-neuro-lean-side-results

Ingredients Bottom Line:

From this nutrient profile, it’s clear to see that Neuro Lean doesn’t have the best fat loss profile you can come across.

Many core thermogenics like Green Tea, Green Coffee Bean and Cayenne Pepper are missing from this blend – and there has been no attempt at using any effective appetite suppressants like Glucomannan.

Not only that, there are several ingredients in this product that may cause side effects.

It’s definitely not shaping up to be a good option.

Side Effects

There are several concerns in Neuro Lean when it comes to side effects: Synephrine, Yohimbe and DMAE to name just a few.

Synephrine has been reported in numerous cases to cause the following side effects (especially when mixed with caffeine):

  • Headaches
  • Nausea
  • Risk of High Blood Pressure
  • Increased Heart Rate
  • Dizziness

It’s not your best option while cutting, whereas Yohimbe has been seen to cause anxiety, hypertension and gastrointestinal distress.

Finally DMAE has been seen to cause birth defects in expectant mothers – and it is still being researched.

The full effects of this addition are still unknown – and we strongly recommend staying away from it.

Is there anything better than this fat burner?


We’ve scoured the market for the best fat burners that promote:

  1. Thermogenic Calorie Burning
  2. Energy Levels
  3. Fat Loss
  4. Appetite Suppression

And we’ve narrowed it down to just three.

To see what works best for men, and what works best for women, check out the top 3 rated fat burners on the market in the links below:

Best Fat Burners for Men
Best Fat Burners for Women

Siren Labs Neuro Lean Review Conclusion

On the whole, this isn’t the best fat burner on the market.

From this review, here’s what you need to know about Neuro Lean;

  • Poor Servings – Not enough throughout the day to ensure day long fat burning.
  • Proprietary Blends – You don’t know how much of each ingredient you’re getting or how effective it will be overall.
  • Ineffective ingredients – Many of the nutrient used lack the proper clinical studies to support their claims.

As you can see, it’s not your best option.

To see what our readers, and now editor, are recommending as the most effective fat burner – check out our full review of our current #1 in the link below:

What I'm using at the moment - Instant Knockout

I tried Instant Knockout for 3 months and went from skinny-fat to absolutely SHREDDED.

You can see my results and why this is our #1 Fat Burner here.

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