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A pouch of The Define Booster - acetyl l-carnitine supplement by Innermost
A pouch of The Define Booster - acetyl l-carnitine supplement by Innermost
A pouch of The Define Booster - acetyl l-carnitine supplement by Innermost
Ambar Driscoll smiling and looking confident for Innermost
Pouches of The Define Booster - acetyl l-carnitine supplement by Innermost
The Define Booster white powder - acetyl l-carnitine supplement by Innermost

The Define Booster

Definition done properly.

To decrease body-fat you need the right nutrients. That’s where this product comes in. The most popular non-stimulant fat-loss supplement in the world. It works by ensuring your body is metabolising fat efficiently. Live life in High Definition.

The Define Booster

Unflavoured with a slightly bitter taste | 200g

£24.95 £24.95

Product Highlights

Active Ingredients

For every serving of The Define Booster: Acetyl L-Carnitine (2g).

Scroll down to learn about these ingredients and how they benefit you.

How And When To Use

To be taken during the day, once a day.

Directions: Mix 2g (1 flat teaspoon) with around 200ml water or juice in your Innermost shaker bottle, or simply add 2g to your pre or post-workout protein shake. Unflavoured acetyl l-carnitine does have a bitter and citric taste so mixing it with orange juice or lemon water works well.

Works Well With: The Tone Capsules to raise your metabolism and support healthy fat-loss.

I’ve never been able to see muscle definition…


Gaining definition can seem like an unattainable goal.

But it doesn’t have to be. If you’ve been working hard to see results, and just want an extra push in the right direction, then look no further.

The Define Booster is one of our most popular products for a reason. Formulated by leading nutritionists, it's been crafted to metabolise fat for energy, support endurance, and even boost memory and learning. Start seeing the lean muscle definition you’re looking for. Because reaching your fitness goals doesn’t have to be impossible.

Innermost is awarded The Game Changer Award. The sands are shifting in the supplements industry. One brand stands out most, Innermost. We now expect more from our supplement products and Innermost is well ahead of the curve.

Best kept secret


Scientifically proven to encourage the metabolisation of fat during physical activity, ensuring efficient use of energy, and helping improve your tone and definition. It's what's inside that matters.

Per Serving:

Acetyl L-Carnitine (2g): One of the most popular non-stimulant fat-loss supplements on the market today. A non-essential amino acid found naturally in the human body, necessary for transporting fat to the body’s power-generating mitochondria for use as energy during physical activity. Without carnitine, we wouldn’t be able to use fat effectively as a source of energy, which could result in the body having to break down muscle instead. The key benefit of the acetyl form of carnitine is that it can cross the blood-brain barrier to improve mood, learning and memory as well.

Allergens: None. 

Be the best version of you


We use cutting-edge science and research, as well as best practices from Ayurvedic and Asian medicine, to craft the smartest nutrition products possible that give you the results you told us you're looking for. Free from additives, artificial colours, fillers and GMO nasties. Because everyone deserves to live life better.

When should I use the product?

The Power Booster anytime during your day but we'd recommend before your workout. The Energy Booster right before or during your workout. The Detox Booster anytime during your day but we'd recommend it as a morning or afternoon pick-me-up. The Define Booster anytime during your day but we'd recommend in the morning.

How many servings do I get?

Based on taking each product every day as recommended: The Power Booster will last 60 days. The Energy Booster will last 30 days. The Detox Booster will last 60 days. The Define Booster will last 100 days.

Can I mix and match products?

Yes, absolutely. We developed all our products so that you can mix and match any of them depending on your individual goals and needs. You will get the benefits of each of them regardless of whether you're taking them alone or with any of our other products.

Love this supplement. I have a teaspoon every day and feel it's really boosting my metabolism and giving me a mental lift!

Lucy A, Verified Customer

Customer reviews

Customer Reviews

Based on 16 reviews
50%
(8)
31%
(5)
19%
(3)
0%
(0)
0%
(0)
H
H.
Great product to mix into smoothies

Great product, doesn't taste brilliant on it's own but it's easy to mix into smoothies and porridge.

P
P.
Strange but good!

I weirdly love the taste of this - it’s very bitter, exactly like a big squeeze of lemon juice in a glass of water. I have it first thing in the morning and it wakens my taste buds. I’m not hugely aware of losing weight or becoming more defined with it but I’ve added it in to my fitness regime and overall I’m seeing differences.

L
L.U.
Not sure

I'm not sure about this one. Although if I'm honest I don't take it daily. I have it with my protein shake which is every second day. I am very slowly getting toned but I think that's simply down to the fact that I'm finally moving after months of not. The taste is quite pungent and in the pack reminds me of salt and vinegar crisps, but hides well in the shake.

L
L.k.
Gives an energy boost

Have it first thing in the morning in a glass of cold water !
It's a strong taste but seems to be working :)

J
J.T.
Strong taste - very bitter

Too early to tell if this product is beneficial. Seems good value for money though, and it's easy just to fix up as a quick afternoon boost. It tastes like a salty lemon, but a quick shot is easily done.

D
D.M.
Seeing improvements

Ordered this a few weeks ago and already seeing improvements. Down from 20% body fat to 17% ☺️