icon-account icon-glass

Join the community!

We'll keep you up to date with interesting news, product information and offers so you never miss out.

No boring newsletters and we'll never share your address. You can unsubscribe at any time.

Popular Products

The Lean Protein
Whey protein powder for weight-loss.
The Energy Booster
Pre/intra-workout powder with BCAAs.
The Glow Booster
Collagen supplement for skin.
#FBF0C6
Flavoured acetyl l carnitine blend. The most popular non-stimulant fat-loss supplement in the world. It works by ensuring your body is metabolising fat efficiently.
Flavoured acetyl l carnitine blend. The most popular non-stimulant fat-loss supplement in the world. It works by ensuring your body is metabolising fat efficiently. The Define Booster by Innermost Ambar Driscoll smiling and looking confident for Innermost The Define Booster white powder - acetyl l-carnitine supplement by Innermost
Flavoured acetyl l carnitine blend. The most popular non-stimulant fat-loss supplement in the world. It works by ensuring your body is metabolising fat efficiently.
The Define Booster by Innermost
Ambar Driscoll smiling and looking confident for 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. Acetyl-l-carnitine is the most popular non-stimulant fat-loss supplement in the world. Combined with vitamins B6 and B12, the product works by ensuring your body is metabolising fat efficiently.

The Define Booster

Juicy Orange | 120g

£29.95 £29.95

Earn Reward Points

Loyalty Program

Earn 5 Reward Points for every £1 you spend when you open an Innermost account. Then, exchange points earned for money off your orders. It's as easy as that! Sign up.

Product Highlights

Active Ingredients

For every serving of The Define Booster: Acetyl l-carnitine (2g), vitamin B6 (1.4mg, 100%*), vitamin B12 (2.5µg, 100%*)

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

This product is vegan, cruelty free, gluten free, lactose free, soy free, halal, suitable for kosher diets, non-GMO, and free from all 14 major allergens. Furthermore, the product contains natural flavours only with no artificial fillers, bulking agents or colours. We use a tiny amount of sucralose to add a little sweetness to the product. Sucralose is the safest and most widely tested zero-calorie sweetener on the market and approved by all food standard agencies in the world.

How And When To Use

To be taken during the day, once a day.

Directions: Mix 2g (1 flat teaspoon) with around 250ml of cold water and stir until dissolved. 

Serving Sizes: One bag of The Define Booster contains 60 servings if following the above directions. That's 2 month's worth if consuming daily.

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

Giving Back

For every order you place with Innermost, we donate a meal to a child in need.

Innermost is proud to partner with The Akshaya Patra Foundation who provide school meals to children in need supporting their ability to get an education. Learn more here.

Metabolise fat for energy
A weight loss supplement that's science backed. Acetyl l-carnitine helps the body break down fat cells to be used as energy, without any weird side effects.
Improve tone and definition
Use as part of a healthy diet and regular exercise to help you tone up and define.
Support energy and performance
A natural energy booster, acetyl l-carnitine is able to cross the blood-brain barrier to provide mental benefits as well as physical.
Easy to use
Simply add to a glass of water and stir until dissolved to enjoy as a refreshing drink at any time of day.

User trials

*Results based on 59 participants surveyed over a 30 day period. Participants were requested to log a diary and complete a survey at the end of the month.

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.

Do I have to take it alongside a workout?

You don’t have to be working out to take The Define Booster - you can take it whenever you want, even on non-workout days.

What does The Define Booster taste like?

The Define Booster is one of the first flavoured acetyl-L-carnitine products on the market. We've added natural flavours to give it a refreshing juicy orange taste. Think orange squash.

Can I mix it with other products?

You can absolutely take The Define Booster alongside any other Innermost product.

Why should I believe this product will work?

All our products have been formulated by expert nutritionists using science-backed research supported by peer-reviewed clinical trials. You can read some of these clinical studies by clicking here. Our products work because we focus on the following things above all else - the ingredients we use, the quality of these ingredients, their concentrations and how well they're absorbed by your body. Our unwavering commitment to that approach means what you get are the highest quality, cleanest supplements in the world today - without any BS.

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.

Our ingredients

 

With so many “miracle” ingredients being touted out there, it can be hard to know what really works. We believe evidence-based ingredients are the best way to better health. With decades of clinical studies showing how the active ingredient in this product can encourage the metabolisation of fat during physical activity, ensure efficient use of energy, and help improve tone and definition, we're confident that you’ll thank us later.

Per Serving:

Acetyl L-Carnitine

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. References > 1, 2.

Vitamin B

Vitamin B6 (1.4mg, 100%*) and Vitamin B12 (2.5µg, 100%*): For the reduction of tiredness and fatigue and normal energy-yielding metabolism. These also play a role in maintaining hair and skin health, and a regulated nervous system. 

Allergens: None. 

Per Serving:
Acetyl L-Carnitine (2g)
Origin:

China

About:

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.

References:

[1] [2]

Vitamin B6 (1.4mg, 100%*) and Vitamin B12 (2.5µg, 100%*)
Origin:

Germany

About:

For the reduction of tiredness and fatigue and normal energy-yielding metabolism. These also play a role in maintaining hair and skin health, and a regulated nervous system.

References:

[3] [4]

Allergens: None. 

Learn More:  6 Habits to Melt Fat Fast
Learn More:  5 Reasons Why You Aren't Getting Leaner

Why it's special

Acetyl L-Carnitine

Acety l-carnitine is a substance natural to the body that serves an important role in the burning of fat for energy, and ferrying fatty acids across the walls of the mitochondria, where they are oxidised and turned into energy. On its return trip from inside the mitochondria, it brings back acetyl groups and other small fragments produced in fatty acid oxidation. Carnitine's role in fat metabolism leads it to affect, in some degree, all the other energy metabolism in the cell, including the burning of carbohydrates. Some researchers have suggested that its important role in the burning of fat also makes it useful in diets for weight loss.

Vitamins

Vitamins B6 and B12 are essential for converting food into energy, supporting metabolism, and maintaining healthy circulatory and nervous systems. Their roles in energy production and metabolism make them vital for weight loss efforts, as they enhance the body's ability to utilise nutrients efficiently, aiding in the overall weight management process.

When should I use the product?

The Power Booster anytime during the day or before your workout.
The Energy Booster right before and/or during your workout.
The Wellness Blend works well as a morning/afternoon pick-me-up.
The Define Booster anytime during the day but morning works well.
The Glow Booster anytime during the day but morning works well.

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 Wellness Blend will last 50 days.
The Define Booster will last 60 days.
The Glow Booster will last 20 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.

What sort of testing do you do?

We go over and above to ensure you get the best quality and safest products possible. We only use ingredients that have a visible supply chain, and our manufacturing facilities are approved to the highest regulatory standards. Once we receive ingredients, we batch test every single one before it gets approval to go into the manufacturing process.

Ready To Buy

US VS THEM

Innermost VS Competitor
  • Formulated by leading nutritionists.
  • Science-backed and research-based.
  • High-quality ingredients that work.
  • Bioavaliable nutrients.
  • No binders, fillers or preservatives.
  • Focus on quality and safety.
Competitor
  • Generic off-the-shelf formulations.
  • Driven by the latest fads and gimmicks.
  • Cheap and less effective ingredients.
  • Poorly absorbed nutrients.
  • Unecessary preservatives and additives.
  • Buy it cheap and stack it high.

Customer Feedback

Customer Reviews

Based on 26 reviews
65%
(17)
19%
(5)
12%
(3)
0%
(0)
4%
(1)
v
victoria Davis
Good product

Only been using this for just over a week, not really seen any results in my weight but that could be a bit of muscle gain. On the other hand I’ve noticed that I have more energy And it’s sustained throughout the day.
I take it with water like it states on the packaging, it mixes well but tastes and smells horrible so would recommend having it with something flavoured.
Don’t know if it’s just mine but the powder is very clumpy.
Overall I would recommend this product.

L
Luisa Lajolo

A bit acid. But I like. I haven’t noticed any change yet.

Thanks for the feedback! We hear you about the slight acidity and appreciate your liking it. Results can take time, so stay consistent. If you have any questions or need assistance, feel free to reach out.

S
Sarah Buddle
Sweet

Drinkable

Afternoon,

Thank you for taking the time to leave a review, we appreciate your kind words!

Best,
Hannah

H
Howard Carpenter
Orange booster very efficient at hydrating

On first impression this had quite a strong potent smell from the bag but once it’s mixed with water it tastes like a hydrate tablet and tastes lovely. Perfect for post workout hydration and a supplement to other innermost proteins.

Thank you so much for this lovely feedback Howard!

W
Winnifred M
Define Booster - A great addition to your weightloss journey

This is a great accompaniment to my exercise program. I'm so pleased with the changes to this product (where it used to taste bitter and needed getting used to!). Whilst the outcome is still effective, the flavour has made it more pleasant to consume on a daily basis.

Hey Winnifred, this is such a great review to read, thank you so much for sharing.

Ready To Buy
"Innermost protein is as smart as it is delicious."
"Known for their tailored nutrition for body and mind."
"Favoured by athletes across the globe."
"The best protein shakes for a post workout pick me up."
"Known for redefining performance supplements into cleverer supportive measures."
"You'll have to take our word that it's hands down delicious."
"Filled with all the good stuff... Oh, and it tastes great too."