Cellucor CLK

Cellucor CLK is a non-stimulant weight loss aid available in the US that combines several well-known ingredients with a ‘marine natural ingredient’ called SlimPro.

Below we take an in-depth look at Cellucor CLK to see whether the diet pill can aid significant weight loss.

Cellucor CLK Pros

  • 100% money-back guarantee

Cellucor CLK Cons

  • Ingredients have little or no human-based clinical evidence
  • Expensive, especially when ordered from the manufacturer
  • Need to consume 6 capsules per day
Watchdog Rejected Diet Pills

Cellucor CLK Review

Cellucor CLK Facts

  • Manufactured By Cellucor.
  • 60 or 90 capsules per bottle.
  • Very expensive.

Cellucor CLK is a non-stimulant weight loss aid manufactured by Cellucor. It promises to aid toning and sculpting, without the side effects that are common in stimulant-based weight loss aids.

Cellucor is a brand owned by Woodbolt Distribution LLC, who are based in Texas, USA. The company recruit through the name NutraBolt, and own several supplement brands, including Neon Sport (a sports nutrition range for athletes), Royal Sport Ltd (top-shelf stimulant based nutrition brand), Cavalier (a range of supplements for men, including testosterone boosters and sexual health supplements), and Cellucor. The company can be contacted using the information provided on the Cellucor official website’s contact us page.

How to Take Cellucor CLK

Take one serving (3 softgels) in the morning and one serving (3 softgels) in the afternoon. Do not exceed 6 softgels per day, use only as directed.

Cellucor CLK Concerns:

  • Ingredients have little or no human-based clinical evidence.
  • Expensive especially when ordered from the manufacturer.
  • Need to consume 6 capsules per day.

What Does Cellucor CLK Claim To Do?

Cellucor, the manufacturers of Cellucor CLK, have provided the following descriptions of their product’s benefits.

  • Four All-Star Ingredients
  • Now featuring Slimpro
  • Innovative Softgel Delivery
  • Sweet Raspberry Aroma
  • Toning and Sculpting Formula

Slimpro® Protein Hydrolysates of Blue Whiting (Micromesistius poutassou): Slimpro® is a naturally derived ingredient that helps the body trigger the feeling of satiety to control appetite.

L-Carnitine Tartrate: The transporter—L Carnitine is an amino acid that plays an important role in transporting fatty acids for energy.

Razberi-K®: Raspberries are considered a super food. Besides the obvious benefits of enjoying this fruit, raspberries contain a ketone or compound that may support healthy weight loss by helping to break down fat. Razberi-K® makes reaping the benefits simpler by packing ketones into one dose.

CLA (Conjugated Linoleic Acid) helps your body use food for fuel while also supporting lean muscle development.

So What Is Cellucor CLK and What Are The Ingredients?

The ingredients used in Cellucor CLK are provided below. The ingredient quantities provided are per serving of three capsules. Each serving of three capsules contains 25 calories.

  • CLA Conjugated Linoleic Acid 1.7 grams: Naturally found in dairy products, beef and safflower oil, conjugated linoleic acid may help to reduce body fat, but may not cause changes to body weight. The average daily diet provides between 15 and 174 mg of conjugated linoleic acid, but studies have used much higher levels. Human studies of CLA have produced contradictory results, and it is described as not only a relatively poor fat burner, but also an unreliable one.

Stimulant Free Toning Blend 1014 mg

  • L-Carnitine Tartrate: One study found that supplementation of L-carnitine, L-tartrate reduced muscle tissue damage from exercise and sped up recovery time.
  • Razberi-K raspberry ketones: Although it can be extracted from raspberries, as the name suggests, the majority of raspberry ketones used in supplements is lab-synthesised, as this is a more cost effective option. Whilst there is a small amount of evidence that raspberry ketone can cause weight loss in rats, there have never been any human trials on the potential weight loss effects of raspberry ketone.
  • SlimPro protein hydrolysates of blue whiting (micromesistius poutassou): Described as a ‘natural marine ingredient’, this fish extract is described as follows on the official website.
    ‘Taken daily before meals, Slimpro® increases the production of CCK and GLP-1 in the body, thus amplifying messages associated with a decrease of food intake. Promising results were reported from in vivo et in vitro trials of these molecules that may control food intake.’

So What Does All This Mean?

Raspberry Ketone has never been tested in humans for weight loss purposes, and so it is unknown whether the promising results seen in test tube studies and tests in rodents would be replicated when the ingredient is consumed orally, or even what dosage should be consumed.

Whilst CLA has shown positive results in studies in rats and mice, aiding significant weight loss and acting as a fat burner, the clinical results in humans are much more varied. Some human clinical trials showed significant fat loss, improved body composition and even increases in muscle mass. However, other studies found no results or changes at all.

One review paper that pooled the results of 18 studies of CLA found that, on average, CLA caused ‘modest’ fat loss. Other reviews describe it as a relatively poor and unreliable fat burner. It may help to retain muscle mass whilst losing weight.

SlimPro is apparently an appetite suppressant, but it has not been tested in humans, only in test tube and animal studies.

Does Cellucor CLK Have Any Side Effects?

There are several ingredients in Cellucor CLK that can cause a variety of side effects.

Raspberry ketone is an under-researched product, especially in the quantities found in supplements. Whilst it is considered safe for use in food in small doses, the higher doses used in supplements could cause jitteriness and other symptoms. Some users of raspberry ketone have reported feeling ‘weak’, restlessness, insomnia, chest pains, headaches and nausea. Some people have also had allergic reactions to raspberry ketone based supplements, with symptoms including itching, rashes, trouble breathing and a racing heart-rate.

There are some potential side effects associated with the use of CLA. It can cause stomach upset, diarrhoea, nausea and fatigue. CLA can also increase triglyceride levels in some cases.

L-Carnitine Tartrate can cause side effects such as nausea, vomiting, stomach upset, heartburn, diarrhoea, and seizures. It can also cause the urine, breath, and sweat to have a “fishy” odour.

This product is only intended to be consumed by healthy adults, 18 years or older. Do not use this product if you are pregnant or nursing. Before using this product, consult with a licensed, qualified, health care professional, including but not limited to, if you suspect you have or have been treated for, diagnosed with or have a family history of any medical condition, or if you are using any prescription or over the counter medication. Immediately discontinue use and contact a medical doctor if you experience any adverse reaction to this product. Discontinue use 2 weeks prior to surgery. Do not exceed recommendations for suggested use. Use only as directed. Do not use if safety seal is broken or missing. Store in a cool dry place. Keep out of reach of children.

Any Cellucor CLK Reviews From Customers?

There are numerous customer reviews for this product on the various websites that sell the product. Below we have included a selection of them.

I bought this from GNC. I stack it with HD capsule. You take three of these in the morning and one HD in the morning. It does not specify on empty stomach or not. I take it twice/day, on a empty stomach then I eat 20 or 30 min later and drink plenty of water.The first day i took it, I had so much energy, I couldn’t be still, my hands were a little shaky cause I was moving around a lot. I felt like a kid that had nothing but sugar all day. It works I started sweating, heart was beating fast. I haven’t went to the gym yet I will be going later on today to see how it is. I also take Cellucor BCAA while working out as well. I train everyday, I’m a Veteran so I’m used to working out. I do my 30 min of cardio then weight lift and circuit train. I will see how this works for me today during my workout.

Worked excellent for my training of taekwondo + running + bodybuilding to have more energy and more power. I can train 2 times better with this than normal and also can do more!! I have a breathing problems and this help me to breath better!

I did notice that my stomach was flatter and my appetite was curbed pretty well while on this. However, it gives me the same results as any CLA formula I’ve taken, and those are much cheaper. I just got a 3 month supply of CLA for half as much as a one month supply as this. Does it work great? Absolutely. Worth the extra money? Not so much.

This is the first non-stimulant weight loss product I have tried. It was expensive and I’m not sure that it was worth it. The first two weeks taking 1 capsule 3 times a day seemed to help immensely with weight loss but after that it seemed to quit working. I’ve been on a strict diet and working out regularly.

This was my third and final try at the product. The first two times I never did a full cycle and I didn’t really watch my food…so I couldn’t give an honest review. This time I cleaned up my diet and religiously took this…Practically no results. My boyfriend has amazing results on it, so it works for some…just not for me.

I recently just went through a contest prep resulting in third place in an Australian national teen devision of the IFBB. I am a big fan of Cellucor products and during my prep i was looking for a little extra edge in aiding my fat loss. The 4 weeks i used the CLK my body fat percentage dropped from 18% down to 13%, of course with strict diet and exercise. But never the less the CLK definitely helped speed up the process. Will be a handy thing in my next prep. Great product.

So Does Cellucor CLK Work?

The clinical support for Raspberry Ketone is based upon studies in rats and test tubes, but no human studies. In theory, Raspberry Ketone could aid some weight loss, but there is no actual solid proof that the product will burn fat or raise the metabolism.

CLA does appear to have some effect upon the body, somewhat reducing fat mass and aiding muscle growth in consumers who are exercising regularly in order to build muscle. It may not result in weight loss overall, but as it may aid muscle growth, it could therefore indirectly boost the body’s metabolic rate. There is also the worry that it is an unreliable or unpredictable supplement. Studies report vastly different effects upon the body, with some noting no changes at all.

Overall, we do not believe that Cellucor CLK will aid significant weight loss.

Where Can I Buy Cellucor CLK?

Cellucor can be purchased from the official Cellucor website or from several online third party retailers.

From the official Cellucor website a single bottle of 90 capsules costs $69.99, with plus delivery charges. A bottle of 60 capsules costs $49.99 plus delivery charges. Cellucor members get free shipping. have both sizes of bottle on offer. A bottle of 60 capsules costs $39.99, whilst a bottle of 90 capsules costs $52.97. Delivery charges may apply. At the time of writing, this product was included in a Buy One Get One 50% Off offer; there is no indication of how long this offer lasts, or how often the offer reoccurs. However, regularly offer various discounts and deals on the products they sell.

A single bottle of Cellucor CLK costs $69.99 from the GNC website, or $65.99 for those who have a membership card.

What About A Guarantee

Cellucor CLK is covered by a 100% money-back guarantee when purchased direct from the cellucor official website.

All sales from are guaranteed to provide RESULTS! We understand that your investment into a Cellucor product is an important financial decision. That is why we extend a 30-day, full money back guarantee when you decide to make that investment.

We are so confident you will love the product and see transformative results that we are happy to put our money where our mouth is.

Supplements and Apparel must be received by the Results Team within 30 days after delivery.

Supplement returns are only accepted if purchased through We are unable to process returns, nor provide prepaid return labels for Third Party Retailer purchases.

Returns policies from other retailers may vary.

Watchdog Verdict

Overall we do not think that Cellucor CLK is worth the high price set by the manufacturers, especially considering the high number of capsules that consumers are required to take each day (six). A small bottle will last for a mere 10 days, and a large bottle will still only last for 15 days of use.

The ingredients list features several ingredients that have no clinical support from human-based clinical trials. Whilst theoretically some could suppress the appetite or burn fat, this is by no means guaranteed or proven.

The product is covered by a money back guarantee when purchased from the manufacturers, and offers a comprehensive returns policy that covers both opened and unopened products. Customer reviews are mixed, and it appears to work for some, whilst other consumers find no results.

Overall, we do not recommend Cellucor CLK to our readers.

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Disclaimer: Our reviews and investigations are based on extensive research from the information publicly available to us and consumers at the time of first publishing the post. Information is based on our personal opinion and whilst we endeavour to ensure information is up-to-date, manufacturers do from time to time change their products and future research may disagree with our findings. If you feel any of the information is inaccurate, please contact us and we will review the information provided.

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