Updated: - Site operated by Leptigen

Cellucor CLK Review - Does This Weight-Loss Supplement Actually Work? Are a fad ingredient and adverse effects deal breakers?

By Summer Banks on Sep 07, 2016
Cellucor CLK Review

If you want the bottom line on Cellucor CLK, give me just two minutes of your time. We did one of our comprehensive reviews, examining the side effects, ingredients, clinical research and level of customer service. Plus we investigated hundreds of user comments and dieter experiences from all over the web. Finally, we summed up all of the facts and details to give you the information you need.


What You Need To Know

To begin, Cellucor CLK is one of several supplements available in the Cellucor product line. This supplement is marketed as a “stimulant free” fat loss formula that contains Slimpro Technology. According to the company website, Cellucor CLK helps you tone and sculpt your body, while getting rid of unwanted fat. You need to take three softgels in the morning and again in the afternoon. This product contains conjugated linoleic acid (CLA), L-carnitine tartrate, Razberi-K raspberry ketones and Slimpro protein.

Cellucor CLK has been available since at least 2013, and this supplement can be purchased conveniently through the official website. Both women and men can use product, and there are a few positive customer reviews posted online, but read on…

Fad Ingredient – “Something to Think About?”

One Cellucor CLK ingredient is the first concern we had. According to our Research Editor, “This supplement contains raspberry ketones as the key ingredient to help break down fat cells. However, there is no clinical research that supports this as an effective fat loss aid.”

“I followed the instructions, but it doesn’t work for me at all. Somehow my weight increased after I used this item,” said one customer.

“I noticed zero changes in my weight, even though I maintained my diet exactly as before,” mentioned another user.

Adverse Effects – “Uh Oh”

After reading some online customer reviews it’s obvious that Cellucor CLK side effects may be a problem. In fact, one person stated, “Do not buy this product! This product gave me extremely bad explosive diarrhea. I was literally running to the bathroom every 2 hours to paint the toilet bowl.”

“I only took one in the morning and it made my stomach burn so much,” revealed another customer.

Our research has shown if there is some particular part of a fat burner supplement or diet product that is especially bothersome or concerning (fad supplement ingredient, adverse effects, high cost) the odds of lasting weight-loss success are slim. This means if Cellucor CLK does in fact cause negative reactions, this could be problematic.

Any Real Science?

We at DietSpotlight like to see some real science that backs up the diet product and the ingredients it contains for weight-loss. However, there is no clinical research presented on the official website to support Cellucor CLK. In fact, the key ingredient, raspberry ketones, has not been proven to help with fat reduction at all.

The Bottom Line – Does Cellucor CLK Work?

Now the moment you’ve been waiting for: our bottom line on Cellucor CLK. Well, we like that it is easy to use anywhere and it does contain some natural ingredients. There are even a few positive customer comments posted on the official website. Then again, we have some concerns because it’s not actually supported by any clinical research. Moreover, we’re leery about the adverse effects that some customers have experienced.

If you’d like to shed more weight, then we encourage you to select a product that does not cause any unpleasant adverse effects, contains clinically proven ingredients for weight-loss and gives you plenty of bang for your buck.

Among the best products we’ve seen in 2016 is one called Leptigen. This product offers a proprietary blend of four ingredients, which have been shown in published scientific studies to help improve fat loss and elevate metabolism. We have not found any mention of harmful adverse effects and comments around the web indicate people are seeing substantial results.

The makers of Leptigen are so excited about their product they’re offering a Special Trial Offer, which is very reassuring.

Get Your Sample Today »
About the Author:

Summer Banks is an ISSA-Certified Fitness Nutrition Specialist and has reviewed over 2000 diet products. She has years of nursing training, experience as a manager responsible for 15 supplement brands, and completed coursework on Food and Nutrition from Stanford University. full bio.

How Does Cellucor CLK Compare?

Previous Cellucor CLK Review (Updated June 25, 2012):

What You Should Know

Cellucor CLK is a new weight loss supplement from Cellucor. The supplement is not the company’s first attempt at formulating a dietary aid that boosts weight loss and this try is not exactly a stellar attempt. Aside from Raspberry Ketones, the formula provides not proven weight loss benefits for the average dieter, but it does taste like raspberries.

List of Ingredients


  • Conjugated Linoleic Acid
  • L-Carnitine
  • Raspberry Ketones
  • 7-Keto DHEA

Product Features

There are only four ingredients listed for Cellucor CLK. The first is conjugated linoleic acid, commonly referred to as CLA. CLA was an extremely popular weight loss ingredient about 10 years ago, but soon science reported no real weight loss benefits for the average dieter. That didn’t seem to stop companies from adding CLA to supplements and smacking a weight loss claim in the product description. According to studies, CLA may boost lean muscle mass for athletic users and concurrently reduce body fat, but the same cannot be said for average dieters. CLA has been associated with stomach discomfort and gastrointestinal side effects.

Raspberry ketones are the new hot ingredient thanks to Dr. Mehmet Oz supporting the supplement. According to the website for Dr. Oz, raspberry ketones have some support via in-vitro and animal studies, but at no point have human studies been completed on the extract. We searched PubMed and found no indication of any human clinical studies.

Rounding out Cellucor CLK is 7-Keto DHEA. According to WebMD, there is no evidence supporting weight loss when taking 7-Keto DHEA. We were unable to find any clinical studies supporting weight loss claims associated with 7-Keto DHEA.

See Our Featured


  • All ingredients for Cellucor CLK are listed online.
  • The product is available for sale online.
  • The softgels are raspberry flavored.


  • Contains no proven weight loss ingredients.
  • May cause stomach discomfort.
  • May be playing off raspberry ketone popularity.


If at least one of the ingredients in Cellucor CLK was proven to spark weight loss or boost thermogenesis we could throw Cellucor a bone on CLK, but we found no evidence any of the ingredients in this formula are worth the $70 you’re paying for just one bottle. The flavoring is a nice touch, but it won’t make Cellucor CLK a better supplement. With additional research, raspberry ketones may be proven to support weight loss in humans, but a raspberry ketone supplement is far less expensive than Cellucor CLK.

Cellucor CLK Questions & Answers:

We read and digested all the user comments about Cellucor CLK and condensed into this helpful FAQ.

What are the side effects of Cellucor CLK?

According to some customer reviews, Cellucor CLK side effects may include severe diarrhea, stomach pains, heart burn, indigestion, and nausea.

What are the ingredients in Cellucor CLK?

Cellucor CLK ingredients include l-carnitine tartrate, Razberi-k raspberry ketones, Slimpro protein hydrolysates of blue whiting, gelatin, glycerin, soy, purified water, beeswax, sorbitol, maltodextrin, flavors, and coloring dyes.

Does Cellucor CLK work?

There is no clinical research to support the claim that Cellucor CLK supports or promotes weight-loss, nor do any of its ingredients have clinical support that we could find.

If you are looking for a product with clinically tested ingredients, you should check out Leptigen.

How much does Cellucor CLK cost?

A bottle with 60 capsules costs $49.99 and a bottle with 90 capsules costs $69.99.

What is Cellucor CLK’s BBB rating?

Cellucor CLK is not accredited by the BBB.

How should I take Cellucor CLK?

It is recommended that consumers take three soft gels in the morning and three soft gels in the afternoon. It is strongly advised not to take more than six soft gels per day.

Can I take Cellucor CLK if I have a health condition?

If you are pregnant, nursing, under 18, or suffer from any kind of health condition, or take prescription medications, consult your physician before taking a weight-loss supplement, including Cellucor CLK.

What do users like about Cellucor CLK?

Customers seem to like the flavor of Cellucor CLK.

What do users NOT like about Cellucor CLK?

Customers do not like that side effects and no weight-loss results have been reported.

How do I contact the Cellucor CLK customer service?

Cellucor may be contacted about Cellucor CLK by phone at 866-927-9686. They also provide their e-mail on their website, which is support@cellucor.com. Additionally, you can check out social media platforms and the live chat.

Do I need to change my diet for Cellucor CLK?

Though it is not a requirement to change your diet while using Cellucor CLK, healthy eating habits may help aid in your weight-loss journey.

Do I need to exercise to take Cellucor CLK?

Exercise is not required for the use of this supplement, though it is recommended for the best results.

Does Cellucor CLK come with a guarantee?

Cellucor provides a 100% money back guarantee on all of its products for 30 days after delivery.

Do you know of any special deals or discounts on Cellucor CLK?

There are no special deals or discounts available for Cellucor CLK at the moment. However, one supplement customers love is Leptigen. With a high satisfaction rate, manufacturers are sure you will love it too, which is why they are offering a Special Trial Offer to all customers. Click here to try out Leptigen today.

4 User Reviews About Cellucor CLK

Leave comments below
  • 1

    I took the recommended dose between meals 2 & 3 at approximately 1pm. By 6pm, I felt a “full” sensation, which was odd since I’m on competition prep and starving all day. By 9pm I was a barfing/diarrheal mess. Everything I ate after taking the pill never digested and had just sat in my gut. Horrible product.


  • 2

    I just started taking clk to lose weight I would like to know if this product really works.
    How pounds you lose per week


    Your Namegr brown

    I would like to know has anyone experienced acne breakout or just breakouts over the body and face from using CLK. I am experiencing all of a sudden I break out over the past two weeks of taking this product and mind you I have never suffered any problems not even as a teenager. Thank you GR


    Candace (Editor)

    Acne has been sometimes reported. Anyone have any advice?


Have a comment or question about Cellucor CLK?