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Glucomannan Review - Does This Fiber Supplement System Work? Are minimal results and safety deal breakers?

By Summer Banks on Aug 27, 2016
Glucomannan Review

Looking at some diet products can be painful, especially if there’s no backing for the formula. Let’s find out if glucomannan is in this group. We’ve heard a lot in the weight-loss community about this fiber supplement, so we conducted one of our detailed reviews, looking at the ingredients, negative side effects, scientific research, and the quality of their customer service team. We also read hundreds of commends and reviews from readers online. We then summarized and condensed to give you the info you need.


What You Need to Know

To begin with, glucomannan is a dietary fiber that comes from the konjac root. It is explained by manufacturers as an all-natural way to lose weight. It works to eliminate fats by bypassing the digestive process and reducing the caloric impact on your body. Glucomannan is primarily sold in tablet form, which means it can be consumed anywhere.

The product has been around for several years, but because it is produced by multiple companies it is difficult to find customer service, an official website, scientific research or data behind how well it works. The all natural ingredients, low cost, availability and convenience make this sound like an intriguing fiber supplement, but read on…

Lack of Results – “No Changes in Weight?”

One of the first things that concerns us about glucomannan ingredients is that it may not work. In a recent study, just 5 percent of obese patients taking glucomannan lost more than 5 pounds over an eight-week period. “At $9 per bottle, glucomannan seems like a steal,” said our Research Editor. “But the minimal results and harmful side effects make even that too much for this fiber supplement.

“Results were minimal, and way too slow, I guess you get what you pay for” said one user.

“I lost 2 pounds over an 8 week period, which isn’t enough to justify a monthly purchase,” explains another.

Harmful Side Effects – “A Concern”

Something else we noticed in multiple reviews and on medical websites was the potential for harmful side effects when taking glucomannan. Because it partially bypasses the digestive system, it can nullify the effects of different medications. It can also have adverse issues for diabetics by mitigating the results of insulin intake.

“At $9 a bottle, I was excited to try glucomannan, but once I looked at the side effects and health concerns, I threw my bottle away,” said one would-be user.

Another claimed “This fiber supplement rendered my heart medication useless. I had to stop taking it immediately to avoid further complications.”

Our studies of various health and diet products has shown that when there is something abnormally difficult or troublesome about a particular supplement or routine (cost, side effects, slow results, pain/difficulty of an exercise routine, etc.) users are more likely to give up and long-term success is rare. If glucomannan really does cause adverse reactions, this could be an issue for those attempting to lose weight.

If you are interested in using glucomannan to lose weight, we recommend that you do so without taking any other medications. If this is taken by itself, with no other medications, it may not cause negative side effects.

The Science – “Legitimate?”

Glucomannan has a scientific sounding name, but there’s very little data to be found. There are no studies proving the effectiveness of this fiber and although it’s significantly cheaper than comparable products, there’s no data proving that it matches up to proven formulas. At DietSpotlight, we emphasize science when it comes to weight-loss and when there is no proof for a particular supplement, we find that troublesome.

The Bottom Line – Does Glucomannan Work?

Ladies and gentlemen, what’s the final word on glucomannan? There was a lot to like about this one initially, like the affordability, convenience and availability. There were also a few positive comments online, proving that some people did find it possible to steadily lose weight. Unfortunately, there were a few major concerns for us and that means we’re hesitant recommending this as an effective weight-loss supplement. Glucomannan’s lack of results and science behind the product’s claims make this one that we cannot recommend. We also have some concern about the lack of a website or customer service center.

If you’re still interested in losing weight, we suggest you find a supplement that is affordable, but that also delivers on its weight-loss claims without the negative side effects. To do this, look for a product that has scientific research and clinical studies that back it up.

Among the best products we’ve seen in 2016 is one called Leptigen. The makers have their own proprietary formula of just four ingredients that have all been shown to help boost weight-loss by promoting fat burning and sparking your metabolism. This supplement does have significant scientific papers and clinical studies proving that it works. There are also many reviews online from satisfied users that have seen great results without unintended side effects.

The makers of Leptigen are so sure that their product will help you lose weight that they’re offering a Special Trial Offer. It’s always encouraging to see a company stand behind their supplement.

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About the Author:

Summer Banks has researched over 5000 products in the past 10 years. 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 Glucomannan Compare?

Previous Glucomannan Review (Updated July 7, 2014):

What You Should Know

Glucomman is a water soluble dietary fiber that is derived from the Konjac root. It is a dietary fiber that helps increase a user's stool bulk by absorbing water. This helps the stool move more easily through the colon. Basically, it is a fiber that expands in the stomach and absorbs fats. The absorbed fats are eliminated from the body and do not undergo digestion, thus nullifying the calorific effect.

List of Ingredients

Glucomannan is a popular ingredient derived from the Konjac Root contained in many products like lipozene and Zeal for Life. It is a natural diuretic found in many diet supplements today. It is also available in tablet form.

Product Features

Glucomannan is often recommended as a solution to obesity. It is also recommended to people who have high cholesterol, and have problems with constipation. Such is the case due to the popularity of Konjac Root, which can be found in meal replacements like Slim Stix. It should never be taken by anyone who has problems with their esophagus as it can lead to choking. It should also never be taken by someone who is diabetic unless under the supervision of their physician as it can alter the person's insulin requirements. Some Diuretics have these adverse effects. Two Glucomanan tablets of 500mg before each meal is often the recommended dose for this product. It should be taken with plenty of water, and again, if not enough water is taken, there is a risk of choking. It is therefore a product that should be ingested with care.

In trials studies, one in twenty obese patients who took capsules of purified Glucomannan sixty minutes before a meal lost 5.5 pounds after eight weeks. It does therefore seem to achieve weight loss in certain people, but there are a number of risks and side effects associated with this product. Glucomannan can be ordered on line as a supplement by itself, at an average cost of approximately $9 for one hundred tablets. Glucomannan is also a common ingredient in a number of weight loss nutritional supplements.


  • It is available for purchase from online pharmacies.
  • It is relatively inexpensive.
  • There are product studies available that indicate Glucomannan can help with weight loss in certain cases.


  • We could not find an official website for Glucomannan.
  • It cannot be taken by anyone who has problems with their esophagus.
  • It can be dangerous for diabetics as it can alter the insulin
  • The sale of Glucomannan has been banned in some countries.
  • Since it is a diuretic, plan on frequently needing access to a bathroom.


There does seem to be some evidence that Glucomannan can result in a small amount of weight loss. However it seems that this supplement would need to be taken on a permanent basis if the effect is to be long-lasting, and this could have negative effects on the user's digestive system. What gives rise to concern, however, are the known side effects of this product which makes us wary of recommending this product as part of your weight loss program. This frenzied popularity is not unique to Glucomannan as other flowering plants also give rise to this same fad adaptation like Senna Tea. A number of warnings have been given by the FDA, regarding safety issues with Glucomannan. We would like to see proper controlled and standardized trials with this product over a very long time period, which assess the long term effects of taking Glucomannan and any risks involved. Until we see these tests, we need to be wary of using Glucomannan on its own and also as an ingredient in other supplements.

Glucomannan Questions & Answers:

We picked apart hundreds of user comments about glucomannan and condensed into this helpful FAQ.

What are the side effects of glucomannan?

Some potential glucomannan side effects include diarrhea, abdominal pain, nausea, bloating and gas.

What are the ingredients in glucomannan?

The glucomannan ingredient is amorphophallus konjac. Different retailers may add more to specific formulas.

Does glucomannan work?

There’s no clinical research proving glucomannan is an effective weight-loss solution. We have found research speaking to the benefits of fiber, but not much more.

Users may want to think hard about mixing it up a little and replacing glucomannan with a supplement like Leptigen, which contains ingredients clinically proven to help you lose weight.

How much does glucomannan cost?

The cost of glucomannan varies, but the average price is about $10. Typically, one bottle will last 30 days.

How should I take glucomannan?

You should take glucomannan according to the directions on the label. Some products recommend taking three capsules per day, one before each meal.

Can I take glucomannan if I have a health condition?

Women who are pregnant or nursing, anyone taking prescription medication, those with health conditions or those under 18 years of age should consult with a licensed physician prior to using dietary supplements, including glucomannan.

What do users like about glucomannan?

Some users liked the affordability of glucomannan and the availability of the supplement.

What do users NOT like about glucomannan?

We found that side effects of glucomannan were a concern and that users didn’t notice weight-loss.

How do I contact the glucomannan customer service department?

You can contact the glucomannan customer service department by visiting the contact us page on the retail site where you purchased the supplement.

How is glucomannan sold?

Glucomannan is sold as a powder and a capsule.

Can glucomannan block airways?

Yes, glucomannan can block airways if not dissolved properly.

Should I drink more water on glucomannan?

Yes, you should drink more water on glucomannan, considering the supplement could be bulk-forming.

Do I need to exercise on glucomannan?

No, you don’t need to exercise on glucomannan, but adding fitness could lead to better results.

Does glucomannan come with a guarantee?

Glucomannan may come with a guarantee, based on where you purchase the supplement. Contact the customer service department for details.

Do you know of any special deals or discounts on glucomannan?

The special deals and discounts on glucomannan depend on the retailer selling the supplement. However, the last several months have been a whirlwind with our readers taking advantage of Leptigen’s Special Trial Offer, which is just the cost of shipping and handling. Click here to give it a try.

27 User Reviews About Glucomannan

Leave comments below
  • 1

    let me ask:”glucomannan extraction from konjac?” thank you!


    Devon (Editor)

    Hi Uyen. Glucomannan and Konjac root are extracted from two different plants.


  • 2



  • 3

    help! I took the capsule apart and took 1 1/2 only, will i choke? Will it expand in my throat? I drank lots of water…it is in Slimquick…i didn’t know how dangerous this substance was…


  • 4

    where can i buy some at?


    Devon (Editor)

    Hi Terri. We’ve listed convenient contact info in the Q&A section.


  • 5

    The comment in the main article regarding the banning of glucomannan in Australia is incorrect. Glucomannan flour food products are approved by FSANZ and are commonly available in shirataki noodles.



    If Glucomannan is banned in Australia, why did recent trials in Australia approve acceptance of a product containing same? Is it banned and why? Have there been any cases of people choking on any product containing G? Why has a person or persons been allowed to ‘buy the rights to G’ in Australia? Terribly confusing and causing people to avoid products they really are safe to use!


  • 6



    Your Name

    go on dr.oz sites


  • 7




    I use bottled water and drink about 2 oz out (to make room at the top to add and shake the glucomannan powder. I put a pack of crystal light (any flavor) into my water and 1/2t of the powder and shake briskly so the powder does not start to gel. Drink the entire bottle right away. Drink 30+ min before a meal and see how much food you CAN’T eat..lol.


  • 8

    Can one take glucomannan along with Alli(orlistat)?


  • 9

    is it working?


  • 10

    Is there any problem using Glucomannan if you are taking Plavix for a heart condition. How does it affect the good bacteria in the intestinal tract?


  • 11

    I just bought it today at Purtains Pride Vitamin Outlet. It was 13.99 a bottle but you get 2 others free. I hope it works. :O)


  • 12
    The Mom

    I’m on a low carb diet and I use this product in powder form, not tablet. I use it just like I would corn starch or unflavored gelatin. I’ve mixed 1/4 tsp with 1 cup of chocolate Calorie Countdown milk and put it in the fridge. An hour later, I’ve got a delicious chocolate pudding that is low carb and high in fiber. I’ve used it as a gravy thickener and it tasted just like gravy made with corn starch. Most stores carry Tofu Shirataki noodles that are a blend of tofu and konjac. They’re great for diabetics and low carb dieters.



    Where do I find this Powder form glucomannan product? GNC does not carry.


  • 13

    Have been using G for about two months from VitaCost(3caps) 2000mg, so far I have found my self more regular and have lost several pounds.( I have also been cutting down on sugar)so can’t say that it is just the G. Here lately I have found myself feeling very bloated which I suppose this means it is working. After reading this article I see the importance of drinking plenty of water, I also will try cutting down on the dosage.


  • 14

    I have been taking an ‘advanced’ form of glucomannan, proplmannan by life extension and i have to say, i like it! I can see where the choking risk comes in to play, when you take it capsule form you really do have to gulp down a lot of water (carefully,but quickly), and at least a 1/2 to a full water bottle. you get the hang of it pretty quickly tho. your supposed to take medication at least 2hrs apart from it. Results wise, within the first couple of days i lost a few pounds, which surprised me considering how much water ive been drinking and how im not actually running to the bathroom. I can see how with exercise this would actually make a really nice supplement. ill keep buying it if the results remain consistent 🙂 . Love it!


  • 15

    I loved using it and lost weight but I also lost hair and muscle mass and became malnourished. I ended up short of breath and wheezing. Major health issues. Not worth it.


  • 16

    how expensive is glucomannan & can it be bought in local stores?



    You can buy glucomannan at GNC for 16.99. Super cheap and its 90 tablets



    Are you or have you used this product, if so have you lost weight with it ?


  • 17
    Frank Rivera

    How does this product inter act if a person is taking medacation for Bi-Polorism and Thyroid meds?



    i take 6 metimucal a day can i take this along with glucomannan?



    I would talk to your doctor. Even herbal supplements can effect medicine.


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