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The Konjac plant is native to China and cultivated in warm subtropical, eastern Asia. The plant itself is used in many food products, however, it has little taste and resembles a gelatinous jelly.

It can be added to various foods and even used as a vegan substitute for gelatin. The Konjac fiber has been documented as an aide to weight loss due to its natural water absorption qualities, and people have reported reduced hunger levels after consuming Konjac Glucomannan and products containing Konjac Glucomannan.

The Bottom Line – A plant fiber extract with little taste documented as an aid to weight loss, and hunger suppressor.

Glucomannan Health Benefits

Konjac Glucomannan is not known to have any directly specific health benefits as it is a dietary fiber with little nutritional content. Although Konjac Glucomannan does not have any direct health benefits to the user in terms of nutrients, it has been documented that it may help with weight loss, which, in turn, does have some great health benefits linked to it.

Reduction in weight (of overweight subjects) can reduce cholesterol levels, reduce the risk of heart disease, and reduce the risk of diabetes.

Below is a list of the possible benefits we’ve found:

Konjac Glucomannan Can Help With Weight Loss

There have been several studies documenting the effects of Konjac Glucomannan in people trying to lose weight. The results appear to be relatively mixed due to lack of comprehensive and well-controlled studies, however, initial reports do seem to suggest that supplementing Konjac Glucomannan, in combination with a well-balanced diet, may well lead to weight loss.

One review conducted in 2008 involving fourteen studies showed an overall reduction in body weight, LDL cholesterol, and triglycerides. The review found that on average, each participant experienced approximately 0.79 kg of weight loss over an 8 week period. [1]

However, a subsequent study not included in this review due to it being conducted years later in 2013, found no significant results in terms of weight reduction.

“glucomannan supplements (3.99 g daily) were well tolerated but did not promote weight loss in overweight and moderately obese individuals consuming self-selected diets and maintaining usual physical activity patterns”

This could be due to the participants being allowed to consume a diet of their choice. It appears that Konjac Glucomannan may encourage weight loss when combined with restricted diet, and exercise. [2]

Konjac Glucomannan Can Help Lower Cholesterol

Studies have shown that konjac glucomannan can help to reduce Cholesterol levels. A study conducted by the Department of Clinical Physiology and Occupational Medicine, Orebro Medical Centre Hospital, Sweden investigated 63 healthy Men supplementing Konjac Glucomannan daily at 3.9 g.

They found total cholesterol levels reduced by 10%, and low-density-lipoprotein cholesterol (LDL-C) concentration levels reduced by 7.2%. the same study also showed a reduction in triglycerides by 23% and a reduction in systolic blood pressure by 2.5%. [3]

How To Use Glucomannan

Konjac Glucomannan can be purchased as a pill supplement, and there is a range of Konjac food products available for purchase online and in many supermarkets.

The most common methods of taking Konjac Glucomannan are:

  1. Konjac Food Products
  2. Konjac Root Capsules 

The typical dosage amount for Konjac Glucomannan ranges between 1 – 3 grams daily. It is recommended that you do not exceed 3 grams per day.

Are There Any Foods That Contain Glucomannan?

There are many food products that contain Konjac Glucomannan as an added ingredient, or as the main ingredient. These products are generally made specifically for weight loss and can be purchased from online retailers and health food stores.

Glucomannan Side Effects List

Side effects are generally mild and rarely experienced by the user, however, the list below outlines possible side effects.

  • Bloating
  • Diarrhea or loose stools
  • Abdominal pain
  • Gas
  • Nausea

Note: these side effects are possible but may not be the typical user experience.

Is Glucomannan Safe?

The only time Glucomannan is unsafe to consume is if you have abnormalities of the esophagus or gut. Glucomannan comes with a choking risk and must be taken with adequate water to ensure it reached the stomach.

Despite this, when taken in the recommended dose and not mixed with other medication, this is safe to consume.

Remember, prior to using Konjac Glucomannan, you should consult with your doctor if you have any kind of medical condition.

When Should I Not Take Glucomannan?

  • If you are pregnant and/or breast-feeding: There is not enough research in this area to give a definitive answer. Speak to your local practitioner.
  • If you have abnormalities of the esophagus or gut: Glucomannan may be unsafe for you.
  • If you’re a child under the age of 18: There is not enough research in this area to give a definitive answer. Speak to your local practitioner.

Has Glucomannan Been Linked To Any Deaths?

Konjac Glucomannan has not been linked to any deaths.

The Bottom Line – Considered to be safe to use within recommended dosage with potentially mild side effects but not to be consumed if you are pregnant, breastfeeding or by persons under the age of 18. Must consult a medical professional before taking if you suffer from a pre-existing medical condition or take other medications.

Where Can I Buy Glucomannan & Do I Need A Prescription?

Konjac Glucomannan Extract is readily available to buy without a prescription from all good health stores, online retailers and some supermarkets.


Konjac Glucomannan is a widely available dietary supplement designed at helping to reduce weight, lower blood pressure, and lower cholesterol levels.

While there have been several studies to analyze the effectiveness of Konjac Glucomannan, many of them appear to lack controlled environments leaving the participants to follow any diet they see fit.

This has lead to very mixed results in determining how effective Konjac Glucomannan is for weight loss.

However, it would appear that Konjac Glucomannan does indeed reduce blood pressure and lower cholesterol, however, in order to see significant results regarding weight loss, you should be combining this supplement with a controlled diet, and exercise.

You can either purchase Konjac Glucomannan supplements in pill form, or you can find specific Konjac Glucomannan food products online, and in high street retailers.

Beth Coats, RD LN
Beth Coats, RD LN
Staff Writer

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Fact Checked

This article has been reviewed and fact-checked by a certified nutritionist, and only uses information from credible academic sources.