Glucomannan – Weight Loss Benefits And Side Effects

Glucomannan weight loss benefits and side effects

What is Glucomannan?


It is a water-soluble all natural dietary fiber.

Sources: It is extracted from the wood of conifers and roots of elephant yam (konjac) and orchids.

Uses: It has many health benefits ranging from treatment of gastrointestinal diseases to usage in dietary supplements like Trimtone, Instant knockout fat burner, etc.

Similar weight loss ingredients: Chitosan, nopal, etc.

It is a dietary fiber which naturally occurs in roots of elephant yams and orchids, as well as conifers. It is water soluble and is known to play an effective role as a weight loss supplement. Glucomannan constitutes 40% of the dry weight of elephant yams and has been commonly used in many traditional cuisines and herbal mixtures in Southeast Asia. In addition to weight loss, it serves many purposes in the food and beverage industry too.

Benefits of Glucomannan for Weight Loss

Glucomannan helps in weight loss through the following mechanisms:

  • Reduces protein and fat absorption
  • Delays gastric emptying
  • Leads to increased levels of satiety
  • Instills a feeling of fullness which reduces food intake
  • It has very few calories
  • It acts as food for the gut-friendly bacteria which might have an effect for reducing body weight
  • Reduces the level of total and LDL cholesterol

How Does It Work?

woman lost a lot of fat around her waist

The gut-friendly bacteria are known to provide protection against fat gain. By acting as a food source for these bacteria, glucomannan reduces fat gain in the body. When glucomannan enters the stomach, it expands by absorbing water which reduces the absorption of fats and carbs. By becoming a spongy bulk in your stomach, it leaves less room for food intake which means you tend to eat fewer calories. This promotes weight loss.

Other Benefits

Following are some other benefits of glucomannan:

  • Used as a food additive
  • Used as a thickener and emulsifier
  • Added to other products such as noodles, pasta and flour
  • Added in drink mixes
  • Used in preparing tofu, noodles, konjac jelly
  • Helps in treatment of constipation and improves the adverse conditions in diabetes
  • Maybe effective for hypertension and hyperthyroidism

Clinical Studies

factors in losing weight

A study ( conducted on 176 healthy but overweight participants investigated the effect of glucomannan on weight loss. The volunteers were either given a placebo or a glucomannan supplement along with proper diet and regular exercise. Three different glucomannan supplements were tested for their effect and according to results; all three supplements were successful in reducing weight of the participants.

In a randomized control study ( performed in 2007, participants were either given a placebo or glucomannan combined with psyllium husk. At the completion of the study after 16 weeks, the group receiving the combo lost 10 pounds as compared to the placebo group who lost an average of 1.7 pounds.

Side Effects

When consumed in food or as capsules or powder, glucomannan is likely safe for most adults. A unique characteristic of glucomannan is its ability to expand by absorbing water. It can absorb as much as 50 times more water than its weight. Due to this characteristic, it is advised to take glucomannan with at least one to two glasses of water to avoid the possibility of blocked esophagus or throat if glucomannan expands before reaching the stomach. Some mild side effects include:

  • Diarrhoea
  • Soft stools
  • Heartburn or flatulence
  • bloating

A word of caution

For people who have diabetes, they must consult with their doctor before starting with glucomannan because it may interfere with the absorption of certain drugs for diabetes. Pregnant and breast-feeding mothers are advised to avoid its use because of lack of research in this area.


Girls working out in gym

Glucomannan is proven to be an effective supplement for weight loss, but like all other supplements, it produces the best results when combined with a calorie restricted diet and proper exercise. Because it is generally safe to use by adults, you can easily incorporate this ingredient to supplement weight loss. Just make sure to consult your doctor before you start on this ingredient so as to avoid any health compromising conditions.

If you are thinking that there is something out there which will help you lose weight without cutting on your calories or proper work out, then you will be disappointed. All supplements are known to speed up the process and supplement your weight loss regime – they are not miracle workers! So keep this fact in mind while starting on any available weight loss supplements.