Does Glucomannan Diet Really Work? A Detailed Review

Does the glucomannan diet supplement work? Is it better than the rest?

There is always a lot of interest and curiosity to use natural weight loss supplements like this one we are discussing now.

In the past years, some of the popular prescription pills meant for losing weight were proved to be very harmful with long-term side effects on health.

Most of us prefer natural supplement because it is safe for our health.

One of the best natural slimming pills that have a lot of good reputation today is the Glucomannan.

It is more than four years since this supplement was first made known to the weight loss community by Dr.Oz. He claimed this supplement as “one of the best ways to control your hunger.”

Dr.Oz also called glucomannan “nature’s skinny sponge” that can suppress the appetite and make you lose weight in a way that is never experienced by anyone before.

We cannot take all tall claims that Dr.Oz makes on his TV show as 100% true and infallible.

Here, in this glucomannan review article, we are going to examine carefully, the science and truth behind this natural weight management solution.  Does Glucomannan work for shedding extra pounds? Read this article to find more details on this diet supplement.

What is Glucomannan?

Glucomannan is an extract from the roots of elephant foot yam in the form of water-soluble dietary fiber. It is a soluble, fermentable, and highly viscous dietary fiber.

The binomial name of this plant is Amorphophallus paeoniifolius. It is also popularly known as a white-spot giant arum.  Konjac is another subspecies of Amorphophallus, which is very popular in Japan for making dietary noodles and pasta.

The elephant foot yam is a tropical tuber crop grown primarily in the Indian subcontinent, Africa, and East Asia. This elephant foot yam is very popularly used in making various kinds of vegetable cousins, and so it is grown as a cash crop in most of these countries.

The glucomannan extract has very significant medicinal value as a prominent ingredient in several Indian herbal remedies.

It comes in powder, tablet, and capsule forms as a natural remedy for Type 2 diabetes, lowering LDL cholesterol, asthma, abdominal pain, emesis, dysentery, enlargement of spleen, piles, elephantiasis, diseases due to vitiated blood, rheumatic swellings, etc.

The elephant foot yam has a long history of varied uses in food preparations as vegetable cousins, powder for preparing pasta, flour for making noodles, etc.

In recent times, glucomannan gained a lot of attention as a weight loss supplement.

The best quality of this weight loss supplement is got from the elephant foot yam grown in the Indian subcontinent.

Glucomannan has nearly 40% weight of the actual dry yam powder.

It is also used as a food additive, specifically as a thickener and emulsifier.

It is an excellent dietary fiber as it has an unusual ability to absorb water in large quantities.

A single glucomannan capsule weighing about 1 gram can absorb an entire glass of water and make it into a thick gel-like sponge. It is this unique quality of this supplement that helps in weight loss.glucomannan capsule and diet

How Is Glucomannan Used?

Glucomannan as powder or capsules could be safely used as an appetite suppressor and fats absorber.

There are three different ways one can use this supplement. Let us have a brief look at each of them.

Glucomannan Powder: It is pleasant and practically tasteless. The powder is usually mixed into other food or smoothies. Usually, the powder when used with water it adds a good bit of thick consistency and bulk to the food.

Glucomannan In Processed Food: I am sure you might have already heard about the ‘miracle noodles,’ the Japanese shirataki noodles, the most popular food that comes with glucomannan mixed into it.  You will also find some chewing gums and candies with this ingredient blended into them.

Glucomannan Capsules/Tablets: It is the most convenient and commonly used method, especially as a weight loss supplement.

For best results about 1 gram of this supplement, the tablet should be used along with 8 ounces of water about 30 minutes before the meal.

In the intestine, the powder that is contained in the capsule gets diluted with water, and it would then expand to form a bulky fiber sponge in the stomach.

The powder “sponges” up the water in the digestive tract and absorbs the carbohydrate and fat that will be expelled from your body through a natural route later on. This has a direct effect on weight loss, as your body will not get a chance to absorb more than the required amount of glucose and fat.

As this dietary supplement occupies a lot of space in the stomach, you began to sense a feeling of fullness and satiation even before you start eating. In this way, it suppresses the appetite by filling up the stomach with a gel-like fibrous content.

Glucomannan Effect On Weight Loss

The Glucomannan powder will absorb a lot of water to become sponge-like fibrous bulk. It is a good natural treatment for constipation used in the Indian system of Ayurvedic Medicines for centuries.

But the recent studies conducted on the supplement showed that the bulky fibrous formation of Glucomannan helps in weight loss in several ways.

First of all, this supplement like a sponge will absorb not only the water but also a good amount of glucose, fructose, and fat before they are being exported into the bloodstream.

This has a direct impact on reducing sugar and LDL cholesterol levels in the blood.

It swells up like a spongy fiber and will occupy the space in the stomach meant for the food we eat. This fibrous formation will make us feel full and prevent us from eating more food.

This spongy fiber also remains in the stomach for a longer time, and we would not feel hungry for a longer time.

This supplement is a soluble fiber that acts as a block on intestinal walls from absorbing protein and fat.

It also nourishes and feeds the friendly bacteria in the intestine that then turn into fatty acids like butyrate to prevent fat storage in the belly.

There are studies’ results that suggest one of the possible reasons for weight gain is the inactivity or non-existence of friendly gut bacteria. If that is the case, this diet supplement has more reason to be an excellent weight loss supplement.

Glucomannan has all the beneficial effects of all other soluble fibers, but it is better than all of them because it is more viscous.

Does Glucomannan Really Work?


It is easy to say a lot of good things about the possible weight loss effects of this natural diet supplement.

But we are more interested in the actual weight loss results of this diet supplement in real situations.

Let us look at some of the authentic studies conducted on this supplement.

In one of the randomized controlled trials (a gold standard in clinical trials) on glucomannan, 176 overweight people were chosen and randomized into four groups. Out of the four groups, 3 were assigned to different dosages of glucomannan supplement, and the 4th group was on placebo pills….all of them were given the same calorie-restricted diet.

After five weeks of the trial period, the glucomannan diet groups showed a significantly greater amount of weight loss results with variation in particular dosages to which they belonged.

In another study conducted in 2007 that was published in the British Journal of Nutrition, the trial study participants taking a glucomannan and psyllium husk combination supplement lost about 10 pounds in 16 weeks compared to 1.7 pounds lost in the placebo group.

Another study that used only glucomannan indicated weight loss results up to 5.5 pounds in eight weeks trial period. This result was achieved without making any changes in lifestyle and a normal diet.

Almost every study conducted on this diet supplement has acknowledged its weight-loss effectiveness.

Glucomannan will work for modest weight loss as it is one of the best soluble fibers. If this is regularly ingested before the meals, it will suppress the appetite and help in reducing the absorption of protein, glucose, and fat by the body.

The preliminary studies’ results and the feedback from actual users are promising. However, the FDA has neither approved any glucomannan products nor accepted the weight loss result claims put forward by several research studies. Here are the final verdicts of 3 major glucomannan studies:


Glucomannan is effective in reducing weight and can produce very satisfactory results when used in combinations with restricted diets and regular physical workouts.

Other Health Benefits

It is a water-soluble fiber. For this reason, in the Indian Ayurvedic Herbal medicines, glucomannan is traditionally used as a natural remedy to overcome constipation and indigestion issues.

As we had discussed at the beginning of this article, this diet supplement can absorb a lot of glucose and fat in the digestive tract itself and leaves a lesser amount of them for the body to absorb.

As this diet supplement is highly viscous, it is like a sponge that sucks even the excess cholesterol in the gut.

For these reasons, it is useful for reducing cholesterol and blood sugar levels in the blood. This also has a direct impact on controlling heart diseases and Type II Diabetes.

Glucomannan is an ingredient in several medicines. For example, glucomannan plus methimazole and propranolol reduce thyroid hormone levels in people who suffer from excess thyroid hormone production.

Glucomannan Side Effects

This is a natural extract from elephant foot yam that has no harsh chemicals, strange drugs, or additives that can cause any serious side effect on health.

As we already know, people in Indian subcontinents are using elephant foot yam as a vegetable. So we cannot expect any side effects in the pure extract from this yam.

In the initial stages, as your digestive system and stomach are getting used to this supplement, some of you may experience mild side effects like bloating, flatulence, soft stools, or diarrhea. The rich soluble fiber in it will naturally make the stools softer than usual.

People under regular medication may find this diet supplement unsuitable for them as this supplement may slightly block the complete absorption of the medicine.

Make sure NOT to consume more than the suggested quantity of diet supplements.

You have to drink at least 8 ounces of water immediately after you consume a glucomannan capsule. Or else this can sometimes cause blockages of the throat or intestine.

Like every other diet supplement, this one too is not recommended for pregnant women and breastfeeding mothers.

If you have problems with low blood sugar, this supplement should be consumed with strict monitoring of your blood sugar level. Glucomannan usually reduces the blood sugar level.

Dosage And Where to Buy It

The typical Glucomannan capsule is of 1 gram content. The best dosage for all ordinarily healthy people is 1 gram of glucomannan to be taken 30 minutes before the meals with two glasses of water.

It is highly viscous, and it can absorb a lot of water; 50 times more than its weight.  Therefore, high dosages can cause unwanted troubles for you.

The best weight loss result from this diet supplement is possible only when it is taken about 30 minutes before the meals.

You can buy glucomannan from any reliable online sellers who are known to sell the best quality of products.

The Bottom Line

As I surfed through several of the Glucomannan reviews, I could see that almost every one of them is very positive about the good weight loss results from this fibrous diet supplement.

The many studies that have already been conducted on this diet pill also have shown proven results with it.

Besides the weight loss results, this pill also has several other health benefits. You can get rid of constipation and diarrhea issues with it. This is also useful for Type II diabetes and cholesterol control.

Glucomannan diet supplement will certainly give modest weight loss results; it will be very effective if it is used in combination with a controlled diet and physical workouts.