Self Improvement

Mandy Kloppers

Is Glucomannan good for you?

I’ve recently been trying to lose weight (eating too much because of boredom in lockdown!) and found a supplement online. So far it seems to be helping me as I feel less hungry. I was lying in bed last night wondering about the ingredients because I have liver problems and wondered if the supplement might cause extra strain to my liver. I did some research today and was surprised to find that there are many positive benefits of the main ingredient in the supplement – Glucomannan. If you are trying to lose weight, you might find this info useful…

5 Glucomannan Health Benefits 

1. Weight Loss

Konjac root’s fiber has a very low calorie content but is very high in fiber. Similar to many vegetables, this is a combination that promotes a healthy waist line. Of course, the rest of your diet has to be healthy, and you also need to be exercising regularly. Consuming konjac powder can help weight loss by promoting a feeling of fullness or satiety, which makes you less likely to overeat.

In a 2005 study, 176 healthy overweight people were randomly assigned to ingest either a fiber supplement or a placebo while on a calorie-restricted diet. The fiber supplements were either glucomannan, glucomannan and guar gum, or glucomannan along with guar gum and alginate. All of the subjects consumed a balanced 1,200-calorie diet plus either the fiber supplement or a placebo. After a five-week observation period, the researchers found that all of the fiber supplements plus controlled diet led to a decrease in weight compared to placebo plus diet. However, they conclude that glucomannan specifically produced a reduction in body weight in overweight yet otherwise healthy subjects, but the addition of guar gum and alginate did not seem to cause any additional loss of weight.

Conversely, some studies, like a 2012 one published in the Journal of the American College of Nutrition, did not show that taking glucomannan led to any statistically significant weight loss.  However, it’s safe to say that glucomannan can likely be effective for promoting weight loss when it’s combined with an overall weight-reducing lifestyle, including a healthy diet and regular exercise.

2. Natural Prebiotic

Probiotic foods are certainly essential for gut health and overall well-being, but prebiotics are what actually help “feed” probiotics. Prebiotics — like glucomannan as well as garlic, jicama and artichokes — are types of non-digestible fiber compound. Glucomannan, like all prebiotics, passes through the upper part of the gastrointestinal tract and remains undigested because the human body can’t fully break it down. But once prebiotics reach the colon, where they’re fermented by the gut microflora, they create probiotics.

Konjac root powder is a prebiotic that feeds the friendly bacteria in the intestine. A study published in 2008 demonstrated that glucomannan supplementation increases the fecal concentration of probiotics in general as well as specific probiotics like bifidobacteria and lactobacilli.

Why is this important? Higher intakes of prebiotics are linked to benefits, including:

  • lower risk for cardiovascular disease
  • healthier cholesterol levels
  • better gut health
  • improved digestion
  • lower stress response
  • better hormonal balance
  • higher immune function
  • lower risk for obesity and weight gain
  • lower inflammation and autoimmune reactions

The fact that konjac root is a prebiotic is one of the reasons why it has the next benefit.

3. Constipation Relief

Constipation is a common problem typically caused by a low-fiber diet, dehydration and lack of exercise. Several studies have demonstrated that glucomannan may be helpful for constipation. When consumed, the powder works as a prebiotic in your system, which is very helpful for promoting healthy bowel movements.

Glucomannan is considered a bulk-forming natural laxative, which means that the intake of it is able to promote a larger, bulkier stool that more easily passes through the colon. It also encourages a stool that requires less straining to expel.

A preliminary trial and a number of double-blind trials found glucomannan to be an effective constipation treatment. For constipated individuals, glucomannan and other bulk-forming laxatives typically encourage a bowel movement within 12 to 24 hours of intake. Studies have shown three to four grams to be effective for constipation. (6)

One 2008 study specifically found that a modest dose of a konjac glucomannan supplement encouraged bowel movements in constipated adults by 30 percent and improved colonic ecology in general. (7)

4. Lowers Cholesterol

A systemic analysis of 14 glucomannan studies was published in the American Journal of Clinical Nutrition, and it revealed that the use of glucomannan had significantly beneficial effects on total cholesterol, LDL cholesterol, triglycerides, as well as body weight and fasting blood glucose. However, it did not affect HDL cholesterol or blood pressure.

More specifically, glucomannan was able to do the following in these studies: (8)

  • Lower total cholesterol by 19.3 mg/dL
  • Lower LDL cholesterol by 16 mg/dL
  • Lower triglycerides by 11.1 mg/dL
  • Lower fasting blood sugar by 7.4 mg/dL

How in the world does glucomannan help the body lower these important measures of health? Being the fiber-centric substance it is, it’s able to decrease absorption of cholesterol in the gut by sponging up water in the digestive tract, which reduces the absorption cholesterol by the body. You then have less cholesterol floating around in your blood.

5. Helps Diabetics

There are more than 20 scientific studies involving glucomannan and diabetes. One of the ways it can help diabetics is because it delays the stomach’s natural emptying process, which leads to more gradual sugar absorption and lower blood sugar levels after meals.

A study published in Diabetes Care was small (only 11 hyperlipidemic and hypertensive type 2 diabetics), but it showed very positive effects of konjac fiber. The study subjects, who were being treated conventionally with a low-fat diet and drug therapy, were given biscuits enriched with konjac fiber. Overall, the researchers concluded that the addition of konjac fiber to conventional treatment may improve blood sugar control, blood lipid profile as well as systolic blood pressure in high-risk diabetic patients. In turn, they believe konjac fiber can improve the effectiveness of conventional type 2 diabetes treatment.

Another study gave 72 type II diabetic subjects konjac food for 65 days. Overall, it was concluded that konjac food is very useful in the prevention and treatment of hyperglycemia. ( Hyperglycemia or high blood sugar commonly affects diabetics. It’s a condition in which an excessive amount of glucose (sugar) circulates in the blood.

Overall, taking glucomannan by mouth or including it in your diet may help to reduce cholesterol, blood sugar levels and blood pressure in people with diabetes, which is why it should be part of a healthy diabetic diet plan.



Glucomannan infographic