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Konjac- aka “Konnyaku”

I like saying the word Konnyaku way better. It is fun to say–”Konnyaku” Pronounced ‘kon·nya·ku’ –  go ahead, say it!     

You said it didn’t you?

Konnyaku is a perennial plant that belongs to the Araceae family. It was introduced to Japan from China and has been used as part of their healthy diet for over 1,500 years.

The main component of Konjac is Glucomannan pronounced ‘glookoman’an‘ , now that is hard to say. Does not roll off the tongue very easily at all.

It is a calorie-free fiber which is very elastic. It is rich in vitamins (A, B1, B2, B6, B12, C, D, and E) protein, lipids, fatty acids, and minerals such as zinc, copper, iron, and magnesium.

Not only is it a healthy food but its gentle texture and ability to hold water make it an excellent skincare product. I am not sure how to make skincare products from this supplement but that will be another post for another time.

So, let’s start with the health benefits of Konjac.


A 2018 study showed the combination of Konjac and American Ginseng over 12 weeks had a moderate and meaningful reduction in HbA1c and lipid concentrations in patients with type 2 diabetes.

Another study looked at 72 subjects over 65 days that were given Konjac food and saw a significant reduction in fasting and postprandial blood sugar and in triglyceride levels of subjects with hypertriglyceridemia.


The American Journal of Clinical Nutrition performed 14 studies showing the use of glucomannan significantly lowered total cholesterol, LDL, and triglycerides. The studies also indicated a decrease in body weight and fasting blood glucose.

Gut Health

Konjac glucomannan (KGM) supplementation increases the good bacteria and decreases the bad bacteria like e.coli and c.dif.(Clostridium perfringens and Escherichia coli) according to these studies. Read more about why gut health is important and what you can do to improve it.


Another study cited by The American Journal of Clinical Nutrition concluded that a modest dose of konjac glucomannan (KGM) supplement promoted bowel function by 30% and improved bowel ecology in constipated adults.


Significant improvement in acne was seen in 26 females between the age of 18 and 39 with active acne lesions in a study using topical application of konjac glucomannan 5% solution.

Wound Healing

Yes, this study was only performed on mice but does show faster wound healing in the mice that were provided supplementation of the glucomannan.

It is not just used internally for wounds but also as a wound dressing. There are increased studies using glucomannan in dressing applications that are showing promising results.

Weight loss

When consumed, glucomannan absorbs a large amount of water in the digestive tract. This reduces the ability of carbs and cholesterol to be absorbed thus supporting weight loss.

It also makes you feel full so you are not as likely to overeat.

167 overweight men and women were given Glucomannan along with a reduction in calories and their weight loss was significant compared to the group that dieted without the use of Glucomannan. Read here for the study details.

Consider combining this with turmeric/curcumin. Learn how turmeric may be able to increase your metabolism and aid in weight loss.

Of course, decreasing overall calories, eating a clean and healthy diet along with exercise are the main components of weight loss. 

Ways to use Konjak

Powder form:

Add ½ tsp of glucomannan powder to your favorite food or drink three times a day15 – 30 minutes before each meal. Glucomannan powder also mixes well in certain foods like oatmeal, yogurt, and sauces — as well as almost every type of beverage.

Still, the best way is at least 15 minutes before the meal to decrease alterations in your blood sugar and aid in the ability to produce the feeling of satiety.


These Shirataki or Wonder Noodles are made from Konjac root. I love them. Not all grocery stores carry them so you may have to order them online. If you have an Asian store you should be able to find them there. I order mine from Thrive Market because they have the best prices and selection.

They come in different styles- Angel hair, fettucini, spaghetti.

They have an elastic chewy texture similar to rice noodles and when you first open the bag the smell will hit you in the face like a big stinky fish!

Once you rinse them they lose the bad smell. You can then add your sauce or broth or whatever topping floats your boat.

I frequently add them to my eggshell bone broth with a little miso. Bam! Healthy ramen noodles.

Oh did I mention they have ZERO calories and less than 1 grams of carbs per serving?

Let me repeat that.  ZERO calories and LESS THAN 1 GRAM of CARBS!!!

Shazam. Now that is what I am talking about and they make me feel full?

Oh, yes please..Miracle Rice:

Same idea as the noodles but 15 calories and only 4 grams of carbs per serving.

It is very important to make sure you drink at least 8 ounces of water with your glucomannan no matter which forms you are consuming to prevent any blockages.

I order my noodles and rice through Thrive as they have the best prices and selection and they arrive in just a few days. I love Thrive Market!

Just like everything, there are side effects and warnings.

The biggest danger lies with the gummy candies made from glucomannan, the tablets, and capsules. 

Due to Konjac’s ability to hold a large amount of water, when in these forms it can swell and cause intestinal or esophageal blockages.

I would stay away from the capsules and tablets and stick to the powdered form that can be mixed into smoothies. I just mix into a glass of water. It is tasteless and dissolves quickly and easily. 

Side effects and warnings

  • bloating
  • diarrhea or loose stools
  • abdominal pain
  • gas
  • Nausea
  • choking

You should always consult with your doctor before starting any new supplement. Especially if you have diabetes as glucomannan can lower your blood sugar levels. Also if you have any intestine or esophageal abnormalities or diseases.

Once you have consulted with your doctor and you are good to go I encourage you to try this non-synthetic plant-based product. You can order from Amazon, iHerb, or from your local health food store. 





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