Shirataki noodles are a unique food that's very filling yet low in calories.
These noodles are high in glucomannan, a type of fiber that has impressive health benefits. In fact, glucomannan has been shown to cause weight loss in numerous studies.
This article explains everything you need to know about shirataki noodles, including their benefits and cooking instructions.
Shirataki noodles are long, white noodles. They are often called miracle noodles or konjac noodles.
They're made from glucomannan, a type of fiber that comes from the root of the konjac plant.
Konjac grows in Japan, China and Southeast Asia. It contains very few digestible carbs — but most of its carbs come from glucomannan fiber.
"Shirataki" is Japanese for "white waterfall," which describes the noodles' translucent appearance. They’re made by mixing glucomannan flour with regular water and a little lime water, which helps the noodles hold their shape.
The mixture is boiled and then shaped into noodles or rice-like pieces.
Shirataki noodles contain a lot of water. In fact, they are about 97% water and 3% glucomannan fiber. They're also very low in calories and contain no digestible carbs.
A variety called tofu shirataki noodles is very similar to traditional shirataki noodles, but with added tofu that provides a few additional calories and a small number of digestible carbs.
Summary Shirataki noodles are a low-calorie food made from glucomannan, a type of fiber found in the Asian konjac plant.
Glucomannan is a highly viscous fiber, which is a type of soluble fiber that can absorb water to form a gel.
In fact, glucomannan can absorb up to 50 times its weight in water, as reflected in shirataki noodles' extremely high water content ().
These noodles move through your digestive system very slowly, which helps you feel full and delays nutrient absorption into your bloodstream ().
In addition, viscous fiber functions as a prebiotic. It nourishes the bacteria living in your colon, also known as the gut flora or microbiota.
In your colon, bacteria ferment fiber into short-chain fatty acids, which can fight inflammation, boost immune function and provide other health benefits (, , ).
A recent human study estimated that fermenting glucomannan to short-chain fatty acids produces one calorie per gram of fiber ().
Since a typical 4-ounce (113-gram) serving of shirataki noodles contains about 1–3 grams of glucomannan, it's essentially a calorie-free, carb-free food.
Summary Glucomannan is a viscous fiber that can hold onto water and slow down digestion. In your colon, it's fermented into short-chain fatty acids that may provide several health benefits.
Shirataki noodles can be a powerful weight loss tool.
Their viscous fiber delays stomach emptying, so you stay full longer and end up eating less (7, ).
In addition, fermenting fiber into short-chain fatty acids can stimulate the release of a gut hormone that increases feelings of fullness ().
What's more, taking glucomannan before consuming a lot of carbs appears to reduce levels of the hunger hormone ghrelin ().
One review of seven studies found that people who took glucomannan for 4–8 weeks lost 3–5.5 pounds (1.4–2.5 kg) ().
In one study, people who took glucomannan alone or with other types of fiber lost significantly more weight on a low-calorie diet, compared to the placebo group ().
In another study, obese people who took glucomannan every day for eight weeks lost 5.5 pounds (2.5 kg) without eating less or changing their exercise habits ().
However, another eight-week study observed no difference in weight loss between overweight and obese people who took glucomannan and those who did not (13).
Since these studies used 2–4 grams of glucomannan in tablet or supplement form taken with water, shirataki noodles would likely have similar effects.
Nevertheless, there are no studies available on shirataki noodles specifically.
Additionally, timing may play a role. Glucomannan supplements are typically taken up to an hour before a meal, while the noodles are part of a meal.
Summary Glucomannan promotes feelings of fullness that may cause a reduction in calorie intake and lead to weight loss.
Glucomannan has been shown to help lower blood sugar levels in people with diabetes and insulin resistance (, , , , ).
Because viscous fiber delays stomach emptying, blood sugar and insulin levels rise more gradually as nutrients are absorbed into your bloodstream ().
In one study, people with type 2 diabetes who took glucomannan for three weeks had a significant reduction in fructosamine, which is a marker of blood sugar levels ().
In another study, people with type 2 diabetes who took a single dose of glucomannan before consuming glucose had significantly lower blood sugar levels two hours later, compared to their blood sugar after a placebo ().
Summary Shirataki noodles can delay stomach emptying, which may help prevent blood sugar spikes after meals.
Several studies also suggest that glucomannan may help lower cholesterol levels (, , , , ).
Researchers note that glucomannan increases the amount of cholesterol excreted in stool so that less is reabsorbed into your bloodstream ().
A review of 14 studies found that glucomannan lowered “bad” LDL cholesterol by an average of 16 mg/dL and triglycerides by an average of 11 mg/dL ().
Summary Studies show that glucomannan may help lower “bad” LDL cholesterol and triglyceride levels.
Many people have chronic constipation or infrequent bowel movements that are difficult to pass.
Glucomannan has proven an effective treatment for constipation in both children and adults (, , , , ).
In one study, severe constipation was successfully treated in 45% of children taking glucomannan, compared to only 13% of the control group ().
Summary Glucomannan may effectively treat constipation in children and adults due to its laxative effects and benefits for gut health.
For some, the glucomannan in shirataki noodles may cause mild digestive issues, such as loose stools, bloating and flatulence ().
However, it should be noted that glucomannan has been found to be safe at all dosages tested in studies.
Nevertheless — as is the case with all fiber — it's best to introduce glucomannan into your diet gradually.
In addition, glucomannan may reduce the absorption of certain medications, including some diabetes drugs. To prevent this, take your medication at least one hour before or four hours after eating shirataki noodles.
Summary Shirataki noodles are safe to consume but may cause digestive issues for some. They may also reduce the absorption of certain medications.
Shirataki noodles can seem a bit daunting to prepare at first.
They're packaged in fishy-smelling liquid, which is actually plain water that has absorbed the odor of the konjac root.
Therefore, it's important to rinse them very well for a few minutes under fresh, running water. This should remove most of the odor.
You should also heat the noodles in a skillet for several minutes with no added fat.
This step removes any excess water and allows the noodles to take on a more noodle-like texture. If too much water remains, they will be mushy.
Here is an easy shirataki noodle recipe containing only a few ingredients:
Shirataki Macaroni and Cheese
For this recipe, it's best to use shorter types of shirataki, such as ziti- or rice-shaped noodles.
- 1 package (7 ounces or 200 grams) of shirataki noodles or shirataki rice.
- Olive oil or butter for greasing the ramekin, a small baking dish.
- 3 ounces (85 grams) of grated cheddar cheese.
- 1 tablespoon of butter.
- 1/2 teaspoon of sea salt.
- Preheat oven to 350°F (175°C).
- Rinse the noodles under running water for at least two minutes.
- Transfer the noodles to a skillet and cook over medium-high heat for 5–10 minutes, stirring occasionally.
- While the noodles are cooking, grease a 2-cup ramekin with olive oil or butter.
- Transfer the cooked noodles to the ramekin, add remaining ingredients and stir well. Bake for 20 minutes, remove from oven and serve.
Shirataki noodles can be used in place of pasta or rice in any dish.
However, they tend to work best in Asian recipes. The noodles have no flavor but will absorb the flavors of sauces and seasonings very well.
If you'd like to give shirataki noodles a try, you can find a wide selection on Amazon.
Summary Shirataki noodles are easy to prepare and can be used in a variety of dishes. They're especially tasty in Asian recipes.