The mysterious low-carb food, demystified.
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If you follow a keto lifestyle or you want to keep your carb count low, you'll probably run across konjac. It's a curious plant used in low-carb food that may need some clarifying. Here, we'll explain what it is, how to cook with it and fill you in on the shirataki noodles made from it.

What is konjac?

Konjac, also known as elephant yam, is a plant commonly grown in Asia. The starch-like corm (kind of like a tulip bulb) of the plant is used to make food like noodles and "rice." It contains glucomannan, which is a water-soluble dietary fiber and is sometimes used as a weight-loss supplement.

How do you cook with konjac?

In powder form, konjac is used to thicken soups and sauces the way you might use cornstarch. However, there are a few brands that use it to make shirataki noodles or shirataki rice which are considered low-carb and keto-friendly. (Trying to eat low-carb? Check out these Healthy Low-Carb Recipes.)

What are shirataki noodles?

Shirataki noodles are gelatinous noodles made from konjac. They're commonly used in Japanese cooking (there is also shirataki rice). You can buy shirataki noodles online or find them in Asian supermarkets. The noodles and rice are marketed as low-carb (or no-carb) ingredients because their carb content is so low, the net carbs for a serving is zero. The theory is that those few carbs are fiber-rich and pass through your body without being absorbed. (Check out more Low-Carb Pastas to Try Instead of Classic Noodles.)

Is konjac good for you?

Its nutritional worth is still being evaluated, but as a dietary supplement, konjac (and glucomannan) is not yet regulated by the Food and Drug Administration. However, in January 2020, the FDA announced its intention to propose glucomannan be added to the definition of dietary fiber that was established in 2016.

The FDA says it made the decision based on scientific evidence that shows it may help lower blood cholesterol levels. Aside from that and the low-carb claims, a study from the Institute of Nutritional Science at Chung Shan Medical University in Taiwan found that konjac improves gut health and prevents constipation, so you may start seeing it a bit more.

What are the side effects of konjac root?

We mentioned that konjac is used as a thickener in cooking—that means it swells when it's mixed with water, which can be dangerous if you're eating it in certain forms. In the early 2000s, the FDA issued several recalls for fruit jelly candies made from konjac because of choking hazards. The problem was that the candies didn't dissolve in your mouth and could get caught in your throat. Other than that, there aren't any known major side effects.

What does konjac taste like?

Like any flavor, the taste of shirataki noodles is liked by some and not liked by others. Some people think konjac and shirataki noodles have a "fishy" taste. For some, that's a deal breaker, but others claim that if you like fish, you may like shirataki noodles and rice.

If you're curious about shirataki noodles but are hesitant to try them, EatingWell's Shrimp Tofu Noodles recipe (pictured below) is a good place to start. The noodles in this recipe are a blend of konjac and tofu, which can mellow the flavor. Also, opting to serve konjac noodles with a flavorful sauce or other ingredients can make the taste less apparent.