Konjac root is likely safe for healthy adults. Konjac root may interfere with blood sugar control, so diabetics who are taking konjac root should exercise caution, according to WebMD. Individuals who aren't used to high-fiber intake may experience discomfort and gas, states the University of Michigan Health System.
Konjac root contains a water-soluble fiber called glucomannan, which is considered a bulk-forming laxative. It is an effective treatment for constipation and may also be used as a treatment for high cholesterol, reports the University of Michigan Health System. Consumption of glucomannan may also affect the absorption of drugs that are taken orally, according to WebMD.