The konjac plant, also known as the konnyaku potato, is used to make konnyaku and other low-calorie health foods in Japan. These foods are often gelatinous or rubbery. In addition to containing very few calories, konnyaku is 97 percent water and 3 percent glucomannan (a dietary fiber that aids in digestion and passes through the body largely undigested).
Like many "superfoods," konjac is seen by some marketers as a potential weight-loss miracle worker. Two popular diet pills, Lipozene and Centrilene, make use of konjac root. Essentially, these medications are just high-fiber pills. If taken properly, they can aid in digestion and have somewhat of a laxative effect. But they're hardly unique. Konjac pills have been around for a long time under many different names.
If not taken with a proper amount of water, konjac products can be a choking hazard. In late 2001, the Food and Drug Administration (FDA) moved to block the import of konjac candy. These gelatinous candies became lodged in the throats of some children, causing them to choke to death. Because of their lumpy form, the candies mold to the shape of the throat and are difficult to dislodge. In 2002, many companies recalled their konjac candies.
Products containing a type of fiber called psyllium husk seed can also cause a choking hazard. Like other types of fiber, psyllium husk seed absorbs water. If cereal containing psyllium husk seed becomes lodged in the throat, it can expand and cause choking. For this reason, products containing psyllium husk seed shouldn't be consumed dry, and children and people with difficulty swallowing should be careful. The FDA recommends that you check product labels for information about choking hazards.
In the end, it's best to approach diet pills of all sorts with skepticism. Expanding diet pills, hydrogel-based, konjac-derived or otherwise, do about as much as drinking more water, eating less and loading up on fiber through natural foods. The Harvard School of Public Health recommends that adults get 20 to 35 grams of fiber per day. A healthy diet of fruits, vegetables, whole grains and nuts should provide you with more than enough fiber. It may help you lose weight, lower your cholesterol, and you'll be lowering your risk of several diseases at the same time.
For more information about dieting, diet pills, and related topics, please check out the links in the next section.