**KONJAC: Benefits, Side Effects, Uses, Dosage, Warnings?** The konjac or konjac Amorphophalus , is a vegetable that comes straight from the South-East. It grows in forests in Vietnam, China, Indonesia, South Korea and Japan, so it's no surprise that we see that it is the main consumers of konjac. Although ... are generally eaten as an appetite suppressant . They take about 1/2 hour before meals, the effect lining limits the hungry, and are fat absorption during the meal.