Never in my life did I think a root with cultural significance from Fiji could improve my performance on the golf course.

Under the muted lights of Mai Kai Kava Bar in Gainesville, coconut cups line the countertop. A few customers pull up tall stools to the bar, unpacking their laptops as they order off the menu. Mai Kai ...

Editor's note: While kava is not a controlled substance in the U.S., precautions should always be taken with unregulated substances. Some countries (like Australia) classify kava as a depressant drug.