Here's an excerpt from an interview

(CBS) Each year, people spend more than $40 billion on products designed to help them slim down. None of them seem to be working very well. Now along comes hoodia. Never heard of it? Soon it'll be tripping off your tongue, because hoodia is a natural substance that literally takes your appetite away. It's very different from diet stimulants like Ephedra and Phenfen that are now banned because of dangerousside effects.

Hoodia doesn't stimulate at all. Scientists say it fools the brain by making you think you're full, even if you've eaten just a morsel.

Correspondent Lesley Stahl reports.

Hoodia is a bitter-tasting cactus-like plant. 60 Minutes was told that if it wanted to try hoodia, it would have to go to Africa. Why? Because the only place in the world where hoodia grows wild is in the Kalahari Desert of South Africa. Nigel Crawhall, a linguist and interpreter, hired an experienced tracker named Toppies Kruiper, a local aboriginal Bushman, to help find it.

The Bushmen were featured in the movie 'The Gods Must Be Crazy." Kruiper led 60 Minutes crews out into the desert. Stahl asked him if he ate hoodia. "I really like to eat them when the new rains have come," says Kruiper, speaking through the interpreter.

"Then they're really quite delicious." When we located the plant, Kruiper cut off a stalk that looked like a small spiky pickle, and removed the sharp spines. In the interest of science, Stahl ate it. She described the taste as "a little cucumbery in texture, but not bad." So how did it work?

Stahl says she had no after effects – no funny taste in her mouth, no queasy stomach, and no racing heart. She also wasn't hungry all day, even when she would normally have a pang around mealtime. And, she also had no desire to eat or drink the entire day.

"I'd have to say it did work,"says Stahl.