Hoodia San Bushmen
By Tom Mangold - BBC Two's Correspondent
Imagine this: an organic pill that kills the attacks and appetite obesity. It has no known side effects, and controls a molecule that fools your brain into believing you are full.
Deep inside the African Kalahari desert, grows an ugly cactus named the Hoodia. It thrives in extremely high temperatures, and takes years to grow.
The Hoodia San Bushmen of the Kalahari, one of the world's most former and most primitive tribes, had been eating the Hoodia for thousands of years, to stave off hunger during long search trips.
When South African scientists were routinely testing it, they discovered the plant contained a previously unknown molecule, which has since been baptized P 57.
The license was sold to a Cambridgeshire bio-pharmaceutical company, Phytopharm, who in turn sold the growth and marketing rights to the giant Pfizer Corporation.
Fortune cactus. A molecule in the cactus causes you feel full
When I traveled to the Kalahari, I met families of the San ushmen.
It is a sad, impoverished and moved tribe, still unaware they are sitting on top of a goldmine.
But if the Hoodia works, the 100,000 San strung along the edge of the Kalahari will become overnight millionaires on royalties managed by their South African lawyer Roger Chennells.
And they will need all the help they can to secure the money.
Currently, many bushmen smoke large amounts of marijuana, suffer from alcoholism, and have neither possessions nor any sense of the value of money.
The truth is no-one has fully grasped what the magic particle means for their counterparts in the developed world.
Blood sugarAccording to the British Heart Basis 17% of men and 21% of women are obese, while 46% of men and 32% of women are overweight.
So the drug's marketing potential speaks for itself.
Phytopharm's - Dr. Richard Dixey explained how P.57 actually works:
"There is a part of your brain, the hypothalamus. Within that mid-brain there are nerve cells that feel glucose sugar.
"When you eat, blood sugar goes up because of the food, these cells start burning and now you are full.
What the Hoodia seems to contain is a molecule that is about 10,000 times as active as glucose.
"It goes to the mid-brain and actually makes those nerve cells fire as if you were full. But you have not eaten. Nor do you want to."
Clinical trials - Dixey organized the first animal trials for Hoodia San Bushmen. Rats, a species that will eat literally anything, blocked eating completely.
When the first human clinical trial was guided, a morbidly obese group of people were placed in a phase 1 unit, a place as about prison as it gets.
All the volunteers could do all day was read papers, watch television, and eat.
Half were given Hoodia, half placebo. Fifteen days later, the Hoodia group had reduced their calorie intake by 1000 a day.
It was a stunning success.
The cactus testIn order to see for ourselves, we drove into the desert, four hours north of Capetown in search of the cactus.
Once there, we found an unattractive plant which sprouts about 10 tentacles, and is the size of a long cucumber.
Each tentacle is spanned in spikes which need to be carefully peeled.
The San will finally throw off 1000s of years of oppression, poverty, social isolation and discrimination
Roger Chennells, lawyer
Inside is a slightly unpleasant tasting, fleshy plant.
At around 1800hrs I ate about half a banana size - and later so did my cameraman.
Soon after, we began the four hour drive back to Capetown.
The plant is said to have a feel-good almost aphrodisiac quality, and I have to say, we felt good.
But more significantly, we did not even think about food. Our heads really were telling us we were full. It was a magnificent deception.
Dinner time came and went. We reached our hotel at almost midnight and went to bed without food. And the next day, neither of us wanted nor ate breakfast.
I ate lunch but without appetite and very little pleasure. Partial then full appetite gave slowly after 24 hours.
The futureMr Chennells is ecstatic:
"The San will finally throw off thousands of years of social isolation, oppression, poverty and discrimination.
"We will create trust funds with their Hoodia royalties and the children will join South Africa's middle classes in our lifetime.
"I envisage Hoodia cafes in London and New York, salads will be served and the Hoodia cut like cucumber on to the salad.
"It will need flavoring to counter its bitter taste, but if it has no side effects and no cumulative side-effects."
For more information visit: Hoodia San Bushmen