The Guardian investigates the Rath Foundation and the other nutritionists who prey on the vulnerable in South Africa

Chris McGreal investigates Matthias Rath and other charlatans in South Africa in No drugs, just take vitamins: the dangerous advice to cure HIV.

Last week the vitamin campaigner Matthias Rath abandoned a libel suit against the Guardian that had been prompted by articles in which he was accused of endangering thousands of lives by promoting his own pills while denouncing more conventional medicines. Rath focuses his business in eight countries across the world through his website, but it was in South Africa - where he gave them away for free - that his activities generated most concern. Here Chris McGreal investigates the Rath Foundation, and the highly controversial claims of other 'nutritionists' working in the country worst affected by the Aids epidemic, who insist their remedies are the solution to a crisis affecting millions of lives.