The scientists conducted a comprehensive study on the links between nutrition and treatment and found that no food has been identified as an effective alternative to appropriate medication in fighting HIV/AIDS and TB.
The South African government currently stresses that nutrition as well as drugs is important in the fight against these devastating diseases despite the fact that the country's health minister has earned herself international ridicule and the nickname "Dr Beetroot" for her views.
Dr. Tshabalala-Msimang has been criticised in the past for stressing the benefits of beetroot, garlic and potatoes in fighting HIV and under-playing the role of anti-retroviral (ARVs) drugs.
South Africa has one of the world's highest HIV infection rates and the country's researchers say that scientific evidence about conditions in South Africa was urgently needed.
The report by the country's top scientific advisory panel concludes that though nutrition is important for general health, is not sufficient to contain either the HIV/AIDS or the TB epidemic and says a well-fed population on its own will not resist HIV/AIDS without anti-retroviral (ARV) drugs.
A more comprehensive approach on the part of the government now means about 280,000 people were on ARV treatment at the end of March this year but that falls well below the estimated 800,000 who are thought to need ARVs in South Africa.
South Africa has one of the world's highest HIV infection rates with an estimated 12% of the country's 47-million population infected with the deadly virus.
South Africa's healthcare system struggles to cope because of a lack of doctors and nurses, many of whom have left the country for better pay abroad; the fight against AIDS has also been confused and hampered by the conflicting messages sent by senior government officials such as Health Minister Manto Tshabalala-Msimang.
Deputy health minister Nozizwe Madlala-Routledge was sacked this month for insubordination, provoking an outcry from AIDS activists who strongly backed her policies and critics who say she was fired for political reasons.
The researchers tested gill tissue from crabs harvested in six different years from the Chesapeake Bay and the gulf coast of Florida. Specimens from each region produced similar results, confirming that the presence of AEP in males and absence in females is the norm for blue crabs.
But, Kleps said, it was still not possible to rule out that the difference between the sexes was due to a difference in their diet. Fortunately, while writing the first draft of the paper, Kleps happened to read that a rare gynandromorphic blue crab -- one half male, one half female -- had been captured by Romuald Lipcius of the Virginia Institute of Marine Science at the College of William & Mary.
The rare gynandromorph is divided down the middle, with a characteristic blue male claw and a female red claw. The underside of the crab is also visibly divided into male and female halves. After the crab died, Lipcius sent Kleps gill tissue from each side for analysis. The measured levels of AEP from the male and female gills provided additional evidence that AEP is a sex-specific compound.
"Since both sides of this strange crab have, of necessity, shared a diet and environment, we had completely independent confirmation of the sex-specific nature of this metabolite," said Kleps.
"That blue crabs have this sex-specific compound may be a fluke, or it might represent a common but overlooked process in animal development," he said.
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