This conclusive evidence of the health-promoting properties of Rooibos in humans was presented to 150 members of the media, health sector and Rooibos industry at a Rooibos Science Café at the MTN ScienCentre on 26 November 2008.
Researchers traced the protective effect of Rooibos by looking at two important markers in the blood, as well as the oxidative status of the 40 adults who participated in the study. They found a significant decrease in conjugated dienes and malondialdehydes of 35% and 50% respectively – two blood markers that indicate oxidative damage – in the group that drank six cups of Rooibos per day for six weeks.
“This means that Rooibos may help to slow down atherosclerosis, or the hardening of arteries,"" explained Dr Marnewick.
On top of this, Rooibos also increased the levels of the body’s own “super anti-oxidant” called glutathione and helped to reduce the levels of “bad” LDL -cholesterol significantly.
“This is incredible news for Rooibos and the public,” said Mientjie Mouton, a director of the South African Rooibos Council. “We need scientific evidence to substantiate what we have always known – that Rooibos is good for you!”
Dr Marnewick also explained that they asked study participants for feedback on how they felt during the clinical trial. “Many of them reported feeling irritated during the washout period when they could not drink Rooibos, and much calmer once they were enjoying their six cups of Rooibos per day. That is why she will continue the clinical trial to look at the effect of Rooibos and stress.”
At the same Science Café Dr Carl Albrecht, head of Research at the Cancer Association of South Africa (CANSA) gave an overview of nearly a decade of research at South Africa ’s Medical Research Council into the ability of Rooibos to prevent or slow down cancer. He also emphasised the importance of the ability of Rooibos to reduce oxidative stress in the body, as shown by the results of a study on rats, published in 2003.
“I am elated that Dr Marnewick and her team were now able to prove that Rooibos also has this effect in the human body,” he added. Oxidative stress plays a role in the development of a whole range of diseases, including cancer, stroke, heart and liver disease, diabetes and Alzheimer’s.
Another important milestone was the discovery, published in 2004, that Rooibos can prevent and slow down skin cancer in mice.
“The next challenge is to prove that Rooibos can also prevent cancer in people, and I believe that there is a good chance that we’ll be able to prove this,” Dr Albrecht said.
This Rooibos Science Café was organised by the South African Rooibos Council who invests in Rooibos research, along with funding partners such as South Africa ’s National Research Foundation as well as the Medical Research Council and CANSA.
Photograph: (left) Harvested Rooibos leaves (right) Dr Jeanine Marnewick of the CPUT Oxidative Stress Research Centre, Dr Carl Albrecht of the Cancer Association of South Africa
Information courtesy of Southern Science, South Africa Images courtesy of the South African Rooibos Council
