Prof Jeanine Marnewick

For leading a team that promotes rooibos tea, to be included in a personal daily regime as a health promoting option, supported by science.

25 February 2021


The 2019/2020 NSTF-South32 for Communication Award was won by Prof Jeanine Marnewick , Research Chair: Biotechnology and Director: Applied Microbial and Health Biotechnology Institute, Cape Peninsula University of Technology received this Award for leading a team that promotes rooibos tea, to be included in a personal daily regime as a health promoting option, supported by science. For Professor Marnewick, the glaring absence of scientifically-supported evidence around health claims made about rooibos herbal tea and the misuse and misinterpretation of existing scientific outcomes set her course into the world of this popular beverage. She made it her goal to find out the health properties and science behind this leaf and to then disseminate true facts and information to those who enjoy its flavour and its health benefits


For Professor Jeanine Marnewick, the glaring absence of scientifically-supported evidence around health claims made about rooibos herbal tea and the misuse and misinterpretation of existing scientific outcomes set her course into the world of this popular beverage. Her goal? To find out the health properties and science behind this leaf and to then disseminate true facts and information to those who enjoy its flavour and its health benefits.

“Rooibos is a proudly South African product that is easily available and has a strong following, both locally and internationally,” explains Marnewick. “Informing the public of research outcomes is critical to empowering them to make informed decisions when it comes to the plethora of teas and herbal teas available on the shelves. I wanted to scientifically substantiate the anecdotal evidence available on rooibos and share these outcomes with the public and relevant industries.”

It turned out that rooibos does have a scientific leg to stand on. The studies undertaken by Marnewick and her colleagues revealed that adults at risk of developing heart disease — who consumed six cups of rooibos daily for six weeks — showed improved good cholesterol levels.

Another study found that rooibos can have an impact on the enzyme that causes high blood pressure.

As a result of this research and a growing body of scientific evidence behind rooibos, numerous organisations have endorsed its health properties. These include the Cancer Association of South Africa and the South African National Halaal Authority.

“The concepts of antioxidants, polyphenols, and oxidative stress were fairly unfamiliar when I started my research communication activities. Since then public knowledge has increased,” adds Marnewick. “The effectiveness of communication can be seen in the increase in reach — the number of invitations for talks and interviews and the different sectors requiring assistance in advising them on how rooibos should be used or incorporated into their respective industries.”

The science that substantiates the anecdotal evidence around rooibos and health is still in its infancy. By focusing research on relevant diseases in communities, the ongoing goal of Marnewick and her team is to provide people with a complementary approach to prevent or delay the onset of debilitating health conditions.

For two decades, Marnewick has paid attention to rooibos. It’s made a difference to how rooibos is perceived and the benefits it provides. We look forward to more discoveries on the potent abilities of this humble herbal tea.

To read the full Mail & Guardian supplement of articles about the work of all the 2020 Award Winners, click here.