Down to a tea — how Stellies graduate brought us closer to an indigenous gel to protect against skin cancer

Graduation day. Photo: Facebook

30 Mar 2025

Dr Lana Keet’s research has shown how rooibos and honeybush leaves can be combined to create a highly effective local sunscreen.

The next time you treat yourself to a cup of South Africa’s quintessential indigenous teas, rooibos, and its lesser-known companion, honeybush (heuningbos), and think they are only great as refreshing beverages, pause for a minute. Have another sip. And think again.

There are more uses for these caffeine-free teas than ending up in a cup after they have been harvested, graded and sold.

Dr Lana Keet, a graduate from Stellenbosch University’s 2024 PhD student crop, has shown through diligent research that rooibos and honeybush contain properties that make them ideally suited to be used together as a sunscreen lotion that can protect against skin cancer. If taken to a production level, Keet’s remarkable research could bring less-expensive but highly effective sunscreens within reach of many South Africans for whom the products on the market are too expensive.

Sadly, this economic reality puts many people under the blistering African sun at risk of getting skin cancer. A cheaper and freely available skin protector could make a significant contribution to shielding more people from skin cancer.

Keet is from the village of Kylemore, a settlement in the shadow of the Groot Drakenstein mountains in the Dwarsrivier Valley near the Helshoogte Pass, in the Stellenbosch-Pniel region of the Western Cape. When she was capped in December, her parents William, a retired school principal, and Sheila, a librarian who has been lured out of retirement by Stellenbosch University, and her grandmother Caroline shared her graduation glory with her.

Born in 1985, when a state of emergency was the apartheid government’s response to the ungovernability that was spreading through the townships, Keet is the first born of two daughters in the family.

sunscreen honeybush Honeybush in bloom. (Photo: Wikimedia Commons)

The Keets are an institution in Kylemore. Lana’s uncle Andre is deputy vice-chancellor for engagement and transformation at Nelson Mandela University. His brother Eugene obtained his PhD from the University of the Free State in 2024 with a thesis about fatherhood, and another brother, Neil, is a retired teacher and a composer. Their sister Lorraine is also a retired teacher.

Raised in a family of such high achievers, Keet headed for Stellenbosch University to study medicine after matriculating from Lückhoff High School. Decades before that, in 1969, apartheid laws that wanted to make Stellenbosch white resulted in the teachers, pupils and workers of Lückhoff High on Banhoek Road in the heart of the town being marched to the coloured township of Idas Valley on its outskirts.

They had to physically carry desks, tables and books, as well as memories, to their new school premises. This was a painful, degrading and humiliating experience that is still talked about today.

Keet and her generation represent young people who, although they are not blind to the pain and suffering that forced removals caused in their families, are refusing to be victims forever. In an interview, a confident Keet reflected on her failed attempt to study to become a doctor with a youthful candidness. “I thought I wanted to be a doctor. I soon realised that this profession was not meant for me.”

Because her results were not good enough, Keet could not take her medical studies beyond her first year. She took a hard look at her situation. Some hard truths surfaced.

“Studying medicine was not what I was supposed to be doing. I went into a BSc direction. I could not decide what it was that I should be focusing on and resolved to follow a broad BSc direction that included mathematics and science.”

Subjects such as genetics, biochemistry and physiology appealed to her. “Biochemistry was my absolute favourite subject.”

The Keet siblings are Corné (left) and Lana. (Photo: Supplied)

In 2010, when South Africa hosted the Soccer World Cup, she reported at Stellenbosch to start her honours degree with biochemistry as her chosen field. “It was a difficult year, though it had some fun. Working with researchers did me a world of good.”

Opportunities were not calling out to her after she gained her honours degree. A major change for her came when she received a fully funded bursary, which the Medical Research Council (MRC) had made available for a master’s student to do research into the medicinal properties of first rooibos and later both rooibos and honeybush.

“I was not having any success in getting a job, even though I had an honours degree. Then this opportunity came. I thought, yes, and grabbed it. It was a huge jump to go from doing my honours to the master’s programme,” Keet said.

Another breakthrough in her research direction arrived via an MRC research internship that was part of the council’s early career scientists programme. It allowed her to continue in the direction that she began with her master’s degree.

It was far from a trouble-free journey, however. Her mentor, Professor Wentzel “Blom” Gelderblom, died after he had gone into cardiac arrest. Death caused more disruption in her life when it claimed another influential figure in her development: Dr Sedicka Samodien, who died of Covid-19.

“Some major hurdles came my way. I was resolute that I wouldn’t abandon my studies, and here I am,” Keet said.

Dr Lana Keet. (Photo: Dennis Cruywagen)

Graduation day. (Photo: Facebook)

A resolute determination kept her eyes fixed on the groundbreaking work in which she was engaged. During her master’s research, she developed a cell model to determine the incubation time and level of tea concentrate that were required to produce a cream that would not be harmful and cause skin damage.

The Agricultural Research Council, the MRC and the Rooibos Council wanted the medicinal qualities researched and marketed if possible. The goal was to develop a gel that could be applied to the skin as a sunscreen. Keet’s pioneering research has proved that producing such a product is indeed possible.

Would what she has proved in the laboratory make a huge commercial impact? “We still have a long way to go before we will be able to manufacture a gel,” Keet said.

“What I did was basic science. I’ve opened the door to a process that could lead to the production of a sunscreen from our very own indigenous plants. The next step is to do biopsies and persuade a sample group of people to join the research programme.”

Although excited by the possibility of adding to the medicinal arsenal to combat skin cancer, Keet has her feet firmly on the ground. “Further research must be done on how to use rooibos and heuningbos together in one product,” she said.

“The ratio must be worked out carefully so that we don’t get side-effects. As a tea, rooibos is refreshing. However, if used as a salve in high dosages, it can cause inflammation and free radicals. That’s why trials are necessary to arrive at the perfect balance between rooibos and heuningbos.”

Keet has done the groundbreaking research. The next step is the development of a rooibos and heuningbos product that will be available over the counter as a homegrown protector against the sun. DM

This story first appeared in our weekly Daily Maverick 168 newspaper, which is available countrywide for R35.

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