"Rooibos is good for you", is a contention that’s been around for at least the past 40 years, but increasingly scientific research indicates that there’s more than a little substance to the claim.
The first evidence of people making tea with rooibos only occurs about 300 years ago. Wild plants were harvested using axes and the leaves were bruised with hammers before being left to ferment in heaps and then dried in the sun. It’s essentially the same process used today, although now the equipment is a little more sophisticated.
Rooibos became popular with the early Dutch settlers, not for its health but economic advantages. It was a cheap alternative to the expensive black tea that was imported from Europe.
Carl Thunberg, a botanist from Europe, was the first to document the rooibos plant and the tea brewed from it in 1772. After this, the scientific community doesn’t appear to have lavished much attention on the "mountain" tea until the early 20thcentury.
That’s when Dr Le Frans Nortier, a doctor and nature lover, began researching rooibos’ medicinal value and agricultural potential.
Rooibos of course is not a true tea, but a herb and the brew made from the dried leaves is a herbal infusion known as a tisane. The vibrant amber hue comes from the natural colourants that develop during the post-harvest fermentation or oxidation process and is brought about by natural enzymes in the plant.
Green or unfermented rooibos is a lighter colour, with a milder taste. Both traditional and green rooibos are natural products and contain no colourants, additives or preservatives – although they can be stored for long periods without the taste or quality deteriorating. They have no kilojoules and contain no caffeine.
Scientific interest in rooibos remained muted until after 1968, when Mrs Annetjie Theron used rooibos to help soothe her allergic baby’s colic. She published a book called Allergies: An Amazing Discovery and went on to launch a range of health and skin-care products with rooibos as the main ingredient.
Although Mrs Theron’s evidence was anecdotal rather than scientific, there’s little doubt that her claims stirred interest in rooibos’ health benefits. Since then there’s been considerable research done in South Africa and abroad into how rooibos might help prevent or treat a variety of illnesses.
Rooibos contains a complex and unique blend of antioxidants, the most abundant of which - aspalathin - is found only in the plant species Aspalathus linearis. Antioxidants bind with free radicals, preventing them from damaging cells and causing cancer or oxidising with cholesterol to clog blood vessels resulting in heart attacks and strokes.
Research over the past decade has proven the therapeutic ability of rooibos to help prevent cancer, protect the liver against disease, boost the immune system, relieve allergies and treat digestive disorders.
By investing in research in South Africa and keeping a close eye on studies done overseas, the South African Rooibos Council is able to provide scientific evidence to confirm the plant’s health benefits as well as police inaccurate or unsubstantiated claims on behalf of the industry.
Its research budget is R1 million a year and it is currently supporting studies at several local universities and science councils on how rooibos can prevent cancer and oxidative stress as well as the link between rooibos and exercise. A project on rooibos and obesity has been approved for funding in 2011.
Scientists here and around the world continue to research rooibos to gain a better understanding of this unique herbal tea. Some are investigating the health benefits of rooibos and its potential to combat a range of diseases, while others are trying to understand how the bioactive components in rooibos work.
Recent and ongoing research
- International researchers found the compounds in rooibos are potent enough to measurably elevate the antioxidant levels in blood, boosting the body’s natural defences. The effect peaks an hour after drinking two cups of rooibos.
“That’s why we recommend drinking up to six cups of rooibos spaced throughout the day for a sustained health benefit,” says Professor Jeanine Marnewick from the Cape Peninsula University of Technology, who led a local study that showed the beneficial effect of drinking rooibos to promote heart health.
The benefits are the same whether the rooibos is drunk hot, as tea, or cold as iced tea. Six cups also provide the recommended daily hydration.
- South African scientists from the Medical Research Council’s PROMEC Unit and the Oxidative Stress Research Centre at the Cape Peninsula University of Technology have found that rooibos could help prevent skin cancer.
The implications are particularly relevant in South Africa which, with 20 000 reported cases annually and 700 deaths, has the second highest incidence of the disease in the world after Australia.
The CPUT study concluded that the polyphenolic-rich extracts from rooibos and honeybush have anti-tumour and photoprotective properties. This indicates potential for use in cosmeceuticals for sun protection and as part of a strategy for preventing non-melanoma skin cancers in humans.
The MRC team found that rooibos exacerbated cell death in UV exposed cells, which could play a role in cancer prevention. It also concluded that rooibos may prevent skin cancer by delaying the progression of abnormal cells, interfering with their growth and viability.
- Researchers in Pakistan, Canada and Germany joined forces to explore the use of rooibos to treat gastrointestinal upsets, using an animal model. Their results explained the biochemistry of how the flavonoids and other active compounds in rooibos achieve a calming effect on the digestive system. They concluded that it is justified to use rooibos for the treatment of gastrointestinal disorders such as gut spasms.
- Two South African researchers, Professor Elizabeth Joubert and Dr Johan Louw, are co-applicants of a worldwide patent (filed in 2007) to develop and produce an anti-diabetic extract of rooibos, particularly for the treatment of Type 2 diabetes.
- A Japanese study showed that rooibos could reduce inflammation in rats with colitis (open sores in the colon) via increased antioxidant activity and a consequent reduction in damage to DNA caused by oxidation.
- Researchers in Japan showed that the active compounds in a water-soluble fraction of rooibos restored immune function in immune-suppressed rats. These results hold significant potential for future research into the immune-boosting properties of rooibos that might benefit people living with HIV/Aids.
- Researchers from the Slovak Republic have demonstrated the anti-ageing effect of rooibos in Japanese quails. The birds were given rooibos to drink and had ground rooibos added to their food. The hens on the rooibos diet laid more eggs and kept laying eggs as they were getting older, compared to the control group.