Rooibos herb and tea information  (Aspalathus linearis) by Ray Sahelian, M.D.
February 13 2016

Rooibos tea originates from the leaves and stems of the indigenous South African plant Aspalathus linearis. Rooibos tea is also known as Red-Bush and grows on high mountain ranges. This plant has gained much attention for clinical purposes in the case of nervous tension, allergies, dermatitis, and various digestive problems. Recently, antioxidant activity has also been attributed to the tea on the basis of its flavonoid content.
   As of 2015, I could not find few published studies in humans regarding the benefits or side effects of rooibos tea or supplements.

Constituents of Rooibos herb and its active ingredients
Rooibos contains different bioactive phenolic compounds such as dihydrochalcones, flavonols, flavanones, flavones, and flavanols. The main flavonoids in rooibos are dihydrochalcone aspalthin, rutin, quercetin, luteolin, nothofagin, and orientin. Another flavonoid is rooibos herb is chrysoeriol (luteolin 3'-methyl ether). This flavonoid is known for antioxidant, antiinflammatory, antitumor, antimicrobial, and antiviral properties.

What does the research say about Rooibos herb?
Rooibos tea is a powerful antioxidant, has anti-HIV activity, may protect brain cells from damage by toxins, and additionally has anti-tumor potential. Rooibos tea administration prevents age-related accumulation of lipid peroxides in several regions of rat brain.
   My thoughts: I have rooibos tea on my kitchen counter, along with a dozen or so different teas, and I drink a cup once in a while.

J Ethnopharmacol. 2008. South African herbal teas: Aspalathus linearis, Cyclopia spp. and Athrixia phylicoides--a review. Rooibos (Aspalathus linearis (Brum.f) Dahlg.) and honeybush (Cyclopia Vent. species) are popular indigenous South African herbal teas enjoyed for their taste and aroma. Traditional medicinal uses of rooibos in South Africa include alleviation of infantile colic, allergies, asthma and dermatological problems, while a decoction of honeybush was used as a restorative and as an expectorant in chronic catarrh and pulmonary tuberculosis. Traditional medicinal uses of Athrixia phylicoides DC., or bush tea, another indigenous South African plant with very limited localised use as herbal tea, include treatment of boils, acne, infected wounds and infected throats. Currently rooibos and honeybush are produced for the herbal tea market, while bush tea has potential for commercialisation.

J Ethnopharmacol. 2011. Effects of rooibos (Aspalathus linearis) on oxidative stress and biochemical parameters in adults at risk for cardiovascular disease. In South Africa, the plant Aspalathus linearis is traditionally used as a "tea" referred to as rooibos or redbush. This plant has been listed as a medicinal plant based mostly on anecdotal evidence. Confirming its popular use, consumption of fermented, traditional rooibos significantly improved the lipid profile as well as redox status, both relevant to heart disease, in adults at risk for developing cardiovascular disease.

Fermented and unfermented rooibos tea
What is the difference between fermented (red) and unfermented (green) forms of rooibos tea.
   Rooibos tea leaves can be quickly dried after picking to prevent oxidation and this is called green rooibos. When rooibos tea leaves are fermented, they turn an orange red color. The unfermented green rooibos tea has a higher antioxidant level. Fermented rooibos tea has a sweeter taste.

Rooibos for skin applied topically
I am working on an article for a natural health magazine and luckily just came across your website and some information that you had on rooibos. Basically, this article is covering global skin care and for South Africa, I am featuring rooibos. Would you be able to tell me how rooibos can help skin when applied topically?
   Limited studies in rodents indicate that certain compounds in rooibos herb are able to cross through the skin and help with tumor prevention. I have not seen studies in humans regarding the benefit of rooibos herb ingredients in terms of skin care or to prevent or treat wrinkles.

Inhibition of tumour promotion in mouse skin by extracts of rooibos (Aspalathus linearis) and honeybush (Cyclopia intermedia), unique South African herbal teas.
Cancer Lett. 2005. Marnewick J, Joubert E, Joseph S, Swanevelder S, Swart P, Gelderblom W. PROMEC Unit, Medical Research Council, Tygerberg, South Africa.
The modulating effect of ethanol/acetone (E/A) soluble fractions, prepared from methanolic extracts of processed and unprocessed rooibos (Aspalathus linearis) and honeybush (Cyclopia intermedia) as well as green (Camellia sinensis) teas was established in a two-stage mouse skin carcinogenesis assay. Topical application of the tea fractions prior to the tumour promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA), on ICR mouse skin initiated with 7,12-dimethylbenz[a]anthracene (DMBA) suppressed skin tumorigenesis significantly with the green tea E/A fraction exhibiting a 100% inhibition, unprocessed honeybush 90%, processed honeybush 84%, processed rooibos 75% and unprocessed rooibos 60%. The green tea fraction, with the highest flavanol/proanthocyanidin content, also exhibited the highest protective activity (99%) against hepatic microsomal lipid peroxidation, and completely inhibited skin tumour formation.

Transport of aspalathin, a Rooibos tea flavonoid, across the skin and intestinal epithelium.
Phytother Res. 2008. Huang M, du Plessis J, du Preez J, Hamman J, Viljoen A. University of the Witwatersrand, Department of Pharmacy and Pharmacology Johannesburg, South Africa.
 This study investigated the in vitro transport of aspalathin, a unique flavonoid constituent of Rooibos tea, across intestinal epithelial cells and the human skin. The transport studies were conducted for both pure aspalathin solutions and extracts from unfermented (or green) Rooibos (Aspalathus linearis) aerial plant material across human abdominal skin in vertical Franz diffusion cells and Caco-2 cell monolayers in Transwell 6-well plates. Only 0.01% of the initial aspalathin dose from both the test solution and extract permeated through the skin. A portion of 0.07% of the initial aspalathin dose penetrated the different layers of the skin for the green Rooibos extract solution and 0.08% for the pure aspalathin solution. The transport of aspalathin across Caco-2 cell monolayers was concentration dependent and reached almost 100% of the initial dose in the highest concentration tested for the extract, while it was only 79%of the initial dose for the highest concentration of the aspalathin solution.

Topical rooibos for hair growth
There are claims that rooibos constituents, when applied topically, lead to hair growth. Cosmetochem international claims to have done a rooibos hair study back in 1998, but a search on Pubmed in 2008 using the keywords rooibos hair does not lead to any published studies.

Aspalathin information
What is the specific benefit of aspalathin from rooibos tea? Why is it aspalathin better or stronger than other antioxidants?  Also, does green rooibos have a higher concentration of aspalathin and greater anti-aging potential?
   There are countless antioxidants in fruits, vegetables, herbs and various plants. Each antioxidant works in a slightly different way in the body. It is not practical to claim aspalathin is better than EGCG in green tea or vitamin E, or astaxanthin, etc. Just as it is preferable to eat a variety of fruits and vegetables, it is a good idea to consume a number of different antioxidants. I am not aware of any actual studies done with aspalathin supplements. Limited evidence suggest green rooibos has a higher antioxidant profile than red, but for practical purposes it should not make too much difference.

Rooibos Tea research studies
Modulation of hepatic drug metabolizing enzymes and oxidative status by rooibos (Aspalathus linearis) and Honeybush (Cyclopia intermedia), green and black (Camellia sinensis) teas in rats.
J Agric Food Chem. 2003.
Rooibos and honeybush teas significantly enhanced the activity of cytosolic glutathione S-transferase alpha. A significant to marginal increase in the activity of the microsomal UDP-glucuronosyl transferase was obtained with unprocessed rooibos and honeybush teas, respectively. Oxidized glutathione (GSSG) levels were significantly reduced in the liver of all tea treated rats while reduced glutathione (GSH) was markedly increased in the liver of the herbal tea treated rats. These changes resulted in a significant increase in the GSH/GSSG ratio by the unprocessed, processed rooibos and unprocessed honeybush teas. Green and black teas markedly to significantly decreased the oxygen radical absorbance capacity in liver homogenates, respectively. Modulation of phase II drug metabolizing enzymes and oxidative status in the liver may be important events in the protection against adverse effects related to mutagenesis and oxidative damage.

Unfermented rooibos tea: quantitative characterization of flavonoids by HPLC-UV and determination of the total antioxidant activity.
J Agric Food Chem. 2003.
Unfermented rooibos originates from the leaves and the stems of the indigenous South African plant, Aspalathus linearis, and it has been reported to have a higher content of flavonoids compared to that of fermented rooibos. Main compounds determined were aspalathin, isoorientin, orientin, and rutin, followed in order by isovitexin, vitexin, isoquercitrin and hyperoside, quercetin, luteolin and chrysoeryol.

Hepatoprotective effect of rooibos tea (Aspalathus linearis) on CCl4-induced liver damage in rats.
Physiol Res. 2003.
Hepatoprotective properties of rooibos tea (Aspalathus linearis) were investigated in a rat model of liver injury induced by carbon tetrachloride (CCl(4)). Rooibos tea, like N-acetyl-L-cysteine which was used for the comparison, showed histological regression of steatosis and cirrhosis in the liver tissue with a significant inhibition of the increase of liver tissue concentrations of malondialdehyde, triacylglycerols and cholesterol. Simultaneously, rooibos tea significantly suppressed mainly the increase in plasma activities of aminotransferases (ALT, AST), alkaline phosphatase and billirubin concentrations, which are considered as markers of liver functional state. The antifibrotic effect in the experimental model of hepatic cirrhosis of rats suggests the use of rooibos tea as a plant hepatoprotector in the diet of patients with hepatopathies.

Effects of rooibos tea extract on antigen-specific antibody production and cytokine generation in vitro and in vivo.
Biosci Biotechnol Biochem. 2001.
Rooibos tea contains a large amount of flavonoids and acts as a potent antioxidant. In this study, we examined the effects of Rooibos tea extract on antigen-specific antibody production and cytokine generation in vitro and in vivo. Our findings suggested that Rooibos tea extract may facilitate the antigen-specific antibody production through selective augmentation of IL-2 generation both in vitro and in vivo. Collectively, Rooibos tea intake may be of value in prophylaxis of the diseases involving a severe defect in Th1 immune response such as cancer, allergy, AIDS, and other infections.

Anti-human immunodeficiency virus activity of oligosaccharides from rooibos tea (Aspalathus linearis) extracts in vitro.
Leukemia. 1997.
The active substances, acid polysaccharides, were extracted with 1% sodium hydroxide from the leaves of rooibos tea (Aspalathus linearis), Du Zhong Cha (Eucommia ulmoides Oliv.) and Japanese tea leaves (Camellia sinensis). The alkaline extracts of Rooibos tea and Du-Zhong tea leaves, but not Japanese tea leaves suppressed the HIV-induced cytopathicity using HIV (HTLV-III) infected MT-4 cells. From these results, it is probable that acid polysaccharides from rooibos tea were extremely safe, and that HIV infection may be suppressed by daily intake of the alkaline extracts of rooibos tea and Du-Zhong tea.

The suppression of age-related accumulation of lipid peroxides in rat brain by administration of Rooibos tea (Aspalathus linearis).
Neurosci Lett. 1995.
The protective effects of Rooibos tea, Aspalathus linearis, against damage to the central nervous system (CNS) accompanying aging were examined by both the thiobarbituric acid reaction (TBA) and magnetic resonance imaging (MRI) methods in brains of chronically Rooibos tea-treated rats. Ad libitum administration of Rooibos tea was begun with 3-month-old Wistar female rats and continued for 21 months. The contents of TBA reactive substances (TBARS) in the frontal cortex, occipital cortex, hippocampus and cerebellum in 24-month-old rats after administration with water were significantly higher than those in young rats (5 weeks old). However, no significant increase of TBARS was observed in Rooibos tea-administered aged rats. When MR images of the brains of 24-month-old rats with and without Rooibos tea as well as 5-week-old rats were taken, a decrease of the signal intensity was observed in the cerebral cortex, hippocampus and cerebellum in MR images of aged rats without Rooibos tea, whereas little change of the signal intensity was observed in MR images of the same regions of 24-month-old rats treated with Rooibos tea, whose images were similar to those of young rats. These observations suggested that (1) the age-related accumulation of lipid peroxides in the brain was closely related to the morphological changes observed by MRI, and (2) chronic Rooibos tea-administration prevented age-related accumulation of lipid peroxides in several regions of rat brain. Whether drinking rooibos tea regularly enhances longevity in humans is not known.

Brief History of Rooibos plant
Rooibos has been drank as a traditional beverage in South Africa by the indigenous peoples for millennia. The name rooibos means red bush, a word given by the Dutch Afrikaaners to the plant, whose leaves turn a reddish color upon drying and fermentation. Rooibos tea has been marketed in the United States since at least the early 1960s when Worthington Foods introduced a beverage named Kaffree containing the rooibos plant.

Johannesburg, 2006- A South African woman, who claims to be the world's oldest living person at 132, advocates fresh food and exercise as the keys to longevity. Moloko Temo holds an identity card from the South African government confirming her birth on July 4, 1874, but international authorities have not verified her age and The Guinness Book of Records gives the title of oldest person to a French woman who died aged 122 and 164 days in 1997. For Moloko Temo, breakfast consists of warm, fresh baked bread, sometimes with a pat of margarine, and herbal rooibus tea. Lunch and dinner is a vegetarian meal of maize, a starchy thin porridge, drenched in fresh milk. She also recommends as a side dish morogo, a leafy African vegetable high in protein and vitamins. Her advise to staying healthy is to "eat (natural foods) and exercise every day."

Q. I enjoy reading the newsletter by Ray Sahelian, M.D. and was particularly interested in the discussion on teas. You didn't mention a tea that I have been told about - it's called rooibos tea red bush and it is supposed to have multiple healing properties when taken regularly. The tea is from Africa and is supposed to have "x" (25, 50) times the amount of antioxidents that green tea has. If the benefits are really there, it would be nice to spread the word. Conversely, if the claims are false, we might be better off trying something else and save our money. Thanks.
   A. We will update this page on rooibos as more research is published.

Q. I am trying to get the truth on receiving the health benifits from rooibos tea. I have been told by a wholesaler that is necessary to boil the tea for it to produce it's health benifits. Do you know if this is true?
   A. I don't know for sure what kind of difference boiling makes, but the longer a leaf or tea is brewed, the more of the ingredients in the herb are seeped into the water. In many cases hot water facilitates the seeping of the chemicals in an herb into the water.

Q. I write for a health magazine and we are doing a roundup of workout energy drinks and we mentioned a product called ReddRox. The ReddRox product includes an ingredient called rooibos and we’d like to get an expert’s take on it. Can you please confirm that rooibos can increase your stamina if you drink it before a workout?
   A. Rooibos is a plant popular in tea form. A June 2009 Medline search did not reveal any human studies that have evaluated rooibos tea in terms of athletic performance or endurance. At this time there is no reason to suspect rooibos tea would have a stamina boost superior to that of other teas.

Does rooibos provide electrolytes and minerals, such as sodium, potassium and magnesium, all which you lose through sweat.
   I find it difficult to accept this claim. Rooibos is a tea that can provide antioxidants and is a healthy addition to one's tea consumption, but it is premature to make fantastic claims about this tea. There are countless herbs and teas that have health benefits.