Rooibos Uses, Benefits & Dosage - Drugs.com Herbal Database

Skip to main content
Print
Save

# Rooibos

Scientific Name(s): Aspalathus linearis (Burm. f.) R. Dahlgr.
Common Name(s): Red bush tea, Rooibos tea, Rooibosch

Medically reviewed by Drugs.com. Last updated on Nov 1, 2022.

## Clinical Overview

### Use

Limited clinical studies exist to recommend red bush tea for any indication. Due to the plant's potential for improving oxidative stress, it may have a role in diabetes and cardiovascular disease.

### Dosing

Clinical trial data are lacking to support specific dosing recommendations.

### Contraindications

Contraindications have not been identified.

### Pregnancy/Lactation

Avoid use. Information regarding safety and efficacy in pregnancy and lactation is lacking.

### Interactions

None well documented.

### Adverse Reactions

Information regarding potential adverse effects is lacking. A study of human volunteers drinking 6 cups of rooibos tea daily for 6 weeks noted increases in serum levels of creatinine and in ALT and AST enzymes.

### Toxicology

Long-term, high-dose use may impair kidney and liver function, but few case reports exist.

## Scientific Family

- Fabaceae (bean)

## Botany

Rooibos ("red bush") grows as a low shrub, reaching a height of 1.2 to 1.5 m. It has long, needle-like leaves and small yellow flowers. The plant is native to South Africa and is cultivated extensively for its commercial value as a substitute for common tea. The leaves and twigs are collected, washed, bruised, fermented, dried, cut, and packaged for use as tea. During this process, the leaves change from green to brick red due to the release of a red pigment found in the leaves and stems.(Watt 1962) Synonyms are Borbonia pinifolia Marloth or Aspalathus contaminata (Thunb.) Druce.

## History

"Bush teas" are common throughout Africa and are frequently used as substitutes for common tea. Red bush tea has been popular in South Africa for decades, and commercial preparations are sometimes found in Europe and the United States. In 1994, an American company registered the name "Rooibos" with the United States Patent and Trademark Office. However, the American Herbal Products Association, as well as a South African exporter of the herb and The Republic of Tea company, successfully petitioned to defeat the trademark in 2005, returning the name to the public domain.(AHPA 2005) In 2013, the South African Department of Trade and Industry issued geographic indicator trade restrictions on the name "rooibos" in that country.(DTIRSA 2013)

The tea's lack of caffeine and tannin make it popular as a fragrant and bittersweet, nonstimulating beverage. It has also traditionally been used to treat asthma, colic, eczema, headache, nausea, and mild depression.(DTIRSA 2013, Gouws 2014, Joubert 2013, Watt 1962)

## Chemistry

Chemical constituents detailed for red bush tea primarily consist of flavonoids (ie, catechin, quercetin, rutin, vitexin, dihydrochalcones aspalathin, nothofagin) and phenolic acids (ie, caffeic, p-coumaric, ferulic, vanillic).(de Beer 2015, Duke 2002, Gouws 2014, Krafczyk 2008, Ku 2015) Aspalathin, a dihydrochalcone C-glucoside, was identified in 1965,(Joubert 2005) with green (unfermented) rooibos possibly containing more aspalathin than the commercial fermented rooibos tea.(Han 2014) An enolic phenylpyruvic acid glucoside has also been identified.(Kamakura 2014)

Phenolic content of extracts varies according to season and production methods.(Muller 2013)

Red bush tea contains no caffeine or pyrrolizidine alkaloids and low amounts of tannins (less than 5%), as determined by both spectrophotometry and gas chromatography.(Joubert 2012) The tea contains a relatively high level of vitamin C, as well as some sodium, potassium, magnesium, calcium, and zinc.(Duke 2002, Gouws 2014)

## Uses and Pharmacology

### Anti-inflammatory effects

#### Animal and in vitro data

Anti-inflammatory effects of rooibos and of the constituents aspalathin and nothofagin have been studied in models of colitis and vascular inflammation. Suppression of tumor necrosis factor alpha and interleukin has also been demonstrated.(Ajuwon 2013, Kwak 2015, Muller 2012)

Blood taken from 9 atopic adults was used to test the effects of fermented and unfermented rooibos extracts. Both extracts reduced basophil activation in response to allergen exposure, with the fermented extract having a slightly stronger inhibitory effect.(Pedretti 2020)

Bronchodilator and antispasmodic effects have been demonstrated in mice, possibly via potassium channel modulation.(Lee 2015)

### Antioxidant effects

#### Animal and in vitro data

Antioxidant activity has been demonstrated in laboratory experiments and in cellular systems, and has been studied in vivo in rodents and quail.(Ajuwon 2013, Ajuwon 2014, Awoniyi 2012, Ayeleso 2014, Canda 2014, Chen 2013, de Beer 2015, Dludla 2014, Fukasawa 2009, Hong 2014, Joubert 2012, Jurani 2008, McGaw 2007, Pantsi 2011, Simpson 2013) Reported total antioxidant activity varies depending on the assay method and on fermentation and processing methods.(Ulicná 2008) In Wistar rats exposed to nicotine, rooibos demonstrated reduced oxidative stress and vascular injury.(Smit-Van Schalkwyk 2020)

The unique composition of phytochemicals and combination of metabolic activators, adaptogens, and antioxidants make rooibos an attractive yet underappreciated intervention for FB1 toxicoses.(Sheik Abdul 2020) However, despite studies purporting hepatoprotection via antioxidant activity from rooibos tea, one study showed that aspalathin‐rich rooibos extract did not modulate atorvastatin‐induced hepatotoxic effects in a cell model.(Millar 2020)

#### Clinical data

In a small, acute intervention, crossover study in healthy volunteers (N=15), plasma antioxidant capacity increased significantly with both unfermented and fermented rooibos teas.(Villaño 2010) In another small study among healthy human volunteers, a single serving of rooibos tea did not produce any change in total antioxidant capacity according to the oxygen radical absorbance capacity assay,(McKay 2007) while another study found small increases.(Breiter 2011) Consumption of 6 cups (approximately 1,400 mL) of rooibos tea daily for 6 weeks improved both antioxidant status and lipid profiles among adults with risk markers for cardiovascular disease (N=40).(Marnewick 2011)

### Antiviral activity

#### COVID-19

The clinical features and pathology of acute respiratory disorder induced by SARS-CoV-2 suggest that excessive inflammation, oxidative stress, and dysregulation of the renin angiotensin system are likely contributors to the COVID-19 disease. Rooibos can potentially play a supportive role by modulating the risk of some of the comorbidities associated with COVID-19 in order to promote general health during infections.(Sheik Abdul 2021)

#### Influenza

#### In vitro data

An aqueous extract of rooibos was noted to have activity against both influenza A and B, reducing the ability of the virus to adsorb to host cells.(Idriss 2021)

### Bone effects

#### In vitro data

Polyphenols in red and green rooibos increased osteoblast activity and bone mineralization in in vitro studies.(McAlpine 2021) Additionally, in murine macrophages, osteoclast activity was reduced via inhibition of nuclear factor kappa B activity, with fermented rooibos having a slightly greater effect than unfermented.(Moosa 2018)

### Cancer

#### Animal and in vitro data

Suppression of mutagenic activity has been demonstrated in rodents, including studies of liver and skin tumorigenesis,(Marnewick 2005, Marnewick 2011, Marnewick 2009, Ulicná 2008, van der Merwe 2006) with rooibos tea lowering activity to a greater extent than green tea in at least 1 study.(Marnewick 2011) In prostate cancer cells resistant to enzalutamide, treatment with green rooibos extract reduced proliferation and survival via several mechanisms.(Wang 2022) Interference with Akt signaling was determined to be a mechanism of action for a green rooibos extract rich in aspalathin, which inhibited proliferation of prostate cancer cells resistant to castration.(Huang 2019)

### Cardiovascular effects

#### Animal and in data

In hyperlipidemic mice, aqueous rooibos extract reduced serum cholesterol, triglyceride, and free fatty acid concentrations and decreased adipocyte size and number.(Snijman 2007) An in vitro study demonstrated inhibition of adipogenesis following treatment with hot water–soluble solids from fermented rooibos.(Beltran-Debon 2011) Anticoagulant activity has been described for aspalathin and nothofagin in human umbilical endothelial cells and in mice.(Sanderson 2014) These 2 chemical constituents have also shown activity in inhibiting various mechanisms involved in vascular inflammation.(Duke 2002, Ku 2015, Kwak 2015) In mice, hypotensive effects were demonstrated, possibly via potassium channel modulation.(Lee 2015) In rats fed a high-calorie diet, green rooibos extract lowered heart rate and protected heart tissue from ischemic and reperfusion injury. Improvements were also observed for insulin dependence.(Smit 2022) In isolated perfused rat heart, aqueous rooibos extracts showed cardioprotective properties via inhibition of apoptosis.(Pantsi 2011) In a study using human serum, rooibos acted as an angiotensin-converting enzyme (ACE) inhibitor in a manner similar to that of enalaprilat.(Khan 2006)

#### Clinical data

Following daily consumption of 6 cups (approximately 1,400 mL) of rooibos tea for 6 weeks, improved antioxidant status and lipid profiles (decreased low-density lipoprotein and triacylglycerol, increased high-density lipoprotein) were reported in adults with risk markers for cardiovascular disease (N=40).(Marnewick 2011)

### CNS effects

#### Animal data

Long-term fermented rooibos herbal tea intake affects exploration and anxiety-related behavior in rats, as well as exerts biochemical outcomes in the brain that support the neuroprotective impact of rooibos tea.(Pyrzanowska 2021b)

### Diabetes

#### Animal and in vitro/in vivo data

Experiments in rodents using aspalathin-enriched green rooibos extract,(Mazibuko 2013, Persson 2012) aspalathin,(Han 2014) and enolic phenylpyruvic acid glucoside(Kamakura 2014) suggest that rooibos may have antidiabetic effects, with suppressed increases in fasting blood glucose levels demonstrated. Increased glucose uptake and insulin secretion, as well as reduced insulin resistance, are possible mechanisms of action. Findings were supported by a systematic review and meta-analysis of evidence, in which it was concluded that blood glucose levels were significantly lower in diabetic rodent models treated with a phenolic compound rich in rooibos extracts.(Sasaki 2018)

Another review concluded that rooibos tea has potent antidiabetic properties based on in vitro, in vivo, and various epidemiological studies that suggest consumption of rooibos tea reduces the risk of type 2 diabetes mellitus and its complications. However, the molecular mechanisms of how this herbal tea and its bioactive components impact the major end points of type 2 diabetes mellitus are inconclusive.(Ajuwon 2018) Biotransformation in the gut is most likely responsible for enhancing therapeutic effects observed for the C-glycosyl parent compounds, including aspalathin; these compounds and their derivatives have the potential to regulate multiple factors associated with the development and progression of type 2 diabetes.(Muller 2022)

#### Clinical data

According to a review, various human studies suggest that consumption of rooibos tea reduces risk of type 2 diabetes mellitus and associated complications.(Ajuwon 2018) In a small, placebo-controlled, crossover study examining effects of several botanical extracts on postprandial glucose levels in prediabetic patients (N=19), clinically significant effects of rooibos were limited to the "less healthy" subgroup of patients. Those whose glucose and insulin parameters were closer to "normal" experienced minimal effects, not statistically different from placebo.(Lim 2021)

### Hepatoprotective effects

#### Animal data

In a rat model of nonalcoholic fatty liver disease, the livers of rats given rooibos tea in addition to a high-fat diet had significantly fewer lesions at study end.(Azubuike 2020)

### Metabolic syndrome

According to a systematic review of preclinical studies, rooibos has shown promise in improving metabolic function, in part by reducing markers of oxidative stress and inflammation. Effects were attributed to rutin, a flavonol derivative of quercetin found in several medicinal plants and food sources that have displayed therapeutic benefits against diverse metabolic diseases.(Muvhulawa 2022) Another review highlighted the potential of rooibos extract and aspalathin, a C-glucoside dihydrochalcone, as well as the phenolic precursor Z-2-(beta-D-glucopyranosyloxy)-3-phenylpropenoic acid to prevent metabolic syndrome.(Muller 2018)

#### In vitro data

Effects of rooibos, aspalathin, and nothofagin on steroid hormone biosynthesis have been investigated in H295R cells.(Baba 2009, Schloms 2012)

Aspalathin inhibited xanthine oxidase activity in vitro and reduced plasma uric acid levels in hyperuricemic mice.(Kondo 2013)

#### Clinical data

In an analysis of plasma steroid levels in human plasma following rooibos consumption, increased cortisone plasma levels in males and reduced cortisol to cortisone ratios in both males and females were observed.(Schloms 2014)

## Dosing

Clinical trial data are lacking to support specific dosing recommendations. One small study reported use of 6 cups (approximately 1,400 mL) of rooibos tea per day for 6 weeks to evaluate effects on oxidative stress and biochemical parameters in adults at risk for developing cardiovascular disease.(Marnewick 2011, Schloms 2014)

## Pregnancy / Lactation

Avoid use. Information regarding safety and efficacy in pregnancy and lactation is lacking. Phytoestrogenic effects have been suggested.(Juráni 2008, Opuwari 2015, Shimamura 2006, Stalmach 2009) Rooibos tea has been shown to interfere with steroidogenesis in vivo,(Juráni 2008) possibly due to antioxidant properties, and to improve sperm motility in rats.(Ajuwon 2014, Shimamura 2006) Interference with the acrosome reaction, required for the penetration of sperm to fertilize an egg, has been suggested.(Opuwari 2014) A limited number of in vitro studies suggest an influence of rooibos on basic ovarian cell functions, as well as its potential applicability in female reproductive processes and preventing the effects of environmental contaminants on ovarian functions.(Sirotkin 2021)

## Interactions

No effect on iron absorption has been reported.(Ulicná 2008)

A study on the interaction of rooibos with cimetidine was inconclusive.(Opuwari 2014) Due to the impact on CYP-450, there is a possible risk of herb-drug interactions affecting bioavailability of some coadministered medications. Caution should be exercised.(Pyrzanowska 2021a)

In a study in mice, coadministration of rooibos with atorvastatin resulted in 5.8- and 5.9-fold increases in atorvastatin Cmax and AUC. Altered expression of genes related to metabolism of both cholesterol and fatty acids were also noted.(Patel 2019)

## Adverse Reactions

Information regarding adverse effects is lacking.(Ulicná 2008) Rooibos consumption appears safe in terms of hepatotoxicity; however, there may be a designated group of consumers with higher risk of liver irritation. The contamination of plant material may contribute to herb-induced liver injury.(Pyrzanowska 2021a)

Although microbial contaminants (including Salmonella) may be present due to the fermentation process used to derive the tea product, few reports of contamination exist.(Joubert 2013, Tarirai 2012)

Animal studies have shown increased creatinine levels, but no changes in kidney tissue histology.(Shimamura 2006) A study of human volunteers receiving 6 cups (approximately 1,400 mL) of tea daily for 6 weeks showed increases in serum levels of creatinine, as well as in ALT and AST enzymes.(Marnewick 2011) A case of hepatotoxicity has been reported in a 37-year-old man who consumed 10 cups (2,400 mL) per day of red bush tea for more than a year. He was scheduled for an emergency appendectomy in which his preoperative work-up revealed elevated liver enzymes and thrombocytopenia. All other causes for the hepatotoxicity were ruled out, and the tea was deemed to be the responsible agent.(Reddy 2016)

A risk assessment of the heavy metals in rooibos tea consumed in South Africa concluded that the target risk quotient and the hazard index levels in all analyzed tea samples were well below 1, implying that intake of rooibos tea containing the analyzed heavy metals should not cause a threat to human health. On the other hand, due to high concentrations of trace metals such as chromium, continuous intake may pose a serious chronic health risk due to accumulation in body tissues over time.(Areo 2021)

## Toxicology

Long-term, high-dose use may impair liver and kidney function, but few case reports exist.(Joubert 2012, Shimamura 2006, Swanepoel 1987, Villaño 2010)

## Index Terms

- Aspalathus contaminata (Thunb.) Druce
- Borbonia pinifolia Marloth

## References

## Disclaimer

This information relates to an herbal, vitamin, mineral or other dietary supplement. This product has not been reviewed by the FDA to determine whether it is safe or effective and is not subject to the quality standards and safety information collection standards that are applicable to most prescription drugs. This information should not be used to decide whether or not to take this product. This information does not endorse this product as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this product. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this product. This information is not specific medical advice and does not replace information you receive from your health care provider. You should talk with your health care provider for complete information about the risks and benefits of using this product.

This product may adversely interact with certain health and medical conditions, other prescription and over-the-counter drugs, foods, or other dietary supplements. This product may be unsafe when used before surgery or other medical procedures. It is important to fully inform your doctor about the herbal, vitamins, mineral or any other supplements you are taking before any kind of surgery or medical procedure. With the exception of certain products that are generally recognized as safe in normal quantities, including use of folic acid and prenatal vitamins during pregnancy, this product has not been sufficiently studied to determine whether it is safe to use during pregnancy or nursing or by persons younger than 2 years of age.

Ajuwon OR, Ayeleso AO, Adefolaju GA. The potential of South African herbal tisanes, rooibos and honeybush in the management of type 2 diabetes mellitus. Molecules. 2018;23(3207):1-25. doi:10.3390/molecules23123207
Ajuwon OR, Katengua-Thamahane E, Van Rooyen J, Oguntibeju OO, Marnewick JL. Protective effects of rooibos (Aspalathus linearis) and/or red palm oil (Elaeis guineensis) supplementation on tert-butyl hydroperoxide-induced oxidative hepatotoxicity in Wistar rats. Evid Based Complement Alternat Med. 2013;2013:984273. doi:10.1155/2013/98427323690869
Ajuwon OR, Oguntibeju OO, Marnewick JL. Amelioration of lipopolysaccharide-induced liver injury by aqueous rooibos (Aspalathus linearis) extract via inhibition of pro-inflammatory cytokines and oxidative stress. BMC Complement Altern Med. 2014;14:392. doi:10.1186/1472-6882-14-39225312795
American Herbal Products Association. Rooibos trademark abandoned. Published July 2005. Accessed September 14, 2022. https://www.ahpa.org/Files/Document%20Library/AHPA%20Guidance%20Documents/CA%20Prop%2065/05_0700_AHPAReport_RooibosExcerpt.pdf
Areo OM, Njobeh PB. Risk assessment of heavy metals in rooibos (Aspalathus linearis) tea consumed in South Africa. Environ Sci Pollut Res Int. 2021;28:59687-59695. https://doi.org/10.1007/s11356-021-14968-2
Awoniyi DO, Aboua YG, Marnewick J, Brooks N. The effects of rooibos (Aspalathus linearis), green tea (Camellia sinensis) and commercial rooibos and green tea supplements on epididymal sperm in oxidative stress-induced rats. Phytother Res. 2012;26(8):1231-1239. doi:10.1002/ptr.371722228422
Ayeleso A, Brooks N, Oguntibeju O. Modulation of antioxidant status in streptozotocin-induced diabetic male Wistar rats following intake of red palm oil and/or rooibos. Asian Pac J Trop Med. 2014;7(7):536-544. doi:10.1016/S1995-7645(14)60090-025063283
Azubuike NC, Okoli NO. Impact of rooibos tea on experimental model of high-fat diet-induced non-alcoholic fatty liver disease. PharacologyOnLine. 2020;2:175-182.
Baba H, Ohtsuka Y, Haruna H, et al. Studies of anti-inflammatory effects of Rooibos tea in rats. Pediatr Int. 2009;51(5):700-704. doi:10.1111/j.1442-200X.2009.02835.x19419525
Beltran-Debon R, Rull A, Rodriguez-Sanabria F, et al. Continuous administration of polyphenols from aqueous rooibos (Aspalathus linearis) extract ameliorates dietary-induced metabolic disturbances in hyperlipidemic mice. Phytomedicine. 2011;18(5):414-424. doi:10.1016/j.phymed.2010.11.00821211952
Breiter T, Laue C, Kressel G, Groll S, Engelhardt UH, Hahn A. Bioavailability and antioxidant potential of rooibos flavonoids in humans following the consumption of different rooibos formulations. Food Chem. 2011;128(2):338-347. doi:10.1016/j.foodchem.2011.03.02925212140
Canda BD, Oguntibeju OO, Marnewick JL. Effects of consumption of rooibos (Aspalathus linearis) and a rooibos-derived commercial supplement on hepatic tissue injury by tert-butyl hydroperoxide in Wistar rats. Oxid Med Cell Longev. 2014;2014:716832. doi:10.1155/2014/71683224738022
Chen W, Sudji IR, Wang E, Joubert E, van Wyk BE, Wink M. Ameliorative effect of aspalathin from rooibos (Aspalathus linearis) on acute oxidative stress in Caenorhabditis elegans. Phytomedicine. 2013;20(3-4):380-386. doi:10.1016/j.phymed.2012.10.00623218401
de Beer D, Malherbe CJ, Beelders T, Willenburg EL, Brand DJ, Joubert E. Isolation of aspalathin and nothofagin from rooibos (Aspalathus linearis) using high-performance countercurrent chromatography: sample loading and compound stability considerations. J Chromatogr A. 2015;1381:29-36. doi:10.1016/j.chroma.2014.12.07825614190
Department of Trade and Industry Republic of South Africa. Department of Trade and Industry Annual Report 2012/2013. September 6, 2013. Accessed September 14, 2022. https://www.gov.za/sites/default/files/gcis_document/201409/departmentoftradeindustryannualreport2013.pdf
Dludla PV, Muller CJ, Louw J, et al. The cardioprotective effect of an aqueous extract of fermented rooibos (Aspalathus linearis) on cultured cardiomyocytes derived from diabetic rats. Phytomedicine. 2014;21(5):595-601. doi:10.1016/j.phymed.2013.10.02924268738
Duke J, Bogenschutz-Godwin M, duCellier J, Duke P. Handbook of Medicinal Herbs. 2nd ed. CRC Press; 2002.
Fukasawa R, Kanda A, Hara S. Anti-oxidative effects of rooibos tea extract on autoxidation and thermal oxidation of lipids. J Oleo Sci. 2009;58(6):275-283.19430189
Gouws P, Hartel T, van Wyk R. The influence of processing on the microbial risk associated with Rooibos (Aspalathus linearis) tea. J Sci Food Agric. 2014;94(15):3069-3078. doi:10.1002/jsfa.671924789759
Han Z, Achilonu MC, Kendrekar PS, et al. Concise and scalable synthesis of aspalathin, a powerful plasma sugar-lowering natural product. J Nat Prod. 2014;77(3):583-588. doi:10.1021/np400844324354397
Hong IS, Lee HY, Kim HP. Anti-oxidative effects of Rooibos tea (Aspalathus linearis) on immobilization-induced oxidative stress in rat brain. Published online January 21, 2014. PLoS One. 2014;9(1):e87061. doi:10.1371/journal.pone.008706124466326
Huang SH, Tseng JC, Lin CY, et al. Rooibos suppresses proliferation of castration-resistant prostate cancer cells via inhibition of Akt signaling. Phytomedicine. 2019;64:153068. doi:10.1016/j.phymed.2019.15306831419729
Idriss MT, Abdelgadir AA, Nour AH. In vitro antiviral activity of rooibos tea (Aspalathus lineraris) leaves aqueous extract against influenza virus. Trop J Nat Prod Res. 2021;5(4):686-691. doi.org/10.26538/tjnpr/v5i4.16
Joubert E, Beelders T, de Beer D, Malherbe CJ, de Villiers AJ, Sigge GO. Variation in phenolic content and antioxidant activity of fermented rooibos herbal tea infusions: role of production season and quality grade. J Agric Food Chem. 2012;60(36):9171-9179. doi:10.1021/jf302583r22920220
Joubert E, de Beer D, Malherbe CJ, et al. Occurrence and sensory perception of Z-2-(beta-d-glucopyranosyloxy)-3-phenylpropenoic acid in rooibos (Aspalathus linearis). Food Chem. 2013;136(2):1078-1085. doi:10.1016/j.foodchem.2012.09.01423122165
Joubert E, Winterton P, Britz TJ, Gelderblom WC. Antioxidant and pro-oxidant activities of aqueous extracts and crude polyphenolic fractions of rooibos (Aspalathus linearis). J Agric Food Chem. 2005;53(26):10260-10267.16366725
Juráni M, Lamosová D, Mácajová M, Kostál L, Joubert E, Greksák M. Effect of rooibos tea (Aspalathus linearis) on Japanese quail growth, egg production and plasma metabolites. Br Poult Sci. 2008;49(1):55-64.
Kamakura R, Son MJ, de Beer D, Joubert E, Miura Y, Yagasaki K. Antidiabetic effect of green rooibos (Aspalathus linearis) extract in cultured cells and type 2 diabetic model KK-A mice. Cytotechnology. 2014;67(4):699-710. doi:10.1007/s10616-014-9816-y25410530
Kawano A, Nakamura H, Hata S, Minakawa M, Miura Y, Yagasaki K. Hypoglycemic effect of aspalathin, a rooibos tea component from Aspalathus linearis, in type 2 diabetic model db/db mice. Phytomedicine. 2009;16(5):437-443. doi:10.1016/j.phymed.2008.11.00919188054
Khan AU, Gilani AH. Selective bronchodilatory effect of Rooibos tea (Aspalathus linearis) and its flavonoid, chrysoeriol. Eur J Nutr. 2006;45(8):463-469.17080260
Kondo M, Hirano Y, Nishio M, Furuya Y, Nakamura H, Watanabe T. Xanthine oxidase inhibitory activity and hypouricemic effect of aspalathin from unfermented rooibos. J Food Sci. 2013;78(12):H1935-H1939. doi:10.1111/1750-3841.1230424261664
Krafczyk N, Glomb MA. Characterization of phenolic compounds in rooibos tea. J Agric Food Chem. 2008;56(9):3368-3376. doi:10.1021/jf703701n18399640
Ku SK, Kwak S, Kim Y, Bae JS. Aspalathin and Nothofagin from Rooibos (Aspalathus linearis) inhibits high glucose-induced inflammation in vitro and in vivo. Inflammation. 2015;38(1):445-455. doi:10.1007/s10753-014-0049-125338943
Ku SK, Lee W, Kang M, Bae JS. Antithrombotic activities of aspalathin and nothofagin via inhibiting platelet aggregation and FIIa/FXa. Arch Pharm Res. 2015;38(6):1080-1089. doi:10.1007/s12272-014-0501-725325928
Kwak S, Han MS, Bae JS. Aspalathin and nothofagin from rooibos (Aspalathus linearis) inhibit endothelial protein C receptor shedding in vitro and in vivo. Fitoterapia. 2015;100:179-186. doi:10.1016/j.fitote.2014.12.00225510322
Lee W, Bae JS. Anti-inflammatory effects of Aspalathin and Nothofagin from rooibos (Aspalathus linearis) in vitro and in vivo. Inflammation. 2015;38(4):1502-1516. doi:10.1007/s10753-015-0125-125655391
Lim WX, Gammon CS, von Hurst PR, Chepulis L, Mugridge O, Page RA. Hypoglycemic effects of antioxidant-rich plant extracts on postprandial glycemic responses in participants with prediabetes (GLARE study). Functional Foods Health Disease. 2021;11(11):604-626. doi:10.31989/ffhd.v11i11.829
Marnewick J, Joubert E, Joseph S, Swanevelder S, Swart P, Gelderblom W. 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;224(2):193-202.15914270
Marnewick JL, Rautenbach F, Venter I, et al. Effects of rooibos (Aspalathus linearis) on oxidative stress and biochemical parameters in adults at risk for cardiovascular disease. J Ethnopharmacol. 2011;133(1):46-52. doi:10.1016/j.jep.2010.08.06120833235
Marnewick JL, van der Westhuizen FH, Joubert E, Swanevelder S, Swart P, Gelderblom WC. Chemoprotective properties of rooibos (Aspalathus linearis), honeybush (Cyclopia intermedia) herbal and green and black (Camellia sinensis) teas against cancer promotion induced by fumonisin B1 in rat liver. Food Chem Toxicol. 2009;47(1):220-229. doi:10.1016/j.fct.2008.11.00419041360
Mazibuko SE, Muller CJ, Joubert E, et al. Amelioration of palmitate-induced insulin resistance in C2C12 muscle cells by rooibos (Aspalathus linearis). Phytomedicine. 2013;20(10):813-819. doi:10.1016/j.phymed.2013.03.01823639187
McAlpine MD, Gittings W, MacNeil AJ, Ward WE. Black and green tea as well as specialty teas increase osteoblast mineralization with varying effectiveness. J Med Food. 2021;24(8):866-872. doi:10.1089/jmf.2020.013933252307
McGaw LJ, Steenkamp V, Eloff JN. Evaluation of Athrixia bush tea for cytotoxicity, antioxidant activity, caffeine content and presence of pyrrolizidine alkaloids. J Ethnopharmacol. 2007;110(1):16-22.17045437
McKay DL, Blumberg JB. A review of the bioactivity of South African herbal teas: rooibos (Aspalathus linearis) and honeybush (Cyclopia intermedia). Phytother Res. 2007;21(1):1-16.16927447
Millar DA, Bowles S, Windvogel SL, Louw J, Muller CJF. Effect of rooibos (Aspalathus linearis) extract on atorvastatin-induced toxicity in C3A liver cells. J Cell Physiol. 2020;235:9487-9496. doi:10.1002/jcp.29756
Moosa S , Kasonga AE , Deepak V , et al. Rooibos tea extracts inhibit osteoclast formation and activity through the attenuation of NF-κB activity in RAW264.7 murine macrophages. Food Funct. 2018;9(6):3301-3312. doi:10.1039/c7fo01497j29790498
Muller CJ, Joubert E, Chellan N, Miura Y, Yagasaki K. New Insights into the efficacy of aspalathin and other related phytochemicals in type 2 diabetes-a review. Int J Mol Sci. 2022;23:356. doi:10.3390/ijms23010356
Muller CJ, Joubert E, de Beer D, et al. Acute assessment of an aspalathin-enriched green rooibos (Aspalathus linearis) extract with hypoglycemic potential. Phytomedicine. 2012;20(1):32-39. doi:10.1016/j.phymed.2012.09.01023083813
Muller CJ, Joubert E, Pheiffer C, et al. Z-2-(beta-D-glucopyranosyloxy)-3-phenylpropenoic acid, an alpha-hydroxy acid from rooibos (Aspalathus linearis) with hypoglycemic activity. Mol Nutr Food Res. 2013;57(12):2216-2222. doi:10.1002/mnfr.20130029423943314
Muller CJ, Malherbe CJ, Chellan N, Yagasaki K, Miura Y, Joubert E. Potential of rooibos, its major C-glucosyl flavonoids, and Z-2-(β-D-glucopyranosyloxy)-3-phenylpropenoic acid in prevention of metabolic syndrome. Crit Rev Food Sci Nutr. 2018;58(2):227-246.
Muvhulawa N, Dludla PV, Ziqubu K, et al. Rutin ameliorates inflammation and improves metabolic function: A comprehensive analysis of scientific literature. Pharmacol Res. 2022;178:106163. doi:10.1016/j.phrs.2022.10616335257898
Opuwari CS, Monsees TK. In vivo effects of Aspalathus linearis (rooibos) on male rat reproductive functions. Andrologia. 2014;46(8):867-877. doi:10.1111/and.1215824007336
Opuwari CS, Monsees TK. Reduced testosterone production in TM3 Leydig cells treated with Aspalathus linearis (Rooibos) or Camellia sinensis (tea). Andrologia. 2015;47(1):52-58. doi:10.1111/and.1222124387279
Pantsi WG, Marnewick JL, Esterhuyse AJ, Rautenbach F, van Rooyen J. Rooibos (Aspalathus linearis) offers cardiac protection against ischaemia/reperfusion in the isolated perfused rat heart. Phytomedicine. 2011;18(14):1220-1228. doi:10.1016/j.phymed.2011.09.06921982437
Park HJ, Park KC, Yoon KS. Effect of rooibos (Aspalathus linearis) on growth control of Clostridium perfringens and lipid oxidation of ready-to-eat Jokbal (pig's trotters). J Food Sci. 2014;79(12):M2507-M2515. doi:10.1111/1750-3841.1270125394229
Patel O, Muller C, Joubert E, Rosenkranz B, Louw J, Awortwe C. Pharmacokinetic and pharmacodynamic interaction between green rooibos extract and atorvastatin in mice [abstract P18]. British J Pharmacology. 2019;2981:P18.
Pedretti S, Peter J. Rooibos herbal tea reduces allergic basophil activation in adult atopic patients. J Ethnopharmacol. 2020;252:112353. doi:10.1016/j.jep.2019.11235331672527
Persson IA. The pharmacological mechanism of angiotensin-converting enzyme inhibition by green tea, Rooibos and enalaprilat - a study on enzyme kinetics. Phytother Res. 2012;26(4):517-521. doi:10.1002/ptr.358822095883
Pyrzanowska J. The toxic contaminants of Aspalathus linearis plant material as well as herb-drug interactions may constitute the health risk factors in daily rooibos tea consumers. Int J Environ Health Res. 2021:1-14. doi:10.1080/09603123.2021.200978034823434
Pyrzanowska J, Joniec-Maciejak I, Blecharz-Klin K, et al. Aspalathus linearis infusion affects hole-board test behaviour and amino acid concentration in the brain. Neurosci Lett. 2021;747:135680. doi:10.1016/j.neulet.2021.13568033529651
Reddy S, Mishra P, Qureshi S, Nair S, Straker T. Hepatotoxicity due to red bush tea consumption: a case report. J Clin Anesth. 2016;35:96-98.27871602
Sanderson M, Mazibuko SE, Joubert E, et al. Effects of fermented rooibos (Aspalathus linearis) on adipocyte differentiation. Phytomedicine. 2014;21(2):109-117. doi:10.1016/j.phymed.2013.08.01124060217
Sasaki M, Nishida N, Shimada M. A beneficial role of rooibos in diabetes mellitus: A systematic review and meta-analysis. Molecules. 2018;23:839. doi:10.3390/molecules2304083929642387
Schloms L, Smith C, Storbeck KH, Marnewick JL, Swart P, Swart AC. Rooibos influences glucocorticoid levels and steroid ratios in vivo and in vitro: a natural approach in the management of stress and metabolic disorders? Mol Nutr Food Res. 2014;58(3):537-549. doi:10.1002/mnfr.20130046324022885
Schloms L, Storbeck KH, Swart P, Gelderblom WC, Swart AC. The influence of Aspalathus linearis (Rooibos) and dihydrochalcones on adrenal steroidogenesis: quantification of steroid intermediates and end products in H295R cells. J Steroid Biochem Mol Biol. 2012;128(3-5):128-138. doi:10.1016/j.jsbmb.2011.11.00322101210
Sheik Abdul N, Marnewick JL. Fumonisin B1 -induced mitochondrial toxicity and hepatoprotective potential of rooibos: An update. J Appl Toxicol. 2020;40:1602-1613. doi:10.1002/jat.403632667064
Sheik Abdul N, Marnewick JL. Rooibos, a supportive role to play during the COVID-19 pandemic? J Funct Foods. 2021;86:104684. doi:10.1016/j.jff.2021.10468434422116
Shimamura N, Miyase T, Umehara K, Warashina T, Fujii S. Phytoestrogens from Aspalathus linearis. Biol Pharm Bull. 2006;29(6):1271-1274.16755032
Simpson MJ, Hjelmqvist D, Lopez-Alarcon C, et al. Anti-peroxyl radical quality and antibacterial properties of rooibos infusions and their pure glycosylated polyphenolic constituents. Molecules. 2013;18(9):11264-11280. doi:10.3390/molecules18091126424036515
Sinisalo M, Enkovaara AL, Kivisto KT. Possible hepatotoxic effect of rooibos tea: a case report. Eur J Clin Pharmacol. 2010;66(4):427-428. doi:10.1007/s00228-009-0776-720072844
Sirotkin AV. Rooibos (Aspalathus linearis) influence on health and ovarian functions. J Anim Physiol Anim Nutr (Berl). 2021;00:1–5. doi:10.1111/jpn.1362434402103
Smit SE, Manirafasha C, Marais E, Johnson R, Huisamen B. Cardioprotective function of green rooibos (Aspalathus linearis) extract supplementation in ex vivo ischemic prediabetic rat hearts. Planta Med. 2022;88(1):62-78. doi:10.1055/a-1239-923633285593
Smit-Van Schalkwyk M, Windvogel S, Strijdom H. Rooibos (Aspalathus linearis) protects against nicotineinduced vascular injury and oxidative stress in Wistar rats. Cardiovasc J Afr. 2020;31(4):81-90. doi:10.5830/CVJA-2019-05232031565
Snijman PW, Swanevelder S, Joubert E, Green IR, Gelderblom WC. The antimutagenic activity of the major flavonoids of rooibos (Aspalathus linearis): some dose-response effects on mutagen activation-flavonoid interactions. Mutat Res. 2007;631(2):111-123.17537670
Stalmach A, Mullen W, Pecorari M, Serafini M, Crozier A. Bioavailability of C-linked dihydrochalcone and flavanone glucosides in humans following ingestion of unfermented and fermented rooibos teas. J Agric Food Chem. 2009;57(15):7104-7111. doi:10.1021/jf901164219534535
Swanepoel ML. Salmonella isolated from rooibos tea. S Afr Med J. 1987;71(6):369-370.3563774
Tarirai C, Viljoen AM, Hamman JH. Effects of dietary fruits, vegetables and a herbal tea on the in vitro transport of cimetidine: comparing the Caco-2 model with porcine jejunum tissue. Pharm Biol. 2012;50(2):254-263. doi:10.3109/13880209.2011.59816922085278
Ulicná O, Vancová O, Waczulíkova I, et al. Does rooibos tea (Aspalathus linearis) support regeneration of rat liver after intoxication by carbon tetrachloride? Gen Physiol Biophys. 2008;27(3):179-186.18981533
van der Merwe JD, Joubert E, Richards ES, et al. A comparative study on the antimutagenic properties of aqueous extracts of Aspalathus linearis (rooibos), different Cyclopia spp. (honeybush) and Camellia sinensis teas. Mutat Res. 2006;611(1-2):42-53.16949333
Villaño D, Pecorari M, Testa MF, et al. Unfermented and fermented rooibos teas (Aspalathus linearis) increase plasma total antioxidant capacity in healthy humans. Food Chem. 2010;123(3):679-683.
Wang BJ, Huang SH, Kao CL, et al. Aspalathus linearis suppresses cell survival and proliferation of enzalutamide-resistant prostate cancer cells via inhibition of c-Myc and stability of androgen receptor. PLoS One. 2022;17(7):e0270803. doi:10.1371/journal.pone.027080335776912
Watt J, Breyer-Brandwijk MG. Medicinal and Poisonous Plants of Southern and Eastern Africa. 2nd ed. E & S Livingstone Ltd; 1962.

## Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer

Copyright © 2023 Wolters Kluwer Health