Rooibos
Aspalathus linearis
Description
overall appearance
An erect, branching, broom-like shrub growing 1–2 m tall with fine, needle-like green leaves that turn red-orange on fermentation. Wild plants have fine, wiry foliage; cultivated plants are denser and more uniform.
roots
Woody taproot with nitrogen-fixing root nodules (symbiotic Bradyrhizobium); roots enable the plant to thrive in nutrient-poor fynbos soils; not used medicinally
stem
Erect, wiry, multi-stemmed; stems thin (3–6 mm diameter); green when young, turning brown; bark peels on mature stems
leaves
Needle-like, terete (round in cross-section), 15–60 mm long and about 1 mm wide; bright green when fresh; arranged alternately; transformed to red-orange color during fermentation process
flowers
Small, yellow, pea-shaped (papilionaceous), 5–8 mm long; borne in axillary clusters; typical legume flower; blooms August–September
fruits/seeds
Small, single-seeded pods 5–8 mm long; indehiscent; tan-brown when ripe; 1 seed per pod
Active Compounds
Traditional Uses
- Khoikhoi and San peoples: harvested wild rooibos as a beverage and medicine long before European contact; used as a digestive remedy
- Afrikaner farming communities: adopted as a tea substitute during WWII when imported teas were unavailable
- South African folk medicine: used for infantile colic, eczema, and skin allergies in babies — mothers added rooibos tea to infant formula
- Traditional use as an anti-spasmodic for digestive cramps and nausea
- Application of cooled tea to the skin for sunburn, eczema, and insect bites
- Traditional use for insomnia as a mild sedative tea
- Used as a high-iron, caffeine-free tea for pregnancy in Afrikaner tradition
Modern Applications
- Antioxidant protection: ORAC value and FRAP assay show potent radical scavenging; fermented and green forms differ significantly
- Antidiabetic: aspalathin shown to reduce glucose absorption, stimulate insulin secretion, and activate AMPK in cell and animal models
- Cardiovascular protection: quercetin and luteolin glycosides inhibit LDL oxidation and reduce arterial inflammation
- Skin benefits: topical aspalathin reduces UV-induced oxidative damage and supports collagen synthesis
- Anti-cancer: in vitro studies show inhibition of cancer cell lines (colon, prostate) via apoptosis induction and COX-2 inhibition
- Liver protection: aspalathin attenuates hepatic lipid accumulation in high-fat diet animal models
- Infantile colic: survey studies and small clinical reports support traditional use; safe for infants
- Caffeine-free beverage with low tannins: does not inhibit iron absorption, suitable for anemia-prone populations
⚠️ Safety Information
Contraindications
- Known hypersensitivity to Fabaceae/legume family (rare cross-reactivity possible)
- Hormone-sensitive cancers: phytoestrogenic activity debated; precautionary caution warranted
- Pre-surgery: mild antiplatelet effects from quercetin; discontinue 1 week before surgery
- Kidney stones (calcium oxalate type): moderate oxalate content with very high intake
Side Effects
- Generally considered extremely safe with no significant side effects at normal beverage consumption
- Rare contact dermatitis with topical application
- Mild estrogenic effects reported in vitro; clinical significance unknown
- Excessive intake (>6 cups/day): possible mineral imbalances from fluoride content
Drug Interactions
- Antidiabetic agents: aspalathin may enhance glucose lowering; monitor for hypoglycemia
- Anticoagulants (warfarin): quercetin antiplatelet activity may mildly enhance bleeding time
- Chemotherapy: CYP1A2 and CYP2C8 inhibition in vitro; potential for drug-herb interaction
- Iron chelation: unlike black tea, rooibos does not significantly inhibit iron absorption — actually compatible with iron supplementation
Parts Used
- Leaves and stems (fermented/oxidized, producing classic red rooibos)
- Green (unfermented) leaves and stems (higher aspalathin content)
- Whole aerial parts (harvested and chopped for processing)
Preparation Methods
Fermented (red) rooibos tea: 1.5–2 g dried herb per 200 mL boiling water, steep 5–7 minutes; 3–6 cups daily
Green (unfermented) rooibos tea: higher aspalathin; brewed same as red; more grassy flavor
Standardized green rooibos extract (standardized to aspalathin): 100–300 mg twice daily
Rooibos extract capsules: 200 mg standardized extract once daily
Topical cream (0.5–1% rooibos extract): applied to skin twice daily for eczema and sun damage
Cold-brewed concentrate: 20 g per liter, cold brew 12 hours — higher flavonoid yield than hot brew
Related Plants
Alfalfa
Medicago sativa
Astragalus
Astragalus membranaceus
Fenugreek
Trigonella foenum-graecum
Buchu
Agathosma betulina
Andrographis
Andrographis paniculata
Bacopa
Bacopa monnieri