Aspalathus linearis is a member of the Fabaceae family. It’s classified as a cape gorse and is native to the winter rainfall areas of South Africa. The species that are used to make Rooibos tea are predominantly native to the Western Cape’s mountainous Cedarberg region. The plant typically grows either erect or as a spreading shrub and can reach heights of up to 2 metres. It has stalkless 1 mm thick, 15 to 60 mm long needle-like green leaves that are often densely clustered. It flowers in spring through to early summer; the flowers are yellow and can grow either in solitary splendour or in a cluster on branch tips. They produce a small lance-shaped pod with one or two hard seeds.
Aspalathus linearis is not on any endangered list but its natural habitat is under increasing threat, leading to a reduction in native populations. Wild populations of the plant have also been subjected to unregulated harvesting, overgrazing, climate change, and invasion of habitat by other plants. Yet, despite its attractiveness Aspalathus linearis hasn’t yet become a popular garden plant, as it’s not easily propagated. The seeds need special treatment to make them germinate and they require an acidic sandy soil. There are however a growing number of Aspalathus linearis plantations as its commercial value increases. These are predominantly located in the Olifants, Breede, and Hex River valleys where the soil is the required acidic sand.
How To Drink Rooibos Tea
The primary method of consumption is as a tea, brewed and drunk like ordinary black tea with milk and/or sugar added according to taste. Rooibos tea is made from the leaves of the plant. They’re harvested then fermented, which turns them the red/brown colour that gives the tea its more common names of red bush tea, or red tea. A green version of the tea using unfermented leaves is also available and contains more antioxidants than the fermented version.
The plant has a long history of use in its native South Africa. It has many anecdotal benefits including as a source of antioxidants that are valuable for helping protect against stroke, heart disease, and cancer. Then again, most antioxidants provide similar benefits! However, unlike ordinary black and green tea, rooibos tea is an herbal tea and doesn’t contain caffeine, making it an ideal and refreshing alternative to more traditional caffeine containing brews. It is also a good alternative for those who avoid caffeine either through choice or for medical reasons.
Rooibos Tea – Busted And Confirmed Myths
Vitamin and mineral content – apart from copper and fluoride, and antioxidants, rooibos tea doesn’t actually contain many of the vitamins and minerals often attributed to it.
Tannins – rooibos tea is lower in tannins than either black or green tea. Tannins interfere with some nutrient absorption, notably iron.
Oxalic acid – rooibos tea is oxalic acid free. Oxalic acid in high doses can increase the risk of developing kidney stones so rooibos tea is a good alternative to black or green tea if you have kidney problems.
Antioxidants – rooibos tea contains the antioxidants aspalathin and quercetin. This study found some evidence to suggest that quercetin in black tea is associated with a lower incidence of heart disease in high-risk groups. A growing body of research into aspalathin indicates it could be a valuable inclusion in some types of drugs. It’s shown potential for treating diabetes, hypertension, and obesity along with having significant antioxidant, cardio-protective, hypouricaemic, and antimutagenic properties. Aspalathus linearis is currently the only known source of aspalathin. It’s important to note though that the fermenting process significantly reduces the content of these and other plant phytochemicals in rooibos. Therefore, if you want the full benefits you need to use the unfermented product. Even so there’s also evidence that the body either only minimally absorbs many of the antioxidants in rooibos, even green rooibos tea, or they’re very short-lived.
Cholesterol and heart health – this study found that some antioxidants in rooibos tea, notably quercetin, may be associated with a lower risk of mortality from heart disease. Another related study done with people at high risk of heart disease confirmed their lipid profile and redox status both improved after regular consumption of rooibos tea. There were no changes in people not at risk of heart disease.
Blood pressure – studies like this one found that consuming rooibos tea was able to inhibit the activities of angiotensin-converting enzyme (ACE). This is an enzyme involved in raising blood pressure. It converts angiotensin I to angiotensin II, an active vasoconstrictor that catalyses the narrowing of blood vessel walls leading to an increase in blood pressure. Interestingly, the study showed there were no increases in blood levels of nitric oxide after consuming any of the teas involved in the study (green tea, rooibos tea, and black tea), meaning there was no corresponding change in actual blood pressure.
Cancer – invitro (test tube) studies on antioxidants contained in rooibos tea show promising results for destroying cancer cells and inhibiting the growth of tumours in mice. However, the two antioxidants targeted by these studies, quercetin and luteolin, make up only a small fraction of the total antioxidant content in a cup of rooibos tea. Therefore, quercetin in particular may not be present in sufficient quantities in rooibos tea, or in a readily absorbable form, to have a truly beneficial effect in humans.
Type 2 diabetes – we mentioned earlier that Aspalathus linearis is currently the only known source of the antioxidant aspalathin. Animal studies have linked aspalathin with improved glucose metabolism. The findings are significant for people with hypoglycaemia and/or glucose intolerance ie type 2 diabetics and people at risk of developing it.
Rooibos tea consumption has also been anecdotally linked with a range of other health benefits including improved bone health, better digestion, enhanced sleep, alleviation of allergies, reduced headaches, and colic. However, studies (animal or human) into any of these reputed benefits is either scarce or non-existent. This doesn’t necessarily mean rooibos tea doesn’t help any of these conditions. It just means there haven’t been any scientific studies done yet.
Conclusions We Can Draw About The Health Benefits Of Rooibos Tea
The biggest conclusion is that a lot more research is needed to confirm, or otherwise, nearly all the reputed health benefits of rooibos tea. Whilst some studies are promising, there nevertheless needs to be more work done even in these areas before any definitive claims can be made around its benefits for human health. Furthermore, much of the research into lesser-known benefits thus far has been done on animals, or invitro, not in humans. However….as is the case with a lot of traditional and alternative therapies – just because the research hasn’t been done yet to substantiate their effectiveness in humans doesn’t necessarily mean they don’t work!