Risks and Benefits of Red and Green Rooibos Tea

Black, green, and white teas are all made from the same evergreen plant. Herbal tea, on the other hand, involves pouring water over any plant in the world other than the tea plant. In my book How Not to Age, I covered hibiscus and chamomile tea in my chapters on boosting AMPK and blocking inflammation. Are there any other notable herbal teas that may have anti-aging properties?

Rooibos, also known as red tea, is a caffeine-free herbal tea grown in a mountainous region of South Africa. It has been shown to increase the lifespan of C. elegans by as much as 23 percent under conditions of oxidative stress, presumed to be due to its antioxidant properties. In a head-to-head comparison of fifteen herbal teas, rooibos came in at number two (after dandelion) for in vitro antioxidant power.

Green rooibos—analogous to green tea— worked better in the C. elegans study than red rooibos, which is the commercially more common oxidized form (akin to black tea). Green rooibos tea has about twice the antioxidant capacity compared to red, though both similarly increase the blood antioxidant capacity after consumption. Within six weeks, rooibos intake can decrease markers of oxidative damage and even drop LDL cholesterol by nearly 27 points (mg/dl) compared to control, but the dose used (six cups (1440 ml) a day) is more than most people drink. No smaller quantity has apparently yet been put to the test.

If you want to try it at home, though the “optimal cup” is said to require 10 minutes of steeping, it appears extraction plateaus at five minutes; so, more time doesn’t seem necessary. The traditional method of brewing is to simmer the rooibos, which does appear to improve its antioxidant capacities compared to hot or cold steeping. The practice fell into disfavor with the advent of tea bags for convenience in the 1960s.

The same bag transition happened to black tea—jumping from 5 percent in 1960 in the U.K. to more than 95 percent by 2007—but that switch may have actually had favorable consequences. Because the tea in bags tends to be chopped so much finer than loose tea, the extra surface area improves the extraction. It only takes two minutes of infusion time to extract the same quantity of tea compounds from bagged black tea that it would take ten minutes to extract from loose leaf black tea. Ideally, we should steep for more than two minutes, though. Flavonoid extraction from black tea isn’t complete until about minute four. Green tea is ideally maybe brewed for three minutes at 85oC (for both optimum nutrition and taste) and white tea at 98ºC for seven min. (White tea brewed from bags also results in almost twice the antioxidant capacity of the loose leaf).

Rooibos has an excellent safety record, though there have been four cases reported in the medical literature of liver toxicity associated with rooibos use, the most convincing of which involved two separate hospitalizations for acute hepatitis following a resumption of rooibos consumption. All cases resolved without incident once the patients stopped drinking rooibos, but as with any new tea, herb, supplement, or drug, immediately consult your healthcare practitioner if you develop symptoms of liver trouble, such as abdominal pain, dark urine, or jaundice (which is yellowing of the skin or eyes).

One nice bonus to rooibos is that it’s effectively fair trade by definition. Starting in 1993, nearly every country on the planet ratified the Convention on Biological Diversity, a breakthrough in global environmental policymaking that aimed to conserve biodiversity by rewarding Earth’s custodians with fair and equitable benefit sharing. And the rooibos benefit sharing agreement was the first industry-wide agreement to be formed with indigenous peoples in accordance with the Convention.