New research reveals that extracts from unfermented tea leaves of the rooibos bush (Aspalathus linearis) can help fight anxiety. The way the research team discovered this property of the plant’s extracts (ethanol rather than aqueous) is highly interesting—Zebrafish larvae.
The small striped freshwater fish has genes that are 80% similar to human genetic material known to trigger diseases. This is why Stellenbosch University’s Faculty of Medicine and Health Sciences rely on it in research to understand more about human neurological reactions.
In one part of the study, zebrafish larvae were stressed out by exposure to alternating bright lights and darkness. Then, the level of their anxiety was determined by the level of their hyperactive movements in the darkness mode.
When scientists submerged the larvae in rooibos tea, they found that it had an anxiolytic effect. They reached this conclusion on the basis of the lack of hyped movements in the dark, when compared with the fish that hadn’t been treated with rooibos tea before undergoing the test.
Scientists also learned that the green rooibos has certain anti-epileptic properties, mostly owing to the ability to influence an important calming neurotransmitter called GABA.
However, this isn’t the only reason to turn on your favorite tea kettle. The phenolic compounds in the plant were also shown to have neuroprotective effects on human cell cultures.
More precisely, rooibos seems to protect brain cells from oxidative stress that causes damage and aging. Also, high levels of antioxidants imply anti-inflammatory properties. Hence, researchers concluded unfermented rooibos bush leaves can serve as functional brain food.
In addition, green rooibos contains no caffeine at all. It also has a lighter and fresher taste than most kinds of tea, with no bitter undertones whatsoever.