Research published in the American Journal of Respiratory and Critical Care Medicine (May 15, 2008; 177(10):1135–1141) explored whether green tea extract could help protect the brain from oxygen deprivation. The study was conducted in animals, not humans.
In this experiment, 106 rats were exposed to intermittent oxygen deprivation for two weeks, a model designed to mimic the hypoxic stress that occurs during sleep apnea. Half of the oxygen-deprived rats received a green tea extract, while the other half did not. Green tea extract is rich in polyphenols and is an effective antioxidant.
When tested, rats that received the green tea extract performed better on memory tasks than oxygen-deprived rats that did not receive the extract. In addition, markers of oxidative stress were significantly higher in the untreated group, suggesting greater oxidative damage in the brain.
Based on these findings, the authors proposed that the antioxidant compounds in green tea may help protect brain tissue from hypoxia-related oxidative stress. They suggested that this mechanism could be relevant to sleep apnea, a condition characterized by repeated reductions in oxygen delivery to the brain during sleep, and that green tea extract may play a role in reducing hypoxia-associated neurocognitive changes. These conclusions were exploratory and based on animal data.
