Researchers in Japan conducted a study to evaluate the potential cognitive benefits of matcha green tea for older adults. While matcha green tea may help with social cognition and sleep, the study did not find a connection between matcha and other cognitive improvements such as memory and executive functioning. Matcha green tea is high in vitamins and minerals, including vitamins C and E, magnesium, and potassium, as well as bioactive compounds like theanine and catechins. The researchers recruited 99 participants aged 60 to 85 and observed them for 12 months, administering cognitive assessments, neuroimaging, and monitoring their cognitive functioning levels.
The researchers randomly assigned participants to a matcha or placebo group, ensuring a balance based on age and dementia risk. Participants in the matcha group took 2 grams of green tea via a capsule daily, while the placebo group took a capsule with corn starch. The study found that participants in the matcha group did not show improvement in broader cognitive functioning but did show improvement in social cognition and sleep. The results indicated that the theanine in matcha may have contributed to improved sleep quality, which is important for overall health in older adults. Additionally, improvements in social acuity in the test group were promising, as poor social communication can be an early indicator of dementia.
Ralph Waldo, MD, an integrative medicine practitioner, noted that the high theanine content in matcha is likely key for the sleep benefits seen in the study. Waldo also mentioned that the catechins in matcha may protect social cognition by decreasing brain inflammation and stimulating new neural connections. However, more studies are needed to confirm matcha’s precise effects before recommending it as an intervention for mild cognitive impairment. Clifford Segil, DO, a neurologist, expressed curiosity about how matcha impacts sleep, as the study found that matcha improved sleep quality. Segil suggested that the time of day matcha is consumed may impact its effects on sleep, highlighting the importance of studying the potential mood benefits of matcha consumption.
While matcha green tea may not have a future as a standalone dietary intervention for dementia, it could potentially have positive effects on sleep quality and social cognition. The study results suggest that theanine and catechins in matcha may play a role in improving these cognitive functions in older adults. Further research is needed to explore the specific effects of matcha on cognitive health and to determine whether it could be a viable intervention for cognitive decline. Matcha green tea remains a popular and beneficial beverage, offering potential health benefits beyond cognitive functions.Participants in this group showed improvements in recognizing facial expressions and understanding word meanings.