Green tea, epigallocatechin gallate and the prevention of Alzheimer’s disease: Clinical evidence

Lange KW, Lange KM, Nakamura Y · Food Science and Human Wellness · 2022 July

DOI 10.1016/j.fshw.2022.03.002

Objective

To investigate the potential of green tea and its bioactive components in preventing Alzheimer's disease (AD).

Conclusions

The study concludes that while preclinical studies have shown neuroprotective effects of bioactive components in green tea, clinical evidence is currently insufficient to establish a causal relationship between green tea consumption and a reduced risk of AD.

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Insights

Bioactive components in green tea have demonstrated potential neuroprotective effects and might play a role in preventing Alzheimer’s disease.

In this study, the researchers focused on the potential preventative effects of bioactive compounds, specifically (-)-epigallocatechin-3-gallate, present in tea, on Alzheimer's disease (AD). This interest was based on recognition of the importance of lifestyle-related factors, including diet, in the primary prevention of AD. They compiled and analyzed the findings from various preclinical studies which pointed towards the neuroprotective qualities of these compounds. The results reveal an association between the consumption of green tea and a reduction in the risk of age-related cognitive decline and AD. However, these results do not establish a causal relationship. That is, while people who drink green tea appear to have lower rates of AD, the study cannot confirm that green tea consumption is the reason for this reduced prevalence. The researchers also emphasized that while the preventative effects of green tea were deduced from preclinical (animal) studies, human-based clinical trials yielded unsatisfactory evidence regarding tea's preventive or therapeutic effect on AD.