You may recall hearing about how green tea contains a compound that can reduce the risk of developing Alzheimer’s disease. Until recently, however, experts have not understood how this benefit works. Now a Canadian team reports it has found an answer, and it involves epigallocatechin gallate (EGCG), a potent antioxidant and polyphenol found in green tea.
Specifically, EGCG disrupts the function of specific substances called beta-amyloid oligomers, which in turn stop the formation of beta-amyloid plaques-sticky pieces of proteins that accumulate in the brain and are believed to play a significant role in the development of Alzheimer’s disease.
Any promising findings regarding prevention would be most welcome, as it is estimated about 131.5 million people will have the disease by 2050. Let’s see what the researchers found.
An investigative team from McMaster University explored how EGCG impacts beta-amyloid plaque formation by using nuclear magnetic resonance. They discovered that minute binding molecules called beta-amyloid monomers form beta-amyloid oligomers. Over time, the oligomers can collect and form toxic plaques in the brain.
The addition of EGCG to the picture resulted in the polyphenol helping to remodel the beta-amyloid oligomers, which in turn prevented them from making harmful plaques. According to the lead author, Giuseppe Melacini, “we believe EGCG coats toxic oligomers and changes their ability to grow and interact with healthy cells.”
The findings of this study support previous research and also add to our knowledge about how EGCG could be used to help prevent Alzheimer’s disease. So, could enjoying a cup of green tea help ward off the development of this most common form of dementia?
It is too early to know for sure, but Melacini noted that since there’s no cure for the disease yet, early intervention and preventive steps are our best bet. “That could mean using green tea extracts or their derivatives early on, say 15 to 25 years before any symptoms ever set in.” One significant consideration, however, is that EGCG does not easily reach the brain, so researchers will need to modify the polyphenol to make this possible. In the meantime, however, green tea and EGCG offer many other health benefits, so set the kettle to boil and enjoy!
How to enjoy green tea
The general rule is 5 grams of green tea leaves (1 tsp) or pearls per 8 ounces of water. Place the leaves or pearls in a tea ball or sieve in a cup. Pour hot water (about 180°F) into the cup over the leaves. Allow to steep for 2 to 3 minutes; longer will result in bitter tea. Remove the tea ball or sieve and enjoy your tea!
[Editor’s Note: We love to enjoy a cup of Bigelow Tea, they have a variety of green tea options. Also, CogGevity has a brain health supplement that includes Decaffeinated Green Tea Extract as one of it’s ingredients.]
Ahmed R et al. Molecular mechanism for the (-)-epigallocatechin gallate-induced toxic to nontoxic remodeling of AB oligomers. Journal of the American Chemical Society 2017 Oct 4; 139(39): 13720-34
Alzheimer’s Disease International. Dementia statistics
Cascella M et al. The efficacy of epigallocatechin-3-gallate (green tea) in the treatment of Alzheimer’s disease: an overview of pre-clinical studies and translational perspectives in clinical practice. Infectious Agents and Cancer 2017 Jun 19; 12:36