“Loss of Cognitive Function”
These words seem to sanitize what is, in reality, a profound loss. A loss of a person.
Not only mental functioning—but memory, personality, relationships, ways of dealing with the world. The intangibles that make us who we are.
A loss—with effects that are devastating, far-reaching, and unremitting.
After looking into a few studies on how tea—both green and black—seems to protect our cognition and our functional ability as we age, I might lightly say “pass the teapot,” but the reality? This is serious stuff.
Ongoing research seeks to quantify and maximize tea’s effects on health and cognition. What exactly in the tea protects brain function? How exactly does it work? Can this factor be isolated, concentrated, and then used medicinally for specific purposes?
The Magic of Polyphenols
This brings us to polyphenols—antioxidants that are naturally found in plants. And tea leaves, or Camellia sinensis, have a lot of polyphenols.
In Green Tea
When tea leaves are plucked, plant cells are damaged and the leaves immediately begin to oxidize. To stop this process and to produce green tea, the leaves are steamed or pan-fried. This keeps the polyphenols largely as flavanols or catechins. And it is these catechins that give green tea its color and vegetal flavor.
In Black Tea
To produce black tea, the Camellia sinensis leaves are more fully oxidized, which converts the simple polyphenols into more complex forms: theaflavin and thearubigin. Controlling the oxidation controls the appearance and flavor of black tea, with theaflavin providing bright taste and thearubigin complexity.
But the conversion of catechins into theaflavins does not reduce their antioxidant properties. In fact, one study has shown that green tea catechins and black tea theaflavins have the same antioxidant potency (Leung et al. 2001)!
What They Do for Us
Current research suggests that the antioxidant properties of polyphenols protect the brain in a slew of ways:
–protect the neurons from damage by free radicals
–help maintain neuron viability
–lower the risk of stroke
–lower the risk of depression
–protect against Alzheimer’s disease
–protect against toxins
–enhance cognitive function
Although research studies often are neither fully consistent nor conclusive, no matter what its oxidation level, tea seems to have health benefits that are real!
Does It Have to be Tea?
This begs the question that non-tea drinkers may well ask: are the benefits of tea such that everyone should drink tea? After all, most plants are beneficial for us. Is there anything about tea that makes it special? I’ll look into that a bit in the future.
Meanwhile, I Take No Chances: Another Cup of Tea Please!
–Leung, L. K., et al. “Theaflavins in Black Tea and Catechins in Green Tea Are Equally Effective Antioxidants,” Journal of Nutrition 131(9):2248–51. 2001.
–Massachusetts General Hospital. “Green Tea May Help Conserve Cognition, Cup by Cup,” Mind, Mood and Memory 8(6):4. 2012.
–Mukhtar, H., and N. Ahmad. “Tea Polyphenols,” American Journal of Clinical Nutrition 71(6):1698s–702s. 2000.
–Shen, W., et al. “Tea Consumption and Cognitive Impairment,” PLoS ONE 10(9):e0137781. 2015.
–Tomata, Y. et al. “Green Tea Consumption and the Risk of Incident Functional Disability in Elderly Japanese,” American Journal of Clinical Nutrition 95:732–39. 2012.
–Wang, Y., and C.-T. Ho. “Polyphenolic Chemistry of Tea and Coffee,” Journal of Agricultural and Food Chemistry 57:8109–14. 2009.