Green Tea: Relaxing and Beneficial
It’s always a good time to optimize your immunity, and green tea is one kitchen food I highly recommend. Since ancient times green tea has been considered a health-promoting beverage, and to this day there’s a ton of research looking at green tea and immune health.
Green tea is full of super ingredients, and its most relevant in regard to health are the polyphenols; the most important polyphenols are flavonoids; the most important flavonoids are catechins. The catechins comprise 80-90% of the flavonoids and around 40% of the water-soluble solids in green tea. Green tea contains more catechins than the other teas, mainly because of the way it’s processed after harvesting. Of the four main catechins found in green tea, Epigallocatechin Gallate (EGCG) is the most abundant (~60%) and the most studied for health.
The Flavonoids and EGCG in Green Tea Provide Many Impressive Health Benefits.
#1) Epigallocatechin gallate, EGCG, is a catechin found in green tea. Catechins are part of a group of plant compounds known as polyphenols, and EGCG gets a lot of attention for its potential positive impact on health. EGCG is a strong antioxidant capable of supporting normal cell function because it reduces oxidative stress and damage.
#2) EGCG is a zinc ionophore. The mineral, zinc, has a difficult time making it past cell walls and into cells of the body. A zinc ionophore helps shuttle zinc past the cell surface membrane, into the inner cell where it can effectively offer immune supporting effects.
#3) Green tea contains two types of flavonoids, which are some of the most potent antioxidants. Flavonoids help maintain a normal inflammatory response, promote the body’s innate resistance to pathogens, support seasonal allergies, and help remove damaging free radicals. Flavonoids also support heart health.
#4) EGCG is known to support a normal, healthy inflammatory response including when triggered by immune cells.
#5) Green tea contains L-theanine, a neurologically active amino acid present almost exclusively in the green tea plant. L-theanine is able to cross the blood-brain barrier and supports alpha brain wave production – the same brain bandwidth seen during the deepest states of meditation. In addition, L-theanine combines with caffeine in a way that produces relaxed alertness. L- theanine has a similar chemical structure to glutamate, which is a neurotransmitter related to memory. L-theanine is the main component responsible for the exotic savory taste of green tea known as "umami."
#6) Green tea is being studied as a potent advocate of brain health and memory support. Although the studies differ widely in technique, all focus on ways EGCG effects important areas of the brain.
#7) If you’re looking to sip some EGCG, matcha green tea, green tea, and white tea have the highest concentration of EGCG. Oolong tea the ‘middle’ amount, and black tea the least amount. Personally, I love matcha tea.
Introduce yourself to green tea by substituting a cup of green tea for a cup of coffee or include it as an afternoon treat. A single cup (8 ounces or 250 ml) of brewed green tea typically contains about 50-100 mg of EGCG.
Note: EGCG supplements are considered safe for most people but high doses may affect liver function. Researchers suggest consuming green tea capsules if you aren't interested in drinking green tea or want a more concentrated option.
Along with green tea, very small amounts of EGCG can be found in apples, avocados, blackberries, cranberries, plums, onions, pecan nuts and hazelnuts.
I hope you will soon be enjoying the health benefits of this delicious beverage soon!
In Health and Happiness,
Kelly Harrington, MS, RDN
Registered Dietitian Nutritionist for Healthy Goods
- Rosenberg, Irwin H., MD. "Green Tea Protects Brain Cells."Tufts University Health & Nutrition Letter31, No.4 (June 2013): 7. Print.
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- Hyunge, Suk-Joon, DeToma, Alaina S., Brender, Jeffrey R., et al. Insights into antiamyloidogenic properties of the green tea extract (−)-epigallocatechin-3-gallate toward metal-associated amyloid-β species.PNAS 2013 110 (10) 3743-3748
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