When I was eighteen years old I had gone out to eat one day with my girlfriend (eventually who became my wife). Up to that point in my life I had never tasted a tomato. That day I decided now was the time. Much to my delight I enjoyed the taste of a tomato very much.
I then lamented over the fact that I had wasted many years not having had the opportunity to eat this delicious food. The same thing happens to me from time to time when I go out to dinner and order a strange bottle of wine that turns out to be quite tasty. When you come upon a new drink or food product, it can be enjoyable and a lot of fun. Well, the same thing happens to me when I discover new nutrients.
Recently I began reading about theanine. This amino acid is a component of green tea leaves and, much to my surprise and delight, appears to be extremely beneficial. There have been articles dating back for over two decades studying the effects of this nutrient.
The average life span of Japanese in the year 2000 was almost 85 years for women and over 77 years for men. With people living longer in Japan there has been concern about many of the degenerative disorders of aging including dementia, stroke, etc. In one epidemiologic study, it was found that the incidence of stroke was significantly lower in people who consumed more than five cups of green tea per day. The article paid special attention to theanine (chemical name gamma-glutamylethylamide).
Over the years, researchers have found that theanine behaves in a manner similar to the excitatory neurotransmitter glutamic acid. Glutamic acid can actually be toxic to brain cells, although theanine appears to have a neuroprotective effect. In one study performed in cultured rat neurons (nerve cells), these cells were destroyed with the application of glutamic acid. However, when the cultures were first pretreated with theanine, the nerve cells were protected. Theanine appears to bind to glutamate receptors on the neurons, thereby protecting them. In addition theanine appears to increase GABA levels in the brain, an inhibitory neurotransmitter.
Other studies in the medical literature have suggested that theanine can also have a calming effect. Studies have shown it can actually counteract the effects of caffeine. For many centuries people have consumed tea for its relaxant effects.
This may be related to increasing GABA levels in the brain. GABA also appears to optimize brain cell transmission and may actually improve memory and overall mental function. Theanine has been used for years for premenstrual syndrome (PMS). In a study performed in Japan, women consuming 200 mg daily of theanine reportedly had a lower incidence of PMS. Animal studies have also shown it can also have some anti-tumor activity as well.
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