Whenever I read and learn about foods and health benefits of foods, I gig deeper into composition and ingredients of it.
We all know that drinking green teas are so good for us, but what’s in the green teas that is so health beneficial?
So today we will discover one of the green tea composites: L-Theanine.
I will simply reference you to the couple abstracts with simple health benefits explanation.
Just the fact, that L-Theanine crosses blood-brain barrier to calm anyone’s brain, is a huge positive affirmation for drinking more green teas.
Personally, I love purchasing my teas in a “loose, aka leaves teas” variety and steep my teas. After all, it is a Russian tradition to make teas and we even have special sets of cups and saucers for teas only.
I also love buying my teas from local providers, not only it helps local businesses, but it builds beautiful connection and friendships and most important, they carry the highest, purest and most tastiest teas and tea blends.
I will strongly encourage you to find your local tea shops, or tea vendors at the local farmers markets.
I raise my teacup, filled with freshly brewed green tea to our health and happiness.
Biological Psychology 74 (2007) 39–45
L-Theanine reduces psychological and physiological stress responses Kenta Kimura a,*, Makoto Ozeki b, Lekh Raj Juneja b, Hideki Ohira a
a Nagoya University Department of Psychology, Chikusa-ku, Nagoya, 464-8601, Japan b Taiyo Kagaku Co., Ltd., 1-3 Takara-machi, Yokkaichi, Mie 510-0844, Japan
L-Theanine is an amino acid contained in green tea leaves, which is known to block the binding of L-glutamic acid to glutamate receptors in the brain. Because the characteristics of L-Theanine suggest that it may influence psychological and physiological states under stress, the present study examined these possible effects in a laboratory setting using a mental arithmetic task as an acute stressor. Twelve participants underwent four separate trials: one in which they took L-Theanine at the start of an experimental procedure, one in which they took L-Theanine midway, and two control trials in which they either took a placebo or nothing. The experimental sessions were performed by double-blind, and the order of them was counterbalanced. The results showed that L-Theanine intake resulted in a reduction in the heart rate (HR) and salivary immunoglobulin A (s-IgA) responses to an acute stress task relative to the placebo control condition. Moreover, analyses of heart rate variability indicated that the reductions in HR and s-IgA were likely attributable to an attenuation of sympathetic nervous activation. Thus, it was suggested that the oral intake of L-Theanine could cause anti-stress effects via the inhibition of cortical neuron excitation.
Yoto et al. Journal of Physiological Anthropology 2012, 31:28
Effects of L-theanine or caffeine intake on changes in blood pressure under physical and psychological stresses
Ai Yoto*, Mao Motoki, Sato Murao and Hidehiko Yokogoshi
ORIGINAL ARTICLE Open Access
Background: L-theanine, an amino acid contained in green tea leaves, is known to block the binding of L-glutamic acid to glutamate receptors in the brain, and has been considered to cause anti-stress effects by inhibiting cortical neuron excitation. Both L-theanine and caffeine, which green tea contains, have been highlighted for their beneficial effects on cognition and mood.
Methods: In this study, we investigated the effects of orally administered L-theanine or caffeine on mental task performance and physiological activities under conditions of physical or psychological stress in humans. Fourteen participants each underwent three separate trials, in which they orally took either L-theanine + placebo, caffeine + placebo, or placebo only.
Results: The results after the mental tasks showed that L-theanine significantly inhibited the blood-pressure increases in a high-response group, which consisted of participants whose blood pressure increased more than average by a performance of a mental task after placebo intake. Caffeine tended to have a similar but smaller inhibition of the blood-pressure increases caused by the mental tasks. The result of the Profile of Mood States after the mental tasks also showed that L-theanine reduced the Tension-Anxiety scores as compared with placebo intake.
Conclusions: The findings above denote that L-theanine not only reduces anxiety but also attenuates the blood-pressure increase in high-stress-response adults.