Drink Away Your Stress

Drinking a nice hot cup of green tea can almost always make you feel better. But did you know that certain natural components of green tea have a direct effect on the body, increasing relaxation, easing depression and otherwise improving the mood? A growing body of evidence indicates that both green tea catechins and theanine, an amino acid found in green tea, can bring about positive changes to both body and mind.

Animal studies have found that the catechins increase insulin sensitivity, which means they help insulin do a better job of delivering glucose to the cells, including the cells of the brain. This is important because the brain runs on glucose, and when glucose levels fall too low, you can become depressed, fatigued, irritable and just plain moody. (Just think about how your mood disintegrates when you get overly hungry!)

But perhaps the most important mood enhancer found in green tea is theanine, the amino acid that gives the tea its mellow taste. Theanine has been shown to reduce mental and physical stress and promote feelings of relaxation. One human study found a significant increase in alpha-brain wave activity (that "relaxed yet alert" state cultivated in yoga class) after volunteers took 200 mg of theanine dissolved in water.¹ In another human study, theanine decreased two of the body’s responses to stress – heart rate and salivary immunoglobulin A.² And in animals given an intravenous dose of theanine following a dose of caffeine, the theanine calmed the "jittery" effects of the caffeine.³ No wonder you don’t get the same "buzz" from green tea that you do from other caffeine-containing drinks!

Tests performed on animals give two clues as to how theanine affects the brain and helps improve the mood. First, it significantly increases the brain’s levels of dopamine and serotonin, neurotransmitters that are linked to a sense of well-being. And second, theanine releases GABA (gamma amino butyric acid) in the brain, which calms brain over-excitation, eases anxiety and promotes relaxation.

Theanine works best at doses of 50-200 mg, with effects typically being felt within 30 minutes of ingestion and lasting for 8-10 hours. Coincidentally, there’s about 50 mg. of theanine in one cup of green tea. So have a cup and relax!