Quick Relief from Anxiety and Stress Without Tranquilizer DrugsAugust 2007
By Tiesha D. Johnson, RN, BSN
Theanine vs. Xanax®: Comparison of Effects
One of the most compelling studies on theanine was published in 2004. In a double-blind, head-to-head comparison study, investigators compared theanine with alprazolam (Xanax®), a commonly prescribed anxiolytic (anti-anxiety) drug.27 Each of 16 healthy human volunteers took either 1 mg alprazolam, 200 mg theanine, or a placebo on separate occasions; thus, all participants were tested with all three treatments. Following each dose, the researchers obtained behavioral measures of anxiety in all participants, both before and after an experimentally-created state of anxiety.
The results were nothing short of remarkable. Theanine, but not alprazolam or the placebo, induced relaxing effects that were evident at the initial measurement of whether a person felt tranquil versus troubled. This study is even more impressive when the dose of alprazolam is taken into consideration. One milligram is a substantial dose of this medication—generally, most people use just 0.25 to 0.5 mg of alprazolam as a bedtime sleep aid. Theanine’s superior performance to a potentially habit-forming medication is truly stunning good news.27
The dramatic effects of theanine have been further explored in several studies published just this year. A group of Japanese researchers studied the effects of theanine on psychological and physiological stress responses in humans.3 The researchers assigned a mental arithmetic task to each of 12 participants on four separate occasions, inducing so-called “math anxiety.” On one occasion, the subjects took theanine at the beginning of the test, on another they took the supplement halfway through, on a third they took a placebo that was identical to the supplement, and on a fourth they took nothing at all.
Astonishingly, even this extremely short-term use of theanine had remarkable effects on manifestations of anxiety. Subjects using theanine experienced a reduction in heart rate in response to the math testing, compared with those receiving placebo. Analysis of heart-rate variability suggested that theanine modulated activation of the sympathetic nervous system, the part of the nervous system that produces the “fight-or-flight” response. Because the sympathetic nervous system stimulates the release of adrenalin and triggers the first steps in the stress response that eventually leads to elevated stress hormone levels, keeping this system in check may help avert the deleterious long-term health consequences of stress.3
Theanine Supports Cognitive Function
A growing body of research suggests that theanine may be a powerful tool in boosting cognitive function. Theanine may work via several mechanisms of action to help keep the mind sharp.30
A 2007 report on theanine provides a detailed look at exactly how theanine works to improve cognition. New York-based researchers affiliated with the US Air Force were interested in “mapping” exactly where theanine produces effects in the brain.31 Previously, scientists have noted that when a person concentrates attention on a task, an electroencephalogram (EEG) study will show increased brain waves in the “alpha” region of the EEG spectrum.32,33 The Air Force investigators sought to determine whether theanine might cause changes in the important alpha region of the EEG during tasks that involve selective focus, indicating enhanced ability to perform attention-requiring tasks.31
While study subjects performed a standard task requiring focused attention, the researchers gathered data from EEG electrodes. As expected, the subjects showed significant increases in their alpha brain wave activity while concentrating on the tasks. When the subjects took theanine prior to the task, they showed a surprising decrease in alpha wave background activity, but a prominent increase in the important alpha activity related to the attention-requiring tasks.31 This critical result suggests that theanine has important and specific effects on the brain circuits involved in focusing attention on critical tasks.
An innovative Japanese study corroborates theanine’s ability to support essential brain function. Study participants who chewed gum containing 200 mg of theanine displayed significant increases in brain wave activity associated with focus and attention, as compared with individuals who chewed gum that did not contain theanine.34 This study suggests that theanine has the ability to promote attention to vital tasks, while minimizing interference from distracting outside stimuli—a finding that may have a wealth of important applications. These potential applications of theanine include enhancing concentration and performance in stressful situations, and potentially helping manage conditions such as attention-deficit disorder.
Growing evidence suggests a potential role for theanine in averting the most dreaded cause of memory loss—Alzheimer’s disease. Recent data have shown that theanine—along with other phytochemicals derived from green tea—promotes the activity of an enzyme that breaks down the harmful beta-amyloid protein, which is commonly found in the brains of Alzheimer’s patients.35 This promising preliminary study suggests that theanine could offer crucial protection against the brain changes that precede Alzheimer’s disease.
Other Benefits of Theanine
While theanine has received the most attention for its anxiety- and stress-relieving effects, this versatile natural agent is also attracting attention for its many other potential benefits.
Theanine may offer important support for healthy blood pressure levels. When scientists administered theanine to laboratory rats prone to high blood pressure, the animals displayed a significant drop in blood pressure. Notably, theanine did not cause any changes in rats with normal blood pressure. These findings suggest that theanine may benefit those with elevated blood pressure, while maintaining blood pressure levels that are already within a healthy range.36
Theanine may have further applications in promoting healthy weight management. When researchers studied body weight changes in laboratory mice in response to supplementation with the green tea constituents catechins, theanine, and caffeine, they found remarkable effects.37 The green tea-derived supplements notably modulated the tendency to gain weight and abdominal fat. In addition, the theanine-containing supplements reduced serum fatty acids. The researchers concluded that caffeine and theanine together “were responsible for the suppressive effect of green tea powder on body weight gain and fat accumulation.”
Theanine may find important use as an adjuvant cancer therapy. Scientists now know that theanine enhances the activity of certain chemotherapy drugs, while minimizing their destructive effects on healthy tissues. Theanine can increase the concentration of the drug doxorubicin (Adriamycin®) in tumors by suppressing a transport system that tumor cells normally use to rid themselves of the drug. Theanine also reduces tumor cell content of antioxidants that could reduce the drug’s destructive action on the cancer cells.38,39 While highly promising, further investigation is needed to fully evaluate the interaction between theanine and various cancer therapies.
Together, these findings suggest a host of new areas for exploration of theanine’s life-enhancing properties.
Safety and Dosage
Theanine is used in daily dosages ranging from 100-400 mg. There are no known adverse reactions associated with theanine. Pregnant women and nursing mothers should avoid theanine supplements until more is know about its effects. Theanine may enhance the anti-tumor effects of doxorubicin and idarubicin. The use of theanine supplements with cancer chemotherapeutic agents should only be conducted under medical supervision.18
The suggested dose of lemon balm is 300 mg, once or twice daily. Lemon balm may be used in the morning to address daytime anxiety, or may be used in the evening to support relaxation and sleep. There are no known contraindications to using lemon balm.16
Complementary Benefits of Theanine and Lemon Balm
Both green tea and lemon balm have centuries-old reputations as beneficial therapies for anxiety, stress, and impaired cognition. Together, these soothing natural agents hold promise in restoring the relaxed focus and mental clarity that are so easily eroded by the stressors of modern life. Further, these plant-derived remedies may even help stave off the cognitive decline associated with aging.
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