Botanical ingredients supplier Ethical Naturals Inc. (San Anselmo, CA) has announced the completion of a new, unpublished clinical study1 that it says demonstrates the stress-reduction potential of its proprietary L-theanine ingredient, AlphaWave L-theanine. Among its therapeutic effects, AlphaWave L-theanine was shown to reduce stress and anxiety levels when subjects’ alpha brainwave changes were measured by researchers at the Wellington Sleep Investigation Center at the University of Otago (Wellington, New Zealand), where the study was conducted. Researchers also assessed changes in heart rate as an indication of stress level.
Derived from the leaves of green tea, L-theanine is an amino acid that has been studied extensively for its psychological and stress-reducing benefits. Ethical Naturals says that L-theanine has been shown to block the binding of L-glutamic acid to glutamate receptors in the brain, which inhibited cortical neuron excitation and significantly reduced stress.
In the randomized, double-blind, placebo-controlled study, which is pending publication, the study authors measured alpha brainwaves (via the Karolinska Drowsiness Task) and heart rate levels in 20 human subjects between the ages of 21 and 47 years. Each participant also completed the Brunel Mood Scale (BRUMS) three times over the course of the study to assess vigor, anxiety, and fatigue.
The study took place over the course of two two-hour sessions—an initial screening visit, and a second experimental visit. The participants were split into two groups, with one group supplemented with 200 mg of AlphaWave L-theanine, and the other given an equivalent dose of a placebo. Prior to receiving the dosages, the subjects underwent alpha brainwave testing (by electroencephalography, or EEG) seven times over a 120-minute period. After this test and an additional stress test, subjects were instructed to consume 200 mg of either AlphaWave L-Theanine or the placebo. Over the next 90 minutes, two further stress tests were administered, during which the subjects’ heart rate was measured three times.
The researchers found that the group supplemented with AlphaWave L-theanine experienced significant increases in tonic alpha power (a measure of relaxed wakefulness) compared to the placebo group. Across the board, values for anxiety and tension were low, and decreased over the course of the study for both groups; however, the decrease in the study group was greater. In addition, the AlphaWave group demonstrated significantly less fatigue than did the control group. The study authors also found that supplementation with AlphaWave L-theanine led to reduced heart rate as compared with the placebo group, leading them to conclude that AlphaWave L-theanine is effective in helping to reduce heart rate and increase relaxation, and has the potential to relieve stress.
Of the study results, Cal Bewick, CEO, Ethical Naturals, says: “Many companies now use our AlphaWave L-theanine in their product lines, and I was particularly pleased that this trial gives further support to their use of our brand. These results further confirm the beneficial effects of AlphaWave, and its ability to bring a real sense of relaxation into stressful times.”