L-theanine is an amino acid found in tea leaves. Previous studies of dietary L-theanine supplements have suggested a therapeutic benefit in reducing stress, promoting relaxation and improving the quality of sleep. Akiko Higashiyama of the University of Shiga Prefecture in Japan and colleagues found that taking 200 milligrams per day of L-theanine helps people with anxiety focus on their daily activities.
The researchers recruited 18 healthy university students and assessed their anxiety levels using a standardized rating scale. Students with high anxiety were put in one group, while students with minimal anxiety were put in another group. Both groups received water or water plus 200 milligrams of L-theanine per 100 milliliters of water. The test was performed repeatedly, and assessments were done between 15 and 60 minutes after the subjects took the supplement.
The results showed that highly anxious students getting the L-theanine experienced a slowing of their heart rate, improved attentional performance and better reaction times compared to the highly anxious students who got a placebo. The students with minimal anxiety did not appear to get significant benefits. “The results demonstrate the significant enhanced activity of alpha bands, descending heart rate, elevated visual attentional performance and improved reaction time response among high-anxiety-propensity subjects compared to a placebo,” the researchers wrote. “Results evidently demonstrated that L-theanine clearly has a pronounced effect on attention performance and reaction time response in normal healthy subjects prone to have high anxiety.”
Higashiyama, et al. (2011). Effects of L-theanine on attention and reaction time response. Journal of Functional Foods. April 19.
—Dr. Bob Goldman
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Dr. Robert M. Goldman MD, PhD, DO, FAASP has spearheaded the development of numerous international medical organizations and corporations. Dr. Goldman has served as a Senior Fellow at the Lincoln Filene Center, Tufts University; as an Affiliate at the Philosophy of Education Research Center, Graduate School of Education, Harvard University, He is Clinical Consultant, Department of Obstetrics and Gynecology, Korea Medical University; and Professor, Department of Internal Medicine at the University of Central America Health Sciences, Department of Internal Medicine. Dr. Goldman holds the positions of Visiting Professor, Udayana University School of Medicine, Indonesia; Visiting Professor, Huazhong University of Science & Technology Tong Ji Medical School, China; Visiting Professor, The Wuhan Institute of Science & Technology, China; Visiting Professor at Hainan Medical College, China; and Visiting Professor, School of Anti-Aging, Aesthetics and Regenerative Medicine, UCSI University, Malaysia. Dr. Goldman is a Fellow of the American Academy of Sports Physicians and a Board Diplomat in Sports Medicine and Board Certified in Anti-Aging Medicine. Dr. Goldman is a Fellow of the American Academy of Sports Physicians and a Board Diplomat in Sports Medicine and Board Certified in Anti-Aging Medicine. He has overseen cooperative research agreement development programs in conjunction with such prominent institutions as the American National Red Cross, the US National Aeronautics and Space Administration (NASA), the Department of Defense, and the FDA’s Center for Devices & Radiological Health.
Dr Goldman was awarded the 2012 LifeTime Achievement Award in Medicine &Science. Dr. Goldman is the recipient of the ‘Gold Medal for Science, the Grand Prize for Medicine, the Humanitarian Award, and the Business Development Award. He received honors from Minister of Sports and government Health officials of numerous nations. In 2001, Excellency Juan Antonio Samaranch awarded Dr. Goldman the International Olympic Committee Tribute Diploma for contributions to the development of sport & Olympism.
In addition, Dr. Goldman is a black belt in karate, Chinese weapons expert, and world champion athlete with over 20 world strength records, he has been listed in the Guinness Book of World Records. Some of his past performance records include 13,500 consecutive situps and 321 consecutive handstand pushups. Dr. Goldman was an All-College athlete in four sports, a three time winner of the John F. Kennedy (JFK) Physical Fitness Award, was voted Athlete of the Year, was the recipient of the Champions Award, and was inducted into the World Hall of Fame of Physical Fitness. Dr. Goldman was awarded the Healthy American Fitness Leader Award from the President’s Council on Physical Fitness & Sports and U.S. Chamber of Commerce. Dr. Goldman is Chairman of the International Medical Commission overseeing sports medicine committees in over 184 nations. He has served as a Special Advisor to the President’s Council on Physical Fitness & Sports. He is founder and international President Emeritis of the National Academy of Sports Medicine and the cofounder and Chairman of the American Academy of Anti-Aging Medicine (A4M). Dr. Goldman visits an average of 20 countries annually to promote brain research and sports medicine programs.