Theanine and caffeine are both found naturally in tea (Camellia sinensis) and have been suggested to improve brain function, alertness, and attention.
Theanine is non-protein forming amino acid that is similar to glutamic acid and caffeine is a natural plant alkaloid.
A large amount of research has been done using theanine and caffeine, however, very little has been done to test this combination in a clinical trial. Theanine alone has 400 research articles on PubMed.
A recent study published in the journal Nutrition Research tested a combination of theanine and caffeine to improve brain function, alertness, and decrease responses to distractions.
Here are the study details
– A randomized placebo controlled crossover design was used.
– Nine adult men (age 18-60 years)
– The study was conducted over 5 weeks with weekly visits
– Dose: At each clinic visit 200 mg of L-theanine and 160 mg of caffeine were administered.
– Powder of theanine and caffeine was mixed in 200 milliliters of water. The mixture was drank in 1 minute.
– 60 minutes after administration a 20 minute functional MRI (magnetic resonance imaging) was performed with a visual color stimulus test.
Here are the results
– L-Theanine resulted in faster responses to targets compared with placebo (∆ = 27.8 milliseconds, P = .018).
– Here are more clinical trials using tea for health promotion.
– Theanine–caffeine combination resulted in faster responses to targets compared with placebo (∆ = 26.7 milliseconds, P = .037, respectively).
– l-Theanine was associated with decreased fMRI responses to distractor stimuli in brain regions that regulate visual attention, suggesting that l-theanine may be decreasing neural resource allocation to process distractors, thus allowing to attend to targets more efficiently.
– l-Theanine–caffeine combination was associated with decreased fMRI responses to target stimuli as compared with distractors in several brain regions that typically show increased activation during mind wandering.
Here is what the authors had to say
We found significantly faster reaction times to the target stimuli with l-theanine and l-theanine–caffeine combination compared with the placebo.
and
Therefore, our study provides preliminary evidence to suggest that oral consumption of 200 mg of l-theanine alone or in combination with 160 mg of caffeine may improve performance in tasks that require stimulus discrimination.
Take away message
The dose of theanine used in this study was 200 mg. This amount of theanine is equivalent to about 8 cups of tea or many commercially available supplements. The dose of 160 mg of caffeine is equivalent to about 8 cups of tea or 1 ½ cups of coffee. Here are more clinical trials related to brain function and natural ingredients inlcuding lavendar for migraines, ginkgo, valerian and grape juice are here.
The results of this study suggest that a combination of theanine and caffeine may help improve brain function while decreasing responses to distractions. This study is small but it does complement a significant amount of research that suggests L-theanine can improve brain function.
Reference
Kahathuduwa e t al. l-Theanine and caffeine improve target-specific attention to visual stimuli by decreasing mind wandering: a human functional magnetic resonance imaging study. Nutrition Research. Volume 49, January 2018, Pages 67-78
His research on plant medicine has led to more than 45 publications and abstracts.This research has been presented at international meetings in the USA, France, Turkey, Peru, Israel, Austria, and Italy.
Categories: Brain, Clinical Trials, Dietary Supplements, Mental Health, Mood