Australian Researchers Use Brain Imaging to Test Effects of Anti-Stress L-Theanine Beverage

Photo from Neuro Bliss

New preliminary clinical results indicate that Neuro Bliss, a functional beverage marketed for relaxation, may help reduce stress levels in human subjects. Researchers from Australia’s Swinburne University of Technology’s Center for Human Psychopharmacology recently presented data from the 34-subject, randomized, double-blind, placebo-controlled crossover study at the Association for Psychological Sciences Conference.

In addition to testing subjects with Multitasking Framework Assessment, comprising a battery of cognitive exercises, the researchers used magnetoencephalography (MEG) analysis to measure brain activity. With MEG, scientists are able to measure magnetic activity in specific areas of the brain. The Swinburne University researchers claim that this is the first time MEG has been used to measure the effects of a natural ingredient in a functional beverage.

Unlike more commonly used electroencephalogram (EEG) analysis, “MEG records the corresponding magnetic field without the smearing effect of conduction through the skull, which limits the spatial resolution of EEG,” according to Neuro Bliss representatives.

The crossover trial took place over the course of two days. Each day, subjects consumed either a placebo or one bottle of the Neuro Bliss drink containing 200 mg of L-theanine, a relaxation-inducing amino acid found in green tea. Researchers measured stress, cortisol levels, and other cognitive functions one hour post-intervention.

According to Neuro Bliss, one hour post-treatment subjects self-reported experiencing lower levels of stress in response to the Multitasking Framework Assessment testing. Researchers also measured subjects’ salivary cortisol levels and did find initially significant differences (lower levels in the treatment group) three hours post-ingestion, but significance began to diminish one hour after product ingestion. Cortisol is the primary hormone the body releases during times of stress.

MEG testing showed some evidence that alpha wave activity increased in the Neuro Bliss subjects. Higher alpha wave activity is generally linked to a more relaxed mental state. According to researchers, MEG analysis showed “non-significant trends suggesting both a phasic and tonic shift towards increased alpha.”

In addition to the relaxation-inducing L-theanine (supplier Blue California’s L-TeaActive branded ingredient), Neuro Bliss includes brain-health ingredient phosphatidylserine (Chemi Nutra’s SerinAid brand), vitamin D3, and chamomile.

Neuro Bliss is now submitting this study for publication. NeuroBrands as well as Blue California funded the study.

Swinburne University researchers have investigated the effects of other relaxation-inducing herbal ingredients, including a 2013 study published in Phytotherapy Research looking at the effects of the herbal Bacopa monnieri on cognition, mood, and cortisol.

Jennifer Grebow
Editor-in-Chief
Nutritional Outlook magazine
jennifer.grebow@ubm.com