Ingredient Spotlight — L-Theanine (Suntheanine®) · PM Formula

Calm, on Cue

Relaxation is easy to claim and hard to prove. So researchers stressed people on purpose, then measured two things you can't fake — brainwaves and cortisol — after a single dose of L-theanine.

Everyone sells "calm." Almost no one shows it happening. The interesting version of this ingredient isn't a mood you report on a survey — it's a shift you can see on an EEG and in a saliva sample, on demand, when the pressure is actually on. This trial engineered exactly that test.

The trial

In a randomized, triple-blind, placebo-controlled crossover study, healthy, moderately stressed adults took a single 200 mg dose of L-theanine or placebo. Stress was induced with a timed mental-arithmetic challenge, and researchers measured EEG alpha-wave activity, salivary cortisol, blood pressure, heart rate, and self-reported stress.

What they found

• More alpha power — the relaxation signature. L-theanine produced a greater increase in frontal and whole-scalp alpha activity versus placebo (p ≤ 0.050), the brainwave pattern linked to a calm, settled state.
• Lower cortisol, fast. Salivary cortisol dropped more with L-theanine than placebo just one hour post-dose (p < 0.001).
• Safe and well tolerated. No safety concerns were reported.

The authors concluded a single dose of L-theanine "significantly increased frontal region alpha power in response to an acute stress challenge," changes "indicative of relaxation in the brain."

Calm you can measure — in brainwaves and in cortisol — within an hour of a single dose.

Why it's in the PM formula

The evening job is to bring the day's stress down so rest can begin — and this is the mechanism, measured: more alpha, less cortisol, quickly. We formulate with Suntheanine® L-theanine (the same 200 mg dose studied here, in a different branded material), paired with PharmaGABA®, precisely because that alpha-up, cortisol-down shift is the physiology of a real wind-down.

Reference: Evans M, McDonald AC, Xiong L, Crowley DC, Guthrie N. A Randomized, Triple-Blind, Placebo-Controlled, Crossover Study to Investigate the Efficacy of a Single Dose of AlphaWave® L-Theanine on Stress in a Healthy Adult Population. Neurology and Therapy. 2021;10(2):1061–1078. doi:10.1007/s40120-021-00284-x.
Read it: pubmed.ncbi.nlm.nih.gov/34562208

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.