New Study Shows That L-Theanine May Counter The Effect Of Late-Night Caffeine
Caffeine is often used to help us power through our days and sometimes (regrettably) nights. And tea is one of the most popularly consumed, and naturally caffeinated, drinks worldwide. Green tea also contains a calming compound that helps counter caffeine’s jitteriness: L-theanine.*
Here’s what you need to know.
The study’s setup
Researchers created four different beverages for each of the participants to try: one with 50 milligrams of L-theanine, one with 30 milligrams of caffeine, one with both, and a placebo.
Each person consumed each beverage once and then waited a week before continuing with the next. And here’s the kicker, they consumed it 10:50 pm—10 minutes before going to bed.
They had electrodes attached to the scalp to measure sleep stage and brain wave activity and underwent brain imaging each night of the study (four total).
What the results showed
After all this, there was one sign that L-theanine may combat some of caffeine's detriment on sleep. Specifically, drinking the caffeine and L-theanine beverage significantly reduced the total number of minutes people spent awake after initially falling asleep compared to just the caffeine.
Even compared to the placebo and L-theanine drinks alone, the combined one was linked to the least amount of wakefulness minutes (although these comparisons were not statistically significant and could have happened by chance).
Other measures of sleep (like total time asleep, time it took to fall asleep, etc.) were not significant between any of the groups.
What does this mean for you?
While these are interesting findings, there are not a lot of conclusions that can be drawn from this alone. It was a small, short study, and most people likely aren’t choosing to consume caffeine minutes before going to bed.
But putting these findings in the context of what we already know about L-theanine can help you time out when you should ingest these compounds for optimal productivity and sleep.
Caffeine is also best consumed earlier, and most experts recommend having a strict cutoff time for caffeine—approximately six hours before you go to bed.
Sustained and focused energy
focus+ offers premium sourcing and quality of ingredients at their full-potency, clinically researched doses—including 100 milligrams of L-theanine (as Suntheanine®) in addition to 150 milligrams of instant- and sustained-release caffeine from antioxidant-rich botanicals.
While focus+ can be taken any time of day, the same at least six hours before bed guideline, applies due to the caffeine content.
Optimizing sleep and caffeine intake is top of mind in today’s hectic world. And while it’s well established that caffeine is stimulatory and L-theanine is calming, the degree to which L-theanine by counter caffeine’s energizing impact is not clear.*
While researchers continue to parse out that question, it’s still best to take in green tea or supplement with these ingredients long before you hit the hay.
Molly Knudsen, M.S., RDN is a Registered Dietician Nutritionist and mindbodygreen's supplements editor. She holds a bachelor’s degree in nutrition from Texas Christian University and a master’s in nutrition interventions, communication, and behavior change from Tufts University. She lives in Boston, Massachusetts and enjoys connecting people to the food they eat and how it influences health and wellbeing.