How to Use L-Theanine For Better Sleep

L-theanine is a common ingredient in various sleep formulations you’ll find around the internet. But what is it exactly, how does it benefit sleep and most importantly - does it work (and have scientific studies backing it?) Let’s dive in.

TLDR: L-Theanine for Sleep

  • Dose: Take 150-200mg of L-theanien
  • Timing: Take 30 minutes before bed-time
  • Mechanism of Action: L-theanine promotes alpha-wave activity
  • Safety profile: Very safe
  • Recommended product: Impossible Sleep 

What Is L-Theanine?

We cover l-theanine in depth in our IMPOSSIBLE guide to l-theanine, but at it’s basic level, l-theanine is an amino acid that is typically not found in most diets. However, l-theanine is very common in teas and is known to have a profound effect on the brain and yes - even effects your sleep.

The Molecular Makeup of L-Theanine

l-theanine-molecular-makeup

The Benefits of L-Theanine for Sleep

L-theanine is known to be included in several day time drinks to take the “edge off” caffeine drinks and other stimulants, but that’s not the best way to use it. In some cases - that can actually interfere with your sleep later on in the day.

We recommend using l-theanine primarily for sleep., This is because it has powerful properties that can help you have a restful night including:

  • Improved relaxation within 30-60 minutes
  • Small reduction in anxiety
  • Small improvements in sleep quality (especially for high energy individuals)
  • Large decrease in overall stress
  • Decreases in severity of insomnia (again with individuals with especially high energy)

Because of the timing required with l-theanine, you should typically take your nightly dose about 30 minutes before you head off to sleep.

L-Theanine Sleep Dosage: How Much L-Theanine Should You Take For Sleep?

Many sleep supplements contain trace amounts of l-theanine (20-50mg). While, it’s nice of those supplements to have it in their ingredient list, those doses aren’t backed by any studies and it’s likely not enough to actually help you get to sleep.

Typically, the recommended doses for l-theanine are between 100-200mg. It’s typically recommended to limit the upper limit consumption of l-theanine to 350mg/day.

Because l-theanine can be bitter, too much can make for a sour tasting dose and active other senses that may make it harder to sleep.

For that reason - we typically recommend 150-200mg of l-theanine per night as the ‘sweet spot’ for the purposes of sleep.

L Theanine & Magnesium for Sleep

L-theanine is known to promote relaxation and decrease anxiety as mentioned above, but it doesn’t necessarily help you recover as an athlete.

In other words, it’s worth thinking about l-theanine as helping you “dim the lights” or “turn off your brain” - which is a common issue for elite athletes and high performers around the world.

This is where magnesium comes in.

Magnesium is one of the most effective (and natural) supplements you can take for sleep. You can read our full guide to magnesium and sleep here, but it promotes deep sleep and full body recovery.

When you combine l-theanine and magnesium - you get the best of both worlds. A gentle wind down at the end of the night and deep sleep and strong recovery so you can wake up well rested and recovered.

L-Theanine's Mechanism of Action

L-theanine is an amino acid that can cross the blood-brain barrier and reach your brain.

There, it promotes alpha-wave activity - the calming brain activity usually associate with "flow state."

This calming feeling is typically useful for high performers and type A people that have a hard time "winding down" for the evening.

It's important to note that there are no studies that l-theanine actually improves your sleep once you are asleep - but it's a very key ingredient to getting you to sleep.

So, instead of staring at the ceiling all night, you can make a nice cup of tea, wind down for the evening and turn your brain off - sometimes the hardest part of sleep.

Side note: The calming effect of l-theanine is sometimes why it's used to offset the "jittery" effects of caffeine (by taking the two together) - but obviously we don't recommend taking caffeine before bedtime.

Side effects of L Theanine

Because l-theanine is an amino acid, it has a relatively safe side effect profile. There are no known side effects or toxicity known because of high dosages.

However, due to the calming nature of the compound, it may reduce blood pressure - an undesired effect if you have chronically low blood pressure already or are on prescription medication to keep blood pressure high.

Primary side effects of l-theanine

  • relatively safe side effect profile
  • should be avoided if you're on prescription low blood sugar medication

L-Theanine in The Media

Andrew Huberman recommends l-theanine and magnesium in his sleep cocktail here.

We’ll add more media references to l-theanine as they drop, but we expect them to grow as l-theanine’s use in sleep products is becoming very popular.

Other Citations on L Theanine & Sleep

Other Sleep Related Articles

If you’re looking to optimize your sleep - check out these other articles all about recovery at your optimal level.


Photo by Lux Graves

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