Should You Try Theanine For Anxiety?


theanine for anxiety

Green tea contains theanine

Theanine is a compound found in green or black tea, available as a supplement that some people find helpful in relieving their anxiety.

Theanine probably should be considered as a herbal remedy rather than a supplement, since it’s not found naturally in your body.

But like many herbs, it works to boost your body’s functioning in a natural way.


Photo credit: dusky at

Theanine was first discovered when extracted from green tea – but in fact, black tea can contain as much or more theanine as green tea. (Both green tea and black tea come from the same tea bush – Camellia sinensis – but black tea is fermented before it’s dried.)

How does Theanine help anxiety?

If you’re wanting to boost GABA levels in your brain (which will reduce anxiety for many people) then taking theanine might just be the perfect way to do it.

Not only does theanine boost GABA (an inhibitory neurotransmitter), it also tones down some of the stimulating neurotransmitters that make you anxious.

What’s more, it seems to boost brain dopamine – which is one of the “feel good” neurotransmitters – and this might be the reason many people report feelings of well-being and mental focus when they take theanine.

Which is better for anxiety – GABA or Theanine?

GABA is found naturally in your brain, and low levels seem to be related to some types of anxiety. So it makes sense that you would want to increase your GABA levels if you are suffering from anxiety…. and in fact, some people do have great results from taking a straight GABA supplement. Problem is, it doesn’t cross into the brain very easily, so most of the GABA you take might not get to where it’s needed, and it’s hard to regulate your brain levels this way.

On the other hand, Theanine does cross the blood-brain barrier quite well, so it is a sneaky way to boost brain GABA.

Is Theanine an effective remedy for anxiety?

There are no conclusive clinical studies on this. Some people report that it does help relieve their anxiety, while others find it helps them sleep better – and others experience no effect at all.

There are some interesting studies showing that theanine increases alpha wave activity in the brain. Most of these studies were not done with anxiety sufferers….however, people who are prone to anxiety tend to naturally have more beta wave activity, and less alpha; beta waves are associated with alertness, while alpha waves are associated with a more restful, relaxed state.

Another study found that theanine helped to decrease a measured stress response in people put into a stressful experimental situation. (Again, these were not anxiety sufferers – but if you’re prone to anxiety, you probably could do with some help dealing with stress.)

What about a cup of tea?

Drinking tea will certainly give you a boost of theanine. But the amount isn’t standardised and varies widely, from around 5-10 mg for a cup of ordinary tea, to 46 mg in a cup of the highest quality gourmet tea such as matcha or first flush Darjeeling tea.

black tea contains theanine

Black tea contains theanine too!

The crucial difference seems to be not in whether the tea is green or black, but how young the tea leaves are at harvest, since theanine is found in highest concentrations in the buds and young leaves of the tea plant.

Usually these are connoisseur teas, such as matcha, sencha and gyokuro (the most highly valued Japanese green teas). Oolong teas and Darjeeling first flush are other gourmet teas that are likely to be high in theanine, being harvested from young tea leaves.

Photo credit: zirconicusso at

The therapeutic dose of theanine that has been shown to get results ranges between 50-200 mg, so you’re likely to need 5-10 cups of ordinary tea to get the same theanine dose as taking a supplement.

If you want to try a gourmet tea, or just find out more about them, here are two places to explore further:

Like many herbs (and foods) tea may provide extra ingredients that have not yet been identified, but that work with theanine to enhance its effect. One that we do know about is caffeine, which in tea seems to have a positive interaction with theanine and is less likely than coffee to give you the jitters.

Suntheanine, L-theanine, or…

Theanine is chemically an amino acid (though it doesn’t form part of any protein) – and like all amino acids, comes in 2 mirror image shapes: L-theanine and D-theanine. It’s the L-theanine form that is active. D-theanine does nothing at all in your brain.

So it’s L-theanine that you want.

But when theanine is synthesised in the laboratory, the result is a mix of L-theanine and D-theanine, and separating out pure L-theanine adds to the expense of the process. Some manufacturers cut corners, and just use the mixture.

Suntheanine is L-theanine made by the Japanese company Taiyo International. They use a patented process of fermentation that mimics the way that theanine is produced in tea leaves, so it’s as close to naturally produced as you will find. (It’s very expensive to actually extract L-theanine from tea leaves, and none of the commercially available L-theanine is extracted in this way.)

Suntheanine is pharmaceutical grade – over 99% pure – L-theanine.

If you want to be absolutely certain of the purity and quality of the L-theanine you are getting, find a supplement that uses Suntheanine.

That said, L-theanine from other reputable companies may also be pure and high quality. Be careful of the cheaper brands, though, because some of them use a mix of L-theanine and D-theanine, which is less expensive to produce.

Get your mini coaching e-course–
10 Practical Strategies You Can Use To Overcome Anxiety Now
You'll receive the first lesson in your email inbox immediately

Theanine side-effects

Japanese green tea ice-cream

Green tea ice-cream is popular in Japan

Theanine is only just becoming known in Western countries, but in Japan, the land of green tea ice-cream, it’s been approved and used as a supplement and food additive since 1964. The Japanese enjoy theanine in a wide range of food and beverages, including chocolate, soft-drinks, cereals, and herb teas.

They have also studied it extensively in the laboratory, with toxicology and clinical studies. There have not been any reports of adverse effects in almost 50 years of use, or in any of the laboratory studies. The worst thing that seems to happen is that some people report headaches, but that is only with very high doses.

In the USA, L-theanine has been approved by the FDA as a supplement, in doses up to 250 mg, and designated as GRAS (generally recognised as safe).

Photo credit: nuchylee at

As always, please be extra careful if you are pregnant or breast-feeding.

And if you are taking prescribed medication, especially medication for anxiety, then please make sure you discuss it with your doctor or other qualified health practitioner.

The biggest reservation, though, is if you are depressed or prone to episodes of depression – you need to be very cautious about taking anything that increases GABA levels in your brain. Even then, however, theanine seems to be relatively benign and helpful.

Theanine seems to be able to calm your brain without sedating you – in fact, all reports suggest it improves your ability to think clearly. So – unlike most other anti-anxiety medications – it shouldn’t cause any problems with drowsiness.

If you want more details about theanine and the Japanese research into it, you can find a very readable report here.

Should I try theanine for anxiety?

Theanine seems to be one of the most benign and helpful things you could take for anxiety… the worst risk is that it will not help you much or at all.

It probably won’t have as powerful an effect as Xanax – but it is not as risky, either. You will be more likely to be able to function properly without feeling sedated, and you won’t be facing the same risk of  withdrawal or rebound anxiety if you stop taking it.

Start with a dose of 100 mg, and find out for yourself how it affects you. You can double that dose if you think it might help you… some people take even higher doses, but it’s probably best to think of a supplement like theanine as a helper, not a complete anxiety cure.

L-Theanine by Suntheanine

        Jigsaw Health offers 100% pure L-Theanine by Suntheanine which you can buy through this link.





If you would prefer a blended supplement

This supplement by Zen Life  includes L-theanine, GABA, magnesium, B6 and other natural ingredients that have been tested to work together in the most effective proportions to relieve anxiety.

Get your mini coaching e-course–
10 Practical Strategies You Can Use To Overcome Anxiety Now
You'll receive the first lesson in your email inbox immediately


Vanessa (19 Posts)

Vanessa is a healer and practitioner of natural medicine with a background in clinical psychology.

She has a special interest in natural remedies for anxiety, depression, and other dysfunctions that keep us from living a full and joyful life.