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SALE NOW ON + Extra £5 Off Discount Code: JVB18    Min Order £25, Ends Midnight 6th March

High Strength L-Theanine Capsules - 400mg

UK's strongest L-Theanine - Pure & potent double-strength capsules

(25 reviews)9410020
Buy High Strength L-Theanine Capsules - 400mg
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  • Double-strength capsules
  • Purest form available
  • Strongest form available in the UK
  • Increases brain alpha waves

Supplement Description

Introducing our new double-strength L-Theanine capsules. L-Theanine supports a sense of calm, contentment and well-being. It crosses the blood brain barrier and has been shown to increase brain alpha waves in less than 40 minutes. Alpha brain waves are an indication of a state of relaxation and mental alertness similar to that achieved through meditation, this promotes a feeling of relaxation but with an alert state of mind.

Theanine is an amino acid found predominantly in tea.  When you have a stressful moment or a shock a 'cup of tea' one of the first things that come to mind but why? The reason is thought to be L-Theanine which is believed to be responsible for the calming and relaxing effect of a cup of tea.

If you are a coffee drinker it's likely that at some point you will have drunk too much and experienced a 'hyper' effect.  It is very doubtful that you have ever experienced the same thing with tea even though it contains a lot of caffeine and the reason why is thought to be theanine. It is also a supplement which is not known to be addictive.

Purest form available, strong and high grade material

A single capsule provides 400mg of this high-grade amino acid in a vegetarian capsule - currently the strongest form available in the UK.

Nutritional Information

Each capsule typically provides:
L-Theanine 400mg

Allergen Advice

Any allergens are highlighted in bold in the ingredients list.

List of Ingredients

L-Theanine, Hydroxypropylmethyl Cellulose, Maltodextrin, Silicon Dioxide.

Suitable for vegetarian and vegan diets.

Dosage / Suggested Intake

Swallow one capsule per day with food, or as directed by your health professional.

Capsule Size

23mm x 8mm Oblong capsule

Legal Category

Food Supplement

Customer Reviews for High Strength L-Theanine 400mg

The views expressed below are the personal opinion of Just Vitamins customers. Just Vitamins does not endorse these views, nor should they be regarded as health claims or medical advice. All reviews are collected and verified as genuine by a 3rd party called Feefo.

Overall product rating 9.4 / 10 - 25 customers have independently reviewed and recommend High Strength L-Theanine from 25 reviews
Review Date
Review Details
Service Rating: Never any problems and products are good
Product: A calming supplement instead of taking addictive medicine
It took 10 days to arrive not 5. Not waiting that long again I’m afraid. I can have stuff from the other side of the world in half that.
Feedback Response: Thank you for your feedback

We dispatch all orders (including yours) within 24 hours of receipt, but unfortunately we are at the mercy of the local postal service once it leaves us.  We do offer additional postage methods to guarantee a faster delivery.
Service Rating: First class service from start to finish, products as described and prices are hard to beat, delivered in time too.
Product: Quality is as expected. Great product.
Service Rating: Fast delivery, excellent packaging of product and delivery package (cardboard). The discount details were relayed to me quickly by support when I wrote to them. Regular updates on status of my order.
Product: Excellent and does what it says on the label. Keeps me calm and relaxed.
Service Rating: I ordered L-Theanine from Just Vitamins which are recommended for helping to reduce the symptoms of stress. I found the website easy to navigate and the capsules arrived promptly. I feel the capsules are definitely helping and will be re-ordering when I need more. Thank you.
Product: I take one capsule daily and I personally feel an improvement in my stress levels. I will buy this product again.
Great Service
Service Rating: Good.
Product: Its not effective. I was getting more benefit from green tea.
Feedback Response: Hi,
Sorry you feel this supplement is not effective for you yet, but please persevere - it may take up to 3 months for you to recognise the benefits.
Kind regards,
Just Vitamins Customer Team
Glad to be able to get hold of L-Theanine for supplementary treatment of epilepsy.
Always excellent, prompt service and good communication. Recommended.
Service Rating: Always a. 5 star service that's why I keep coming back
Product: Great supplement.I take this on regular basis and you provide capsules with the highest strenght.
Delighted with service & product will be using just vitamins again
Service Rating: Great service fast deliveey
Product: Always A* service.Speedy delivery and great communication.
Service Rating: Excellent service and very keen prices
Product: Excellent products at very keen prices!
Service Rating: responded really quickly to my enquiry. packages fit through the letterbox which is great. very pleased, will purchase again.
Product: good value for money, pleased with the product.
Service Rating: As usual, excellent service from Just Vitamins. Good price, rapid delivery.
Product: good to have double strength available. Helps with my SADs
Service Rating: Good service, delivered on time as promised.
Product: Great product, eases the nerve pain in my fingers.
Service Rating: Quick service and good product. I have ordered several times and never had any issues.
Product: I find L-theanine a very effective product
Service Rating: Good product at reasonable price
Product: Good product at a resanabel price
Service Rating: Great service delivered fast in nice flat packs that fit though the letterbox
Product: Great Product seem to be working well for me
Service Rating: Just love how quick delivery is and i dont have to wait in!
Product: Really helps my brain fog. I am amazed at how qickly this works
Service Rating: Great company prompt service would use again.🤓🤓🤓🤓🤓
Product: Still taking hopefully will be as good as any others
Service Rating: Really quick service, no problems.
Product: Seem to do the job,going to send for some more after Christmas
Brilliant Products and very fast service! :)
Service Rating: Schnelle Lieferung, guter Preis, bin 100% zufrieden
Product: Bin wunderbar entspannt und zufrieden