.media-gallery--loading { visibility: visible; } .media-gallery--loading::before { display: none; } .media-gallery__slider--loading { position: relative; }

l theanine supplement gaba supplement uk l theanine capsules

l-theanine-supplement-theaninebenefits-theanine-side-effects

ltheanine-supplement-theanine-benefits-buy-theanine

l theanine supplements l theanine benefits

l theanine supplement ltheanine gaba supplement

natural anxiety relief anxiety supplement l theanine benefits

l theanine supplement l theanine benefits anxiety supplement

Natural L-theanine

Name: Natural L-theanine
Rating: 4.2 (132 reviews)

Regular price £14.99

Tax included

Size

30 capsules

60 capsules

Quantity

Purchase Options

Delivery Frequency

- -

View subscription policy

as seen in

planet organic (1).png__PID:df3fcb8f-49fb-45c0-9f70-4c893e77700f

wholefoods (1).png__PID:3e77700f-ac9b-40da-9bbb-485086381e36

Feel calm and composed with our natural 250mg l-theanine capsules. Theanine is a natural nutrient found in green tea which promotes relaxation without sedation [1]. Our fast-acting, non-sedative l theanine supplement delivers the equivalent theanine content of 15-20 cups of green tea in a single dose.

1-a-day. Single capsule dose
Ideal for anybody looking to unwind, relax but maintain mental clarity or anyone facing acute stressors such as public speaking or travelling
Increases the relative concentrations of your relaxation chemical GABA within 30 minutes of ingestion [2,3]
250mg natural L-theanine powder per capsule

Our l-theanine supplement is manufactured in the UK under strict GMP, ISO 9001, and ISO 22000 certified conditions in an FDA-registered facility.

66 studies show l-theanine promotes relaxation

brain feed’s analysis of 66 published trials confirmed that l-theanine supports relaxation. Backed by science, proven by research.

Theanine (1).jpg__PID:ac08d069-10d1-4b73-9ff4-442e4f0f00a6

lTheanine-supplements.jpg__PID:382b3f33-a92d-46aa-a3b9-d64a941c1cb6

*brain feed does not test or commission studies on animals. This is an analysis of pre-existing studies.

what is l-theanine ?

l-theanine-green-tea-supplement-l-theanine-benefits.jpg__PID:24ce3384-fe4a-4a72-aabc-4f6c483f87c5

Responsible for green tea’s calming effects, theanine is a naturally occurring amino acid. It’s found primarily in green tea with small amounts also present in black tea and some food sources [4]. Theanine supplements provide a concentrated theanine dosage free from the additional compounds found in green tea.

l theanine supplement l theanine benefits theanine dosage

natural l theanine supplements natural anxiety relief anxiety supplement

Many L-theanine supplements use a synthetic form of theanine known as Suntheanine which is made through a chemical process involving ethylamine and L-glutamine. Our theanine is manufactured using a natural fermentation process involving non-GMO corn.

l-theanine benefits

relaxation

Theanine easily crosses the blood-brain barrier and increases the relative concentrations of your relaxation chemical GABA within 30 minutes of ingestion [2,3]. The effects last around 90 minutes [5].

calming supplement l theanine benefits l theanine capsules

l theanine supplements l theanine and lemon balm calming supplements

mental clarity

Human studies show that theanine increases alpha brain waves, which signify a relaxed yet alert state [6]. This type of brain wave activity enhances creativity, improves performance under stress, and reduces anxiety [7].

Compared to conventional calming supplements, l-theanine does not cause drowsiness, slowed reflexes, or impaired concentration [8].

track your progress

Track how theanine works for you over time. Adapted from research methods used in over 20 clinical trials across 15 years, brain feed’s user-friendly self-assessments deliver near-instant results. Monitor your brain health through a simple 3-step process, included with your first theanine order, to track results at baseline, 1 day, and 30 days.

supplement-test-dopamine-test (1).jpg__PID:97590955-b531-4b1d-9940-bc6d514a78a6

what is GABA ?

GABA is a neurotransmitter that helps balance and calm neural activity. By modulating brain activity, GABA benefits your wellbeing by contributing to a sense of inner peace and promoting feelings of calmness [9]

how to increase GABA naturally ?

what does gaba do how to increase gaba supplements

Increasing GABA levels in the brain can be achieved by :

Vigorous exercise – 8-17 minutes of vigorous exercise was shown to increase GABA levels [10].
Yoga – practising yoga for 60 minutes a day 3 times a week for 12 weeks was shown to increase GABA levels [11].

While GABA supplements are available, they can’t be sold in the UK or Canada. The effectiveness of these supplements are still debated.

Early research suggested that GABA was unable to enter the brain [12,13] theorised due to its polar nature, which blocks it from crossing the blood-brain barrier [13]. Newer studies indicate that while GABA might enter the brain in small amounts [12], it is quickly removed. In mice, the rate at which GABA leaves the brain is 17 times higher than the rate at which it enters [14], which might explain the limited evidence of GABA crossing the blood-brain barrier.

Theanine reliably crosses the blood-brain barrier [15] offering a well-studied, safe and effective relaxation supplement.

natural stress relief stress supplement anxiety supplement gaba uk

1. Mason, R. (2001). 200 mg of Zen: L-Theanine Boosts Alpha Waves, Promotes Alert Relaxation. Alternative and Complementary Therapies, 7(2), 91–95. https://www.liebertpub.com/doi/10.1089/10762800151125092

2. Nobre, A. C., Rao, A., & Owen, G. N. (2008). L-theanine, a natural constituent in tea, and its effect on mental state. Asia Pacific Journal of Clinical Nutrition, 17(S1), 167–168. https://www.airitilibrary.com/Article/Detail/09647058-200801-201306140008-201306140008-167-168

3. Chen, S., Kang, J., Zhu, H., Wang, K., Han, Z., Wang, L., Liu, J., Wu, Y., He, P., Tu, Y., & Li, B. (2023). L-Theanine and Immunity: A Review. Molecules, 28(9), 3846. https://www.mdpi.com/1420-3049/28/9/3846

4. Eschenauer, G., & Sweet, B. V. (2006). Pharmacology and therapeutic uses of theanine. American Journal of Health-System Pharmacy, 63(1), 26–30. https://academic.oup.com/ajhp/article-abstract/63/1/26/5134445?redirectedFrom=fulltext

5. Higashiyama, A., Htay, H. H., Ozeki, M., Juneja, L. R., & Kapoor, M. P. (2011). Effects of l-theanine on attention and reaction time response. Journal of Functional Foods, 3(3), 171–178. https://www.sciencedirect.com/science/article/pii/S1756464611000351?via%3Dihub

6. Micallef, J., Soubrouillard, C., Guet, F., Le Guern, M. E., Alquier, C., Bruguerolle, B., & Blin, O. (2001). A double blind parallel group placebo controlled comparison of sedative and amnesic effects of etifoxine and lorazepam in healthy subjects. Fundamental and Clinical Pharmacology, 15(3), 209–216. https://onlinelibrary.wiley.com/doi/10.1046/j.1472-8206.2001.00025.x

7. Rao, T. P., Ozeki, M., & Juneja, L. R. (2015). In Search of a Safe Natural Sleep Aid. Journal of the American College of Nutrition, 34(5), 436–447. https://www.tandfonline.com/doi/full/10.1080/07315724.2014.926153

8. Song, C. H., Jung, J. H., Oh, J. S., & Kim, K. S. (2016). Effects of Theanine on the Release of Brain Alpha Wave in Adult Males. Korean Journal of Nutrition, 36(9), 918–923. https://www.koreamed.org/SearchBasic.php?RID=0124KJN/2003.36.9.918&DT=1

9. Juneja, L. R., Chu, D.-C., Okubo, T., Nagato, Y., & Yokogoshi, H. (1999). L-theanine-a unique amino acid of green tea and its relaxation effect in humans. Trends in Food Science & Technology, 10(6), 199–204.https://www.sciencedirect.com/science/article/abs/pii/S0924224499000448?via%3Dihub

10. Maddock, R. J., Casazza, G. A., Fernandez, D. H., & Maddock, M. I. (2016). Acute Modulation of Cortical Glutamate and GABA Content by Physical Activity. The Journal of Neuroscience, 36(8), 2449–2457. https://www.jneurosci.org/content/36/8/2449

11. Krishnakumar, D., Hamblin, M. R., & Lakshmanan, S. (2015). Meditation and Yoga can Modulate Brain Mechanisms that affect Behavior and Anxiety-A Modern Scientific Perspective. Ancient Science, 2(1), 13–19. http://vripress.com/index.php/AS/article/view/171

12. Boonstra, E., de Kleijn, R., Colzato, L. S., Alkemade, A., Forstmann, B. U., & Nieuwenhuis, S. (2015). Neurotransmitters as food supplements: the effects of GABA on brain and behavior. Frontiers in psychology, 6, 1520. https://www.frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2015.01520/full

13. Knudsen, G. M., Poulsen, H. E., & Paulson, O. B. (1988). Blood-brain barrier permeability in galactosamine-induced hepatic encephalopathy. No evidence for increased GABA-transport. Journal of hepatology, 6(2), 187–192. https://www.journal-of-hepatology.eu/article/S0168-8278(88)80030-8/abstract

14. Kakee, A., Takanaga, H., Terasaki, T., Naito, M., Tsuruo, T., & Sugiyama, Y. (2001). Efflux of a suppressive neurotransmitter, GABA, across the blood–brain barrier. Journal of Neurochemistry, 79(1), 110–118. https://onlinelibrary.wiley.com/doi/epdf/10.1046/j.1471-4159.2001.00540.x

15. Lardner A. L. (2014). Neurobiological effects of the green tea constituent theanine and its potential role in the treatment of psychiatric and neurodegenerative disorders. Nutritional neuroscience, 17(4), 145–155. https://www.tandfonline.com/doi/full/10.1179/1476830513Y.0000000079

16.Rao, T. P., Ozeki, M., & Juneja, L. R. (2015). In Search of a Safe Natural Sleep Aid. Journal of the American College of Nutrition, 34(5), 436–447. https://www.tandfonline.com/doi/full/10.1080/07315724.2014.926153

17.Lu, K., Gray, M. A., Oliver, C., Liley, D. T., Harrison, B. J., Bartholomeusz, C. F., Phan, K. L., & Nathan, P. J. (2004). The acute effects of L-theanine in comparison with alprazolam on anticipatory anxiety in humans. Human Psychopharmacology: Clinical and Experimental, 19(7), 457–465. https://onlinelibrary.wiley.com/doi/10.1002/hup.611

18.Yokogoshi, H., Kobayashi, M., Mochizuki, M., & Terashima, T. (1998). Effect of Theanine, r-Glutamylethylamide, on Brain Monoamines and Striatal Dopamine Release in Conscious Rats. Neurochemical Research, 23(5), 667–673. https://link.springer.com/article/10.1023/A:1022490806093

19 Borzelleca, J. F., Peters, D., & Hall, W. (2006). A 13-week dietary toxicity and toxicokinetic study with l-theanine in rats. Food and Chemical Toxicology, 44(7), 1158–1166. https://www.sciencedirect.com/science/article/abs/pii/S0278691506000949?via%3Dihub

20. Navarro, V. J., Khan, I., Björnsson, E., Seeff, L. B., Serrano, J., & Hoofnagle, J. H. (2017). Liver injury from herbal and dietary supplements. Hepatology, 65(1), 363–373. https://journals.lww.com/hep/fulltext/2017/01000/liver_injury_from_herbal_and_dietary_supplements.36.aspx

21. Unno, T., Suzuki, Y., Kakuda, T., Hayakawa, T., & Tsuge, H. (1999). Metabolism of Theanine, γ-Glutamylethylamide, in Rats. Journal of Agricultural and Food Chemistry, 47(4), 1593–1596. https://pubs.acs.org/doi/10.1021/jf981113t

purity promise ™

Purity Promise™

Purity has four components:

1. brain feed ensures the high quality of our extracts and isolates through rigorous testing
2. We monitor critical control points during production for quality control
3. We guarantee the amount of active ingredient(s)
4.Preserve the bio-active compounds for the duration of their shelflife.

Click here to read more

NutriProtect ™

NutriProtect™

Nutriprotect™ is our innovative capsule technology with additional UV protection built into the shell. It improves nutrient stability, allowing us to remove a permanent UV barrier used in composite packaging materials. The net result: fully recyclable pouches. Click here to read more.

FAQ's

Is this natural theanine ?

+ -

Theanine is the major amino acid in green tea. Our theanine is manufactured using a natural fermentation process involving non-GMO corn.Many L-theanine supplements use a synthetic form of theanine known as Suntheanine which is made through a chemical process

How to take theanine ?

+ -

1 l theanine capsule with a glass of water. Max 2 per day.

Are there any l theanine side effects or contraindications ?

+ -

Anybody taking medication for high blood pressure should consult their GP. If you have low blood pressure, discuss theanine with your healthcare provider before starting it.

What should I notice?

+ -

Relaxation without sedation.Oral administration of 200mg of theanine in men aged 20-25 years old also resulted in a reduction in the heart rate. [16]

Does theanine benefit cognition ?

+ -

In human studies, theanine alone has shown virtually no positive effects on performance. However, 250mg of theanine has been found to positively interact with caffeine to enhance reaction time, the accuracy of rapid information processing, mental fatigue and tiredness. [21] This combination also enhanced the speed of rapid information processing, sentence verification and word recognition reaction time when caffeine alone did not. [20]

Can I just drink a lot of green tea to get enough theanine?

+ -

To obtain sufficient levels of theanine for a therapeutic dose from whole green tea powder would also result in high levels of caffeine which can produce laxative effects, tannins which can cause stomach irritation & nausea on an empty stomach, and increased amounts of certain antioxidants that can hinder iron absorption. A 2017 review of studies notes that high levels of simple green tea extract have been associated with liver damage, jaundice, acute-hepatitis like injuries and even liver failure from catechins within green tea. [5]

How long does l theanine take to work ?

+ -

In human studies, increased alpha waves were generated 15 minutes after oral administration [6] and it has been shown to influence the secretion and function of neurotransmitters 30 minutes after ingestion [17]. Theertham et al suggest maximum uptake in the brain is usually within 30-40 minutes. [18]

Does theanine help sleep ?

+ -

No. It does not promote the onset of melatonin and it is not a sedative. Sleep inducers and sedatives normally induce drowsiness or sleep within an hour [17] whereas theanine, which achieves its maximum uptake in the brain within 30–40 minutes does not induce any sleep or drowsiness in the subjects [18].

what does theanine do how does l theanine work can l theanine help with anxiety l theanine for stress and anxiety l theanine dose for anxiety when to take l theanine l theanine cortisol

Apr 10, 2025

.home-carousel--image--loading::before { display: none; } .home-carousel--image--loading div { position: relative; } .home-carousel--image--loading div:not(:first-of-type) { display: block; }