L-Theanine is a supplement that helps foster a calmer, more focused mind without making you drowsy, supporting stress relief and steady concentration for work, study, or busy days. The standout ingredient is l theanine supplement, a non-protein amino acid found in green tea. Source Naturals has built a decades-long reputation for pure, trusted supplements. Together, these elements help you feel calmer and more focused through daily routines.

Available Sizes & Variants:

60 capsules - handy daily dose for ongoing calm and focus

Benefits & Features:

• Promotes a calm, focused mind without sedating you.
• Supports stress relief for busier days with steadier mood.
• Aids attention and working memory in older adults during longer tasks.
• Pairs well with caffeine for enhanced focus without jitters.
• Calibrated formulation uses pure L-theanine with a small stabilising touch of calcium to help maintain the capsule's integrity, while Source Naturals' long standing heritage underpins trusted daily supplementation.

Source Naturals has built a decades long reputation for clean, reliable supplements. L-Theanine crosses the blood brain barrier and research suggests it can reduce stress and anxiety in stressful situations, helping you feel calm without sedation. Dr. Hidese of Osaka University led a meta-analysis supporting these calming benefits, making this a credible choice for everyday balance. Many customers pair it with magnesium glycinate or a vitamin d supplement as part of their daily wellbeing routine.

L-Theanine, Microcrystalline cellulose, gelatin (capsule), colloidal silicon dioxide and magnesium stearate.

• GTIN: 21078016465
• Manufacturer: Source Naturals
• Categories: Best SellersL-Theanine Supplements & TabletsNew ArrivalsNootropics SupplementsSleep & Relaxation SupplementsSource NaturalsStress Relief & Calming SupplementsSubscribe & Save ProductsSupplements for Anxiety
• Best buy: 6 - 24 months+

United Kingdom Shipping:

Orders placed by 2pm (Monday to Friday) are dispatched the same day. Orders placed after 2pm will be dispatched the next working day.

Free shipping on orders over £50 to the UK.

Returns: Our products are meant to make you feel healthy and at your best. If you need to return your item, you can do so free of charge within 30 days in the same original and unopened packaging. Subject to T&C's.

Consume one capsule once or twice a day with a glass of water. Standard dosage is: 3-6 capsules two times per day. They recommend to use between 1-2 capsules twice daily - up to 6 capsules with food twice daily

Please consult the product packaging for accurate instructions on how to use the product.

The Active Ingredient Is: L-Theanine

L-Theanine is basically a non-protein amino acid mostly found in green tea, recognised for helping create a calm, balanced mindset without making you sleepy.

This variant is usually sold as a pure amino acid, with source notes pointing to extraction from Camellia sinensis greens and its stability in vegan-friendly capsules.

What Does L-Theanine Do?

L-Theanine helps with normal cognitive and mood regulation by promoting a calm mind and aiding in stress response, which lines up with EFSA-backed ideas of relaxation and focus through natural amino acid activity.

Research from Dr. Hidese at Osaka University and colleagues found that L-Theanine links to reduced stress and anxiety in people under pressure, supporting its role in keeping a calm yet alert state.

This product is not intended to diagnose, treat, cure, or prevent any disease.

Why Source Naturals L-Theanine is Welzo Chosen

Source Naturals has built a solid reputation for quality and reliability in the supplement space, lining up with Welzo's criteria for trusted supplier partnerships. The brand is recognised for its specialised focus on amino acid–based calming ingredients, which complements our science-led approach to product curation. When weighing partners, our experienced team assesses manufacturer credentials, heritage, and ongoing commitment to quality; Source Naturals stood out thanks to its long-standing presence and clear alignment with our standards. You can get a sense of our approach from our expert team of doctors, nurses, and nutritionists and the criteria we apply to testing and certifications in the standards we enforce.

This brand’s quality mindset is shown in its product design and formulation, which uses L-theanine as the sole active ingredient in many versions, helping a calm mind without drowsiness. The evaluation process emphasised sourcing philosophy, manufacturing discipline, and clear quality practices, ensuring Source Naturals fits our product-fit for a calming, focus-supporting supplement. The collaboration rests on our thorough vetting by our expert team, confirming Source Naturals as a dependable partner for Welzo customers.