Source Naturals Serene Science L-Theanine, with Suntheanine, 200 mg, 120 Capsules

The Source Naturals Difference: Suntheanine®

Source Naturals selects Suntheanine®, the purest and most extensively researched form of L-Theanine available. This patented amino acid is produced through a fermentation process identical to the compound found naturally in green tea, ensuring consistency and potency. Manufactured in the USA under strict Good Manufacturing Practices, each batch is tested for quality. With over 20 years of clinical research backing Suntheanine®, you can trust that you're getting the best.

What Is L-Theanine?

L-Theanine is an amino acid predominantly found in green tea leaves. Unlike many other relaxation supplements, it does not cause drowsiness. Instead, it supports a state of calm alertness by influencing brain chemistry, including levels of GABA, serotonin, and dopamine—key neurotransmitters involved in mood regulation, focus, and relaxation.

Each capsule of Source Naturals Serene Science L-Theanine delivers 200 mg of this unique amino acid, using Suntheanine®. With 120 capsules per bottle, it provides a two-month supply at a standard serving size.

How Does It Promote Calm Alertness?

The hallmark benefit of L-Theanine is its ability to promote a relaxed yet focused mental state. It achieves this without sedation, by encouraging alpha brain wave activity—the same pattern seen during meditation or light daydreaming. This state of "awake relaxation" helps quiet mental chatter while keeping you attentive and productive.

• Calm focus: Helps reduce mental noise while maintaining concentration.
• Stress response: May help ease occasional nervous tension without impairing cognitive function.
• Sleep quality: Whilst not a sedative, it can aid sleep by promoting relaxation before bed.

Interestingly, L-Theanine can also offset the jittery effects of caffeine, making it a popular addition to coffee or tea for smoother energy.

Who Might Find L-Theanine Useful?

• Students and professionals: Those needing to stay focused during demanding tasks or exams.
• Individuals with situational anxiety: People who feel nervous before presentations, meetings, or social events.
• Those seeking better sleep: Anyone wanting to unwind naturally without relying on harsh sleep aids.
• Creatives and meditators: Those aiming to achieve a flow state or deepen mindfulness practice.

L-Theanine is generally well tolerated, but it is wise to consult a health care professional before starting any new supplement, especially if you are pregnant, nursing, or taking medications.

Using L-Theanine Effectively

The typical serving for adults is one 200 mg capsule one to two times daily as needed. For daytime relaxation and focus, take one in the morning or early afternoon. For sleep support, take one about 30–60 minutes before bedtime. It can be taken with or without food. Some users find that combining L-Theanine with a small amount of caffeine enhances focus and creativity while reducing jitters.

Each bottle contains 120 capsules—up to 120 servings if taken once daily. Store in a cool, dry place away from direct sunlight.

Frequently Asked Questions

Can I take L-Theanine every day?

Yes, L-Theanine can be taken daily. It is not habit-forming and remains effective over time. Many people incorporate it into their daily routine for sustained calm focus.

Is L-Theanine safe for long-term uses?

L-Theanine has an excellent safety profile and is well tolerated. Studies indicate no significant adverse effects at recommended doses.

Will L-Theanine make me drowsy during the day?

No, L-Theanine promotes relaxation without sedation. Most users feel calm and alert, not sleepy, unless taken at very high doses or combined with other sleep aids.

Does L-Theanine interact with medications?

L-Theanine may interact with certain medications, especially those affecting blood pressure or the centre nervous system. Always consult your health care provider before combining supplements with prescription drugs.

*This product is not intended to diagnose, treat, or prevent any disease. Always consult a health care professional before starting any new supplement.