Skip to the beginning of the images gallery

L-Theanine, Quantum

Supplement

Find your Zen with L-theanine: Promotes calm, focus, and balanced energy naturally.

Stay Calm Under Pressure: Helps maintain a calm mindset during stressful moments.*

Boost Mental Clarity: Supports focus and concentration, even on the busiest days.*

Encourage Restful Sleep: Promotes relaxation and supports healthy sleep patterns without drowsiness.*

Clean and Effective: Free from unnecessary additives or fillers, this formula is designed for consistent safety, purity, and effectiveness.*

Item:

12851

Product Benefits

Calm, Focus, and Clarity for Active Lifestyles
Find your Zen with the clinically studied benefits of L-theanine—an amino acid from green tea leaves that promotes calm, focus, and mental clarity without the drowsy side effects Quantum L-Theanine delivers 200 mg dosage of L-theanine in every capsule, a clinically relevant dose used to support a balanced stress response, promote a positive mood and mindset, and boost cognitive performance.*

This clean-label L-theanine supplement is ideal for adolescents (12+) and adults seeking reliable support to maintain focus, composure, and balanced energy throughout busy days. With Quantum L-Theanine, you get trusted, targeted benefits for staying sharp and composed—whether managing stress, enhancing focus, or supporting relaxation.*

Why Choose Quantum L-Theanine?

Clean Label Commitment: Free from fillers, synthetic additives, and unnecessary ingredients—just pure, targeted support.
Third-Party Tested: Verified for purity, potency, and consistent efficacy.
Vegan-Friendly: Non-GMO, gluten-free, soy-free, and manufactured in a GMP-certified facility.
Caffeine Synergy: Smooths out caffeine’s energy peaks, delivering sustained focus while calming the jitters.*

What Makes Our L-Theanine Quantum?
Quantum L-Theanine is a clean-label supplement designed for purity and effectiveness. It is sourced from trusted suppliers and is 100% free from non-nutritive ingredients, binders, or excipients.

How Does It Work?

Quantum L-Theanine™ promotes calm and focus by:

Encouraging Alpha Brain Waves for a Zen State of Mind:
L-theanine promotes alpha brain wave activity, fostering a state of calm, focused alertness—like the mental clarity achieved during meditation. This helps you concentrate and stay composed, even in demanding situations.*
Influencing Neurotransmitters for a Balanced Stress Response:
L-theanine plays a key role in mood stability, focus, and cognitive performance by supporting neurotransmitters like GABA, dopamine, serotonin, and glutamate. This balance helps calm overstimulation while promoting emotional resilience and mental sharpness, even under pressure.*
Enhancing Caffeine Synergy for Sustained Focus:
L-theanine works compatibly with caffeine to smooth energy highs, reduce jitters, and maintain long-lasting focus. Together, they provide calm, steady energy, helping you stay productive without the crashes often linked to caffeine alone.*

FAQs

What are the benefits of Quantum L-Theanine?
Quantum L-Theanine™ promotes calm, focus, and mental clarity, helping to maintain a balanced stress response and healthy sleep patterns.*

Is it safe for adolescents and older adults?
Yes! Quantum L-Theanine™ is safe for adolescents (12+) and older adults, making it a versatile supplement for supporting calm and focus across all ages.*

How does it work with caffeine?
L-theanine complements caffeine by smoothing energy peaks and reducing jitters, creating sustained focus and calm energy without overstimulation.*

What is the recommended dose for L-theanine?
The clinically studied dose for adults and adolescents is 200 mg daily, typically in one or two divided doses.*

Can Quantum L-Theanine™ be taken daily?
Yes, Quantum L-Theanine™ is formulated for safe, daily use to support relaxation, focus, and a balanced stress response.*

Ingredients

Serving Size 1 Capsule
Servings Per Container 60

L-Theanine 200 mg

Other Ingredients: Organic Rice Concentrate, Plant-Source Capsules (cellulose, water), Organic Rice Bran

Recommended Usage

Quantum L-Theanine Recommended Use

Adults: Take 1 capsule, 1-2 times daily with meals or as directed by your healthcare professional.

Adolescents (12-18): Take 1 capsule daily with meals or as directed by a healthcare professional.

Product FAQ

ARE THERE SUPPLEMENTS THAT CAN HELP ME SLEEP?

Clinical evidence supports the use of several different supplements for promoting restful sleep. These include:

Melatonin. This sleep-promoting hormone is naturally released by the body in the hours leading up to bedtime. Melatonin supplementation may help support a healthy sleep-wake cycle especially when you’re trying to realign your natural sleep rhythm due to shift work or jet lag. However, it’s important to use melatonin cautiously as scientists lack information on its long-term effects.
Magnesium. Magnesium deficiency is increasingly common and may cause nighttime symptoms like leg cramps. Easy for the body to absorb, magnesium glycinate is known for its calming properties and may promote relaxation and sleep. Research indicates that supplementing with magnesium may help some individuals fall asleep faster and stay asleep longer.
Lavender (Lavandula angustifolia). Essential oil components of English lavender, like linalool and terpineol, support sleep by reducing stress and activity in the central nervous system, lowering blood pressure, and potentially improving mood. Lavender has a long history of use in natural medicine for its calming properties and possesses limited risk for side effects. Lavender oil can be taken by mouth or administered through aromatherapy.
Valerian (Valeriana officinalis). This root extract contains many bioactive chemicals that can have moderate sedative and relaxing effects on the body. A possible mechanism by which valerian may improve sleep is by increasing the amount of gamma-aminobutyric acid (GABA), a calming neurochemical in the brain.11 Some studies have shown valerian to help people fall asleep faster and sleep more throughout the night.
L-theanine. An amino acid found in tea leaves, L-theanine is another substance that triggers the release of GABA.12 L-theanine naturally calms anxiety, enhances relaxation, and provides a safe natural sleep aid without drowsiness.13 L-theanine should be used carefully as it can interact with other medications.

Explore Quantum Nutrition Labs’ specially formulated sleep-promoting supplements at Supplements for Sleep.

HOW ARE YOUR SUPPLEMENTS TESTED?

We guarantee the quality and consistency of every supplement we offer by using cutting-edge testing equipment and practices and running multiple tests on each ingredient, including:

Heavy metal testing
Microbial testing for contaminants
Microscopy to evaluate botanical identity
High-performance thin layer chromatography, which looks at levels of active phytochemicals within a plant

At QNL, our rigorous testing protocols guarantee that our products are free from toxins, pesticides and herbicides, and steroid and antibiotic residues.

In addition to performing in-house testing, we engage numerous third parties to validate the quality of our products. Our manufacturing facility is certified by independent testing agencies like USP and NSF. Many of our products are further certified by the Non-GMO Project, OU Kosher, and USDA Organic.

Lastly, the vitality of the ingredients tested is screened using energetic assessment methods based on an applied kinesiology method known as the Bi-Digital O-Ring Test, developed by Dr. Yoshiaki Omura.1 This method has been an integral part of QNL’s ingredient sourcing and formulation development.

MY ORDER ARRIVED AND THE CAPSULES LOOK DIFFERENT THAN LAST TIME.

We source ingredients only in their unrefined state, so you may notice that the color, texture, and even odor of a product may vary somewhat between batches and across seasons. Despite these natural variations, each product contains its exact formula and is rigorously tested for purity.

HOW CAN I MAKE CHANGES TO MY ORDER?

Once your order is placed and you have received an order confirmation, we are unable to change your order to add or remove items. To purchase additional products, you will need to place a new order. You may cancel your order before shipment by calling 1-800-370-3447.

WHAT IS THE QUANTUM PLANT MULTI-VITAMIN?

Quantum Plant Multi-Vitamin is a pure, plant-based, all-in-one daily supplement that offers a complete array of essential vitamins and minerals to support brain, bone, immune, and cardiovascular health while supporting pH balance with its plant-based, alkalinizing ingredients.* This multi-vitamin is made up of organic, non-GMO fermented greens and whole-food ingredients for maximum bioavailability and absorption with no added synthetics. For additional information, check out our Quantum Plant Multi-Vitamin blog post.

DO QUANTUM PRODUCTS CONTAIN HYDROGENATED OIL, FLAVORING ADDITIVES, ARTIFICIAL COLORS, OR FRAGRANCE?

No, we do not use hydrogenated oils, nor do we use any additives that alter the flavor, color, or fragrance of the product. Our products are also made without:

Added preservatives like potassium sorbate
Non-nutritive excipients like magnesium stearate
Talcum powder, an anti-clumping powder and suspected carcinogen

WHY IS IMMUNE SUPPORT IMPORTANT?

The immune system is an incredibly complex network of organs, tissues, glands, and cells that find and respond to harmful foreign invaders like viruses and bacteria, which can cause disease. The immune system relies on various micronutrients, such vitamin A, vitamin C, vitamin D, vitamin E, selenium, beta-carotene, iron, and zinc, for optimal functioning. Deficiencies in these and other phytonutrients can lead to increased risk for infection and longer recovery periods.

Ideally, we would get all the essential immune-boosting vitamins and minerals we need by eating nutritious foods. However, it can be difficult to maintain a balanced diet for many reasons. Even if you consume a nutrient-rich diet, industrial farming practices have eroded the microbiome of the soil our food is grown in and with it the nutritional value of most food products. As a result, it's critical to take targeted supplements that support your immune system.

Shop all

L-Theanine, Quantum

Product Benefits

Have more questions?

Reviews