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.* 
Regular Price: $19.95 Sale Price: $14.96 ea - 25% Off
In stock
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$14.96
$19.95
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L-Theanine, Quantum

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.* 

L-Theanine, Quantum

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

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
DOES QUANTUM HAVE ANY MENOPAUSE-SUPPORT SUPPLEMENTS?
Quantum Women’s Power is formulated with powerful nutrients to support optimal functioning during menopause:

  • Libifem®. This fenugreek seed extract is clinically proven to support sexual health and promote menopausal comfort.*
  • LJ100®. Our Tongkat Ali ingredient is sourced from LJ100™, a standardized root extract of Eurycoma longifolia which consistently delivers evidence-based potency. Tongkat Ali root has a long history of safe use as a natural option for improving testosterone levels and supporting reproductive health.*
  • Women's Botanical Power Blend. This blend includes nutritive, zinc-rich pumpkin seed powder, hormone-balancing saw palmetto berry, and the energizing bioactive components from fermented cordyceps extract and American ginseng.*
WHAT ARE EXCIPIENTS?
Excipients are binders, fillers, and "glues" that are added to many supplements to prevent clumping of powdered ingredients and improve efficiency in manufacturing. Typically, excipients do not have nutritional value and their ingestion can cause adverse effects, toxicity, allergic responses, and drug interactions.

At Quantum Nutrition Labs, we do not use any non-nutritive excipients in the manufacturing of our products. Our products are designed to provide pure, clean nutritional supplementation without any toxic tagalongs that can harm the body.

Quantum Nutrition Labs offers capsules, powders, and liquid supplements, but not tablets. This is because tablets almost always require non-nutritive binding agents to manufacture. When you choose a Quantum Nutrition product, you can be assured that its contents are pure.

ARE QUANTUM NUTRITION SUPPLEMENTS GMO-FREE?
We use organic, non-GMO raw ingredients in our supplements whenever possible. The following formulations have been certified by a trusted non-profit organization called Non-GMO Project Verified:
WHAT IS THE HISTORY OF QUANTUM NUTRITION LABS (QNL)?
QNL was created by Dr. Robert Marshall, Ph.D., CCN, who practiced clinical nutrition for more than 30 years and hosted “HealthLine Now,” a radio show that helped listeners with their health and wellness goals. His whole foods approach to dietary supplementation, which included avoiding nonnutritive excipients and other common, commercially used additives, were, and still are, the foundation of our clean, high-quality, wellness products.

The philosophy behind our “quantum” approach to nutrition is that all living organisms possess a bioenergetic field that transcends physical matter. This biofield can be invigorated by whole food nutrients and phytochemicals that support the body's bioenergetic field, cellular health, and overall functioning. By exclusively utilizing the purest natural ingredients to create our products, Quantum Nutrition Labs aims to harmonize your body with the natural world and help you live your healthiest, most vibrant life.

ARE QUANTUM PRODUCTS CERTIFIED KOSHER?
We offer 52 products that are certified kosher by Orthodox Union Kosher, the world’s largest and most widely recognized international kosher certification agency.
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.
DOES QUANTUM TEST FOR STABILITY?
Yes, we test our products at a wide range of storage conditions, including stressed conditions to simulate advanced degradation scenarios that can include relative humidity up to 75% and temperatures as high as 104 degrees Fahrenheit to ensure the product remains stable when stored as directed on the label.

We also use nitrogen or argon flushes on many products to remove oxygen from their storage containers, extending the shelf-life. We also add moisture desiccants to keep the product dry.

Furthermore, we store our products in our exclusive VioliteTM containers. These dark violet-colored, polyethylene bottles are designed to prevent radiation damage to the ingredients by blocking light wave frequencies between 450 and 720 nanometers.

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