L-Theanine Vs L-Threonate: Which Is Better? & How To Combine

In recent years, Dr. Andrew Huberman—a neuroscientist and professor at Stanford University—has popularized a nighttime supplement protocol often referred to as the “sleep cocktail”, includes the following ingredients and dosages (Huberman, 2025) [7]:

• 145 mg Magnesium Threonate or 200 mg Magnesium Bisglycinate
• 50 mg Apigenin
• 100–400 mg L-Theanine
• (Optional, taken 3–4 nights per week):
• 2 g Glycine
• 100 mg GABA

Two of the most discussed ingredients in this protocol—L-theanine and Magnesium L-threonate—have drawn particular attention for their potential roles in supporting a calm mental state and maintaining cognitive resilience under stress.

While both compounds are widely available as dietary supplements, many people wonder: Which one offers more noticeable cognitive benefits? And can they be effectively combined for enhanced results?

If you’ve ever felt like your brain is running like an old laptop—sluggish, overwhelmed, and unable to focus—you're not alone. Difficulty concentrating, frequent fatigue, and mental fog are common signs of cognitive overload.

In this article, we’ll explore the characteristics of L-theanine vs. Magnesium L-threonate, their potential cognitive applications as studied in clinical and preclinical settings, and how they may be strategically paired to support mental clarity and focus.

Comparison Table of L-Theanine and Magnesium L-Threonate

About L-Theanine

What is L-Theanine?

L-theanine is a special compound found in tea leaves, especially green tea and some mushrooms. L-theanine is also found in matcha. This compound is often used for its calming properties without the associated effects of drowsiness or lethargy.

In addition, L-theanine also has the ability to produce neurotransmitters that promote improved mental health such as reducing stress, increasing concentration, and regulating flow to the brain.

Typically, each cup of green tea contains 20-30mg of L-Theanine (Baba, et al. 2021) [1], depending on the quality of the tea you use. Therefore, compared to an L-theanine supplement, you need to drink 7-10 cups of tea to get the same amount of L-theanine.

L-Theanine Health Benefits

L-Theanine operates through a fascinating mechanism that few natural compounds can replicate. By interacting with alpha brain waves and key neurotransmitters, it significantly benefits mental well-being.

First, it helps combat stress. L-Theanine stimulates cortisol production to manage daily stressors such as work deadlines, household chores, or noisy children.

To clarify this effect, a study was conducted on over thirty adults. One hour after consuming L-Theanine, their salivary cortisol response to stress decreased within three hours, and resting-state alpha wave activity significantly increased. These effects were more pronounced in individuals with severe symptoms. (White, et al. 2016) [2].

The study also highlighted L-Theanine’s role in enhancing focus, may influence physiological responses related to stress, including blood pressure regulation, as seen in some studies.. However, further research is needed to confirm these findings.

Another study found that L-Theanine offers neuroprotective benefits for adolescents:

"L-Theanine modulates GABA, dopamine, and glutamate levels in various brain regions and exhibits neuroprotective properties." (Felice, et al. 2020) [3].

Beyond scientific studies, a small Reddit survey on L-Theanine’s mental health effects revealed insightful statistics:

• “About 25-38% of users said they noticed benefits from l-theanine in reducing stress.
• 13-18% of users mentioned the effect of increased focus thanks to L-theanine.
• 12-15% of users mentioned improved sleep.”

L-Theanine Side Effects

Since L-Theanine is derived from green tea, it is generally considered safe. However, it can still cause side effects, including:

• Digestive issues like nausea, bloating, and indigestion (often with excessive intake).
• Lowered blood pressure.
• Headaches.

Side effects may vary based on individual health conditions and sensitivity. The most common complaints include mild headaches and digestive discomfort.

Some anecdotal reports highlight these potential reactions. For instance, one Reddit user, RouquineCT, noted: "I wish it worked for me! It makes me feel very calm and sleepy, but I also get headaches. Has anyone else experienced this?"

While these side effects appear to be relatively uncommon, individuals considering L-Theanine supplementation should start with a lower dose to assess their tolerance before.

About Magnesium L-Threonate

What is Magnesium L-Threonate?

For those who frequently experience Magnesium deficiency, this compound may not be unfamiliar. Similar to L-theanine, Magnesium L-threonate is an amino acid used to supplement Magnesium with higher bioavailability and easier absorption.

Magnesium L-threonate has been studied for its potential role in supporting neurological processes and mental clarity in individuals with magnesium deficiency. Many sources suggest that it also pairs perfectly with L-theanine to create an effective formula for improving mood and alleviate stress.

Notably, Magnesium L-threonate is a combination of Magnesium and L-threonate, formed during the metabolism of vitamin C in the body. As a result, this compound is nearly impossible to obtain through food sources and is typically synthesized in laboratories or naturally occurring within the human body.

Reaching an equivalent dose of 200mg of Magnesium L-threonate through food is virtually impossible since it is not naturally present in significant amounts. Therefore, supplementation through dietary supplements is the most effective method of achieving adequate intake.

Magnesium L-Threonate Health Benefits

To clarify the health effects of L-threonate, scientists have conducted various studies. In addition to addressing Magnesium deficiency, numerous research participants have reported unexpected benefits from this compound, including:

• Improved sleep quality: A large-scale review of existing studies on Magnesium revealed that it significantly enhances sleep quality. This includes factors such as time to fall asleep, sleepiness levels, snoring, and overall restful sleep duration. The effects were particularly noticeable in individuals who did not consume enough Magnesium in their daily diet (Arman, et al. 2022) [4].
• Alleviation of stress: Through observations and statistical analysis, scientists concluded that individuals with stress are more likely to suffer from severe Magnesium deficiency. Conversely, lower Magnesium levels are also linked to worsening depression symptoms. This partially explains postpartum depression in women, as Magnesium is transferred from the mother to the baby through the bloodstream (Serefko, et al. 2013) [5].
• Additionally, some preliminary evidence suggests that Magnesium has a certain level of effectiveness in reducing anxiety and cognitive stress, alleviating symptoms of anxiety and mental fatigue caused by neural overstimulation (Boyle, et al. 2017) [6].

In an article on Wellness Hub,  Dr. Katie Brown emphasizes that Magnesium L-threonate has the ability to cross the blood-brain barrier, support cognitive function, and may reduce stress,...

Magnesium L-Threonate Side Effects

In general, supplementing with Magnesium L-threonate does not pose significant health risks when used correctly. Symptoms such as headaches, nausea, indigestion, and fatigue often occur when the recommended dosage is exceeded. Occasionally, individuals may also experience drowsiness or a lack of alertness.

For this reason, it’s essential to carefully select the right Magnesium supplement for your specific needs. If you experience any concerning symptoms, discontinue use and consult a healthcare professional promptly.

Magnesium L-Threonate vs L-Theanine: Which is Better?

Both of these compounds have impressive benefits for mental health.

On one hand, Magnesium L-threonate enhances cognitive function, crosses the blood-brain barrier, and increases Magnesium levels in the brain, which helps improve memory and learning abilities. Magnesium is involved in over 300 biochemical reactions, playing a crucial role in maintaining nervous system function, improving memory, and enhancing information processing.

On the other hand, L-theanine influences alpha brain waves, promoting relaxation and mental stability without causing drowsiness like sedatives. L-theanine also helps reduce nighttime awakenings and improves overall sleep quality.

That being said, both can become "unpleasant foes" if taken in excessive amounts. To put it humorously, overdosing on Magnesium L-threonate could make your stomach feel like a rock concert, while too much L-theanine might make your mind as noisy as living next to an opera house. So, be mindful of your intake!

Overall, both compounds serve as powerful allies for mental well-being—when used in moderation. But have you ever wondered if they could be even better when combined?

In addition to comparing L-Theanine and L-Threonate, people also draw comparisons between L-Tryptophan and L-Theanine to determine which one is more effective for sleep.

Can You Take L-Theanine and Magnesium L-Threonate Together?

Absolutely! Combining L-theanine and Magnesium L-threonate creates a synergistic effect that supports neurological health. By taking these two together, you may experience cognitive improvements, stress and fatigue reduction, mood enhancement, and better sleep quality.

Additionally, this combination may support memory formation and recall, enhance mental clarity, and boost alertness.

A verified Amazon customer, CElizab, gave a 5-star review for a supplement containing both compounds, stating:

“This supplement is INCREDIBLE! I actually only need to take one capsule & it's lights out for me for 8 hours! I wake up refreshed & renewed, ready to take on my day! No grogginess as it's an all-natural supplement! Thank you for this product!”*

The final verdict? Sleeping like a baby!

Potential Side Effects of Taking L-Theanine and L-Threonate Together

When using this combination formula, you may experience any side effects that l-theanine and Magnesium l-threonate can bring. In particular, a few common symptoms can be summarized as follows:

• Drowsiness, lack of alertness.
• Headaches with varying degrees of severity.
• Digestive discomfort.
• Low blood pressure.

In general, these are not all the side effects that you may experience. Sometimes, you may not experience any of the above symptoms. Therefore, before using any substance, consult your doctor and start with a small dose to monitor your body's manifestations for appropriate adjustments!

How to Take L-Theanine and L-Threonate Together

There aren’t many detailed guides on how to combine these two, but according to Dr. Andrew Huberman from Stanford University, you can take them as follows:

• Magnesium L-threonate: The recommended dose is 1,000 - 2,000 mg per day, preferably taken with meals. It’s best to split the dosage throughout the day for better absorption.
• L-theanine: Adults should take 250 mg once or twice daily. You can even combine them into a single capsule for convenience.

Alternatively, you can look for pre-formulated supplements that already contain both compounds for easier intake.

Conclusion

The noise of honking cars, distracting sounds, and the pressures of exams and work may finally have a solution. L-theanine and L-threonate make a perfect duo for improving mental health and relaxation. However, always choose a safe supplement source, listen to your body's reactions, and seek medical help if any unusual symptoms arise.