Suntheanine vs. L-Theanine: Differences and What’s Better

We want to eliminate your confusion about the properties of L-theanine and Suntheanine so that you can make an educated decision.

Suntheanine vs. L-Theanine: Differences and What’s Better

L-theanine is a popular nootropic choice that offers significant results and stacks well with other natural ingredients.

If you have been shopping around for the best l-theanine supplements, you probably came across Suntheanine and wondered what the difference was.

The differences between Suntheanine and L-theanine are subtle but can impact the cognitive benefits and effectiveness.

Because of this, it is good to compare and contrast the two with their advantages and disadvantages.

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What’s The Difference Between Suntheanine and L-Theanine?

Both l-theanine and Suntheanine are amino acids that offer benefits to cognition and mood. However, both are unique because they are derived using different processes.

The differences of pros and cons of each can provide determining factors to help you decide which one is best for you.


Suntheanine brand is a form of l-theanine produced by Taiyo International Inc., a Japanese green tea manufacturer.

Suntheanine l-theanine is produced via a patented process that mimics the natural process in green tea leaves resulting in a pure form (1).

Taiyo’s patented pure form of l-theanine is produced using this process is isolated from another component of green tea, d-theanine, to provide a cleaner effect.

Suntheanine Benefits

Suntheanine is a popular form of l-theanine for anxiety, stress relief, and many people prefer it for relaxing.

However, it is also a component in many nootropics because it also influences cognitive abilities. Suntheanine is potent and effective for many people, and it has certain benefits compared to regular l-theanine.

Some people believe Suntheanine crosses the blood-brain barrier more readily. Not only that, but it is more potent and concentrated because Suntheanine is the pure form of l-theanine.

These benefits mean that less of the compound has to be taken to obtain the same result.

Also, some experts claim that d-theanine may inhibit the absorption of l-theanine in the body, reducing the effects. However, there is limited clinical research that proves, or disproves, this idea.

Finally, since Suntheanine isolates l-theanine without d-theanine, then it provides only the benefits of l-theanine.

This means it may be better to offer a clean, smooth sense for promoting concentration and focus without notable side effects like drowsiness or nervousness.

Disadvantages of Suntheanine

Suntheanine also has a couple of disadvantages. First, since it is produced via a patented process, manufacturers are more expensive, which increases the price.

Also, since it is less common than regular l-theanine, it may be harder to find a blend or stack that has all the dietary supplements you want together.


L-theanine is derived as an extract of green tea leaves, resulting in a naturally occurring amino acid. It stimulates alpha brain waves and increases alpha brain wave activity (2).

This primary activity causes the beneficial quality. Therefore, the amino acid l-theanine is recognized as a nootropic that can provide a wide range of beneficial effects without significant adverse reactions.

L-Theanine Benefits

It is proven that l-theanine has many benefits, some of which are more powerful for some people than the effects of Suntheanine.

While the d-theanine found in regular l-theanine supplements can take up space without offering effects, we have found that the relaxation effect is more substantial with l-theanine than with Suntheanine.

Since it is more calming, it may have better anti-stress effects. It is also easier to stack with other stress-reducing supplements for a beneficial combination.

Not only that, but these beneficial effects make it a superb choice for people who have insomnia, and it can help with the quality of sleep.

It is more affordable than Suntheanine, making it an excellent choice for people with chronic anxieties, poor sleep quality, poor mood, or other daily problems.

L-theanine is also easier to stack with other nootropics because of its affordability and availability.

Many blends containing l-theanine also target specific effects like heightening mental acuity, promoting concentration, or relieving tension.

Disadvantages of L-Theanine

The biggest downside compared with Suntheanine is that you will have to take more than you would with the concentrated form.

Also, some people find it makes them more groggy or fatigued than they felt with the patented pure form.

Suntheanine or L-Theanine: The Comparison

Now that you know the primary differences, benefits, and downsides, you may find it helpful to see a complete comparison of the effects and performance of the two forms that we evaluated.


While clinical research suggests that both forms work in the same way by influencing neurotransmitters, some experienced users disagree.

Both provide a relaxation effect, an alert mental state, and overall brain health, but there may be some efficacy differences for different desired results.

While this could be a placebo effect, it could also be caused by different purity levels. Many users find that l-theanine has better efficacy for relaxation and sleep.

Clinical research suggests that the d-theanine competes with l-theanine, which may lessen the effects on some neurotransmitters, like dopamine (3).

This may lead to more tranquility and a relaxed feeling in much the same way you would get if you sipped on green tea.

Conversely, Suntheanine may have more cognitive benefits and cause feelings of focus, alertness, and mental acuity. Therefore, Suntheanine is preferred for its efficacy in reducing negative feelings and eliminating brain fog or mental fatigue.

It may also help improve learning performance, and Suntheanine is also the most potent form.


Suntheanine is the pure L isomer theanine, meaning that with identical doses, you would get more l-theanine with Suntheanine. However, the purity of l-theanine can be drastically different depending on the specific product.

Research estimates find that the best l-theanine supplement can be 50% or more pure, but the lower quality options can land at as little as 2% purity (4).

For Suntheanine, it will be around 98% pure. Therefore, a 100 mg dose of Suntheanine will provide about 98 mg of l-theanine (5).

To compare, 100 mg dosages of l-theanine can contain as little as 2 mg and as much as 50 mg or more, making it a similar potency to Suntheanine.

Because of this, you can know what exactly you are getting with Suntheanine. However, if you prefer l-theanine, you want to ensure that you get it from a reputable supplier that regularly tests their products.

It may take a few tries to get the proper dosage of either, but usually, a dose will be somewhere between 50 and 200 mg, and some people take that twice a day.

Side Effects

The negative side effects of both are usually very mild. Since Suntheanine is more potent, it is slightly more likely to cause adverse side effects with overdose. You should be careful taking either close to bedtime because it can disrupt sleep.

The most common side effects are headaches, nausea, and irritability. However, combining with other ingredients, like caffeine or a supporting supplement, can also increase the likelihood of side effects.

If you experience side effects, then reduce the amount you take. You should also be cautious mixing l-theanine with prescription drug administration.


Suntheanine has higher purity and is manufactured using a patented process that mimics the process in green tea. Unfortunately, it is more expensive.

Typically Suntheanine will be around 30 percent more costly than l-theanine. This can add up over time, especially if you plan on using the supplement every day.

L-theanine is very affordable, even with quality products from reputable brand name companies. If you are on a budget, it could be the best choice. However, you do get more bang for your buck with Suntheanine.

Which Nootropic Is Better To Choose?

Both l-theanine and Suntheanine can be beneficial for relaxation, attention span, alert mental state, improved learning performance, and promoting calm energy.

Some people prefer one, while others prefer the other because each has its unique properties and effects. L-theanine and Suntheanine are two of the most popular options to stack with other supporting supplements and nootropics.

The best l-theanine supplement stack on the market is Mind Lab Pro because it combines the perfect amounts of complementary ingredients and Suntheanine for well-rounded and robust effects.

In addition, it uses different mechanisms to support overall cognitive health and use for stress.

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Every ingredient found in Mind Lab Pro offers benefits that complement the effects of Suntheanine for full-spectrum cognitive performance and anxiety relief.

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