Smarter L-Theanine on a black reflective table with L-Theanine supplements surrounding the bottle.
Smarter 250mg L-Theanine
Smarter 250mg L-Theanine
Smarter 250mg L-Theanine
Smarter 250mg L-Theanine
Smarter 250mg L-Theanine
Close up of Smarter L-Theanine supplements spilled on a table next to a bottle of Smarter L-Theanine.
Reviews 800,000+ orders
L-theanine + flaxseed oil liquid softgels

250 mg L-theanine. Zero caffeine. One softgel.

Smarter 250mg L-Theanine

A standalone 250 mg serving of L-theanine with 300 mg of flaxseed oil in one convenient liquid softgel. No caffeine, powder, scooping, or mixing - just a clearly labeled amount you can use on its own or as part of your existing routine.

250 mg L-Theanine per Softgel Zero Caffeine 300 mg Flaxseed Oil Third-Party Tested
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Third-Party Tested Independent quality testing
Benefits
  • L-theanine has been studied for its role in attention and cognitive performance.*
  • Supports a calm, relaxed state during everyday stress.*
  • Provides 250 mg of standalone L-theanine without caffeine.
Ingredients

Each liquid softgel provides:

L-Theanine - 250 mg
Flaxseed Oil - 300 mg

Other ingredients: softgel capsule (bovine gelatin, vegetable glycerin, annatto, purified water, berry flavor), beeswax, and sunflower lecithin.

50 softgels per bottle • 50 servings

Contains bovine gelatin. Not vegetarian or vegan.

Suggested Use

Take one softgel once or twice daily as needed, preferably on an empty stomach, or as directed by a healthcare professional.

Do not exceed the Suggested Use. Consult a healthcare professional before use if you are pregnant or nursing, take prescription medication, use medications that cause drowsiness, or have a medical condition.

Smarter Caffeine+™

Smarter Caffeine+™

Caffeine and L-theanine are commonly taken together. Added to the same order.

$35.00

One ingredient doing the talking.

250 mg L-Theanine

One clearly labeled serving in every softgel.

Zero Caffeine

Standalone L-theanine without adding another stimulant to your routine.

Liquid Softgel

Delivered with 300 mg of flaxseed oil in a convenient softgel format.

Flexible Use

One softgel once or twice daily as needed, according to the Suggested Use.

Smarter L-Theanine bottle

The amino acid found in tea - without the cup of tea.

L-theanine is a naturally occurring amino acid associated with Camellia sinensis, the tea plant. Unlike caffeine, L-theanine is not a stimulant. Smarter L-Theanine provides 250 mg in one clearly labeled softgel.

See Supplement Facts

250 mg L-Theanine

One standalone serving

0 mg Caffeine

No stimulant added

L-Theanine liquid softgel

300 mg Flaxseed Oil

Oil carrier inside the liquid softgel

What to look for in an L-theanine supplement.

The amount, added stimulants, delivery format, supporting ingredients, and testing are all worth checking.

Smarter L-Theanine What to Look For

L-theanine

250 mg

Amount clearly disclosed

Caffeine

None

Whether stimulants are included

Format

Liquid softgel

A format that fits your routine

Oil carrier

Flaxseed oil

Supporting ingredients disclosed

Testing

Third-party tested

Independent quality testing

800,000+ Orders since 2016
2016 Independently owned
USA Made and tested
100% Third-party tested
Why Smarter Exists

Built on formulas, not fame.

Smarter Vitamins wasn't built with celebrity endorsements, influencer hype, or trendy marketing. We built it the harder way: make thoughtful formulas, show you what's inside, and let the product earn the repeat order.

Clear labels. No proprietary blends. Ingredients chosen for a reason - not because they look good in an ad. 800,000+ orders later, we're still doing it the same way.

- The Smarter Vitamins Team

The standards behind every bottle.

U.S. Manufacturing

Produced in established U.S. facilities

Established 2016

800,000+ orders and counting

Straightforward Formulas

Non-GMO ingredients. No proprietary blends.

cGMP Manufacturing

Produced under current Good Manufacturing Practices

Third-Party Tested

Independent laboratory testing for quality

FDA-Registered Facilities

Manufactured in FDA-registered facilities

Why Smarter L-Theanine

Calm doesn't have to come with caffeine.

250 mg of standalone L-theanine in one liquid softgel - use it without adding another stimulant to your day.

A Clearly Labeled Serving

Every softgel provides 250 mg of L-theanine. No proprietary blend and no guessing at the amount.

Standalone L-Theanine

This formula contains no added caffeine, so you can use L-theanine without automatically adding another stimulant.

Different From Caffeine

L-theanine is an amino acid, not a central nervous system stimulant like caffeine.

Studied in Human Trials

Human research has examined L-theanine for attention and cognitive performance, although results vary by dose, task, and study design.

Research on Stress Response

L-theanine has also been studied during acute and everyday stress. Results are promising in some studies but not uniformly conclusive.

Liquid Softgel Format

300 mg of flaxseed oil serves as the oil carrier inside each softgel.

Use It When It Fits

The label allows one softgel once or twice daily as needed, preferably on an empty stomach.

Independent Quality Testing

Third-party testing adds another layer of verification beyond what's printed on the label.

250 mg L-theanine · 300 mg flaxseed oil · one softgel once or twice daily as needed

Smarter 250mg L-Theanine $20.00
The research

Research & References

Selected human research on L-theanine. These references examine L-theanine as an ingredient - not Smarter L-Theanine or this specific 250 mg softgel formulation.

01 Gerolymos C, Saddier E, Boyer L, Fond G. Cognitive and affective effects of L-Theanine: a systematic review and meta-analysis of 31 randomized trials. A systematic review and meta-analysis of 31 randomized controlled trials involving 1,168 participants. The analysis found a significant short-term effect on choice reaction time in healthy adults, while findings for stress, anxiety and other outcomes were less consistent. No serious adverse events were reported in the included studies. Molecular Psychiatry. 2026. 02 Hidese S, Ogawa S, Ota M, et al. Effects of L-Theanine Administration on Stress-Related Symptoms and Cognitive Functions in Healthy Adults: A Randomized Controlled Trial. A randomized, double-blind, placebo-controlled crossover study in 30 healthy adults using 200 mg of L-theanine daily for four weeks. Researchers evaluated stress-related measures, sleep-quality measures and cognitive performance. The dose and product tested differ from Smarter L-Theanine. Nutrients. 2019;11(10):2362.

These references are provided for educational purposes. Study doses, populations, formulations, and conditions may differ from this product. They are not clinical studies of Smarter L-Theanine or this specific formulation and should not be interpreted as evidence that this product diagnoses, treats, cures, or prevents disease.

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Good to know

FAQs

L-theanine is an amino acid found naturally in tea leaves, particularly Camellia sinensis.

Unlike caffeine, L-theanine is not a stimulant.

Smarter L-Theanine provides 250 mg per softgel.

250 mg is within the range commonly examined in human L-theanine research.

Published trials and systematic reviews have evaluated single and repeated amounts around 200 to 400 mg, although study designs and outcomes vary.

There is no FDA Daily Value or established recommended daily intake for L-theanine.

No caffeine is listed in the formula.

Each softgel contains 250 mg L-theanine and 300 mg flaxseed oil.

This makes it different from combination products that automatically pair L-theanine with caffeine.

Not necessarily.

L-theanine is often studied for relaxation and stress-response measures, but it is not a conventional sedative or sleep medication. Individual responses can vary.

If you feel drowsy after taking it, avoid driving or operating machinery until you know how it affects you.

L-theanine and caffeine have been studied together in human trials, but adding L-theanine does not guarantee that caffeine won't cause jitters, anxiety, increased heart rate, or sleep disruption.

If you combine it with coffee or another caffeine product, pay attention to your total caffeine intake and your individual response.

No guarantee.

Some studies have examined L-theanine and caffeine together, but effects depend on the dose and outcome being measured. For example, one controlled study found that L-theanine did not significantly reduce caffeine-related jitteriness, even though other cognitive effects of the combination were observed.

We would not market standalone L-theanine as a guaranteed caffeine-jitter antidote.

Follow the label: one softgel once or twice daily as needed, preferably on an empty stomach.

Some people use L-theanine earlier in the day, while others use it later. There is no single universally correct time because individual goals and responses differ.

There is no guaranteed onset time.

Some acute human studies measure outcomes within roughly 30 minutes to several hours after a single dose, while other research examines daily supplementation over several weeks.

How noticeable the experience is - and when - varies by person.

The 300 mg of flaxseed oil serves as the oil carrier inside the liquid softgel.

We do not claim that this amount provides a clinically meaningful omega-3, brain-health, or cardiovascular benefit.

Talk with a healthcare professional if you take prescription medication.

Caution is advised with medications that cause sleepiness, including certain sedatives, because combined use may increase drowsiness.

Consult a healthcare professional before use if you are pregnant or breastfeeding, take prescription medication, use sedative medications, have a medical condition, or are considering giving L-theanine to a child.

Safety during pregnancy and breastfeeding has not been adequately established.

The softgel contains bovine gelatin, so the product is not vegetarian or vegan.

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