L-Theanine Supplements Compared
We currently recommend 4 L-Theanine supplements. The table below lines them up on what each label actually states: the form, how much is in a serving, how many capsules or servings are in the bottle, and how the extract is standardized. Under the table, each product has its own section on when and how to take it and what it pairs well with.
L-Theanine is an amino acid naturally found in green and black tea leaves, known for promoting calm, focused alertness without sedation. It's commonly paired with caffeine to take the edge off jitters while keeping the alertness.
| Product | Form | Serving | Count | Standardization | Also notable | Buy |
|---|---|---|---|---|---|---|
| GABA L-Theanine | Capsule | 150mg L-theanine + 750mg GABA | 120 | Combination formula | Magnesium, B6, B12 | Amazon |
| Nature's Trove L-Theanine | Capsule | 200mg | 365 | — | Non-GMO, Kosher | Amazon |
| NOW Foods L-Theanine | Capsule | 200mg | 120 | — | With inositol | Amazon |
| Sports Research L-Theanine | Softgel | 200mg | 120 | Suntheanine | — | Amazon |
How to choose a L-Theanine supplement
Typical dosage: Typical doses range from 100mg to 400mg, and it can be taken any time of day since it isn't sedating by itself.
Things to know: Generally very well tolerated with a strong safety record. Some people notice the calming effect more than others.
Serving sizes aren't always comparable between products. A concentrated extract and a whole-herb powder can list very different milligram amounts for a similar effect, so compare the standardization column, not just the serving.
L-Theanine
GABA L-Theanine
A combination formula — 750mg GABA plus 150mg L-Theanine per serving, with magnesium, B6 and B12. 120 capsules (2 per serving).
- Form
- Capsule
- Serving
- 150mg L-theanine + 750mg GABA
- Count
- 120
- Standardization
- Combination formula
- Also notable
- Magnesium, B6, B12
When to take it
This formula is best suited to the evening or to winding down after a stressful day. With 750mg of GABA per serving alongside L-Theanine, it is aimed at relaxation rather than daytime focus.
How to take it
One serving is two capsules, providing 750mg GABA and 150mg L-Theanine plus magnesium, vitamin B6 and B12. Take it with water, an hour or so before you want to relax or go to bed. If you already take a multivitamin or a magnesium supplement, check the totals so you don't double up.
What to combine it with
For daytime focus, a single-ingredient L-Theanine with coffee is a better fit than this formula. In the evening, it can sit alongside Bacopa Monnieri, which many people also take at night.
L-Theanine
Nature's Trove L-Theanine
200mg per capsule, 365 vegetarian capsules — over a year's supply at one a day. Non-GMO and Kosher.
- Form
- Capsule
- Serving
- 200mg
- Count
- 365
- Also notable
- Non-GMO, Kosher
When to take it
Take it any time of day. In the morning, take it with your coffee to smooth out caffeine jitters; in the evening, it can help you unwind, since L-Theanine is calming without being sedating. Many people feel the effect within 30 to 60 minutes.
How to take it
Each capsule is 200mg, a typical single dose. With coffee, the ratio most people use is about 2:1 L-Theanine to caffeine: one capsule with a cup of coffee (roughly 100mg of caffeine). With 365 capsules, the bottle lasts over a year at one a day.
What to combine it with
The classic pairing is caffeine: L-Theanine keeps the alertness and takes the edge off. It also combines well with Rhodiola Rosea for stressful days and Lion's Mane for a daily focus routine.
L-Theanine
NOW Foods L-Theanine
Double Strength 200mg, formulated with inositol. 120 vegetarian capsules.
- Form
- Capsule
- Serving
- 200mg
- Count
- 120
- Also notable
- With inositol
When to take it
Take it whenever you want calm focus: with your morning coffee, before a stressful meeting, or in the evening to relax. Effects are usually felt within an hour.
How to take it
Each capsule is 200mg of L-Theanine, formulated with inositol. One capsule is a typical dose. Take it with or without food. Pair one capsule with a cup of coffee for the popular 2:1 L-Theanine to caffeine ratio.
What to combine it with
Combine with caffeine for focused work sessions, or with Rhodiola Rosea on high-stress days. It also fits a daily stack with Lion's Mane and Bacopa.
L-Theanine
Sports Research L-Theanine
Double Strength 200mg using patented Suntheanine, in softgel form. 120 softgels.
- Form
- Softgel
- Serving
- 200mg
- Count
- 120
- Standardization
- Suntheanine
When to take it
Take it with your morning coffee for calm alertness, or in the evening to wind down. L-Theanine works within about 30 to 60 minutes and doesn't need to build up over weeks.
How to take it
Each softgel contains 200mg of Suntheanine, a patented, well-studied form of L-Theanine. Swallow one softgel with water, with or without food. Softgels are a good choice if you find capsules hard to swallow.
What to combine it with
Pairs naturally with caffeine at roughly 2:1 (one softgel with a 100mg cup of coffee). For stressful stretches, combine with Rhodiola Rosea in the morning. Avoid stacking it with a second L-Theanine product; one 200mg dose is plenty for most people.
Read more about L-Theanine
L-Theanine and Caffeine: Why This Combo Works (and How to Dose It) →
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