There is no single best L-theanine and caffeine ratio established by the studies discussed here. When comparing formulas, look at both the amount of each ingredient and the ratio between them.
Whether you are choosing fuel for a workday, study session, or training routine, understanding those numbers can help you compare products. Here is what the research measured and how to read the formula behind Charge Energy Gummies.
For a convenient gummy option, GR Fuel Charge Energy Gummies pair 80 mg caffeine with 200 mg L-theanine in a two-gummy serving.
What Are Caffeine and L-Theanine?
Caffeine is a stimulant commonly found in coffee, tea, and energy products. L-theanine is an amino acid naturally found in tea. Researchers have studied the ingredients separately and together to explore their effects on attention, mood, and performance on mental tasks.
Two studies referenced throughout this article are Owen et al. (2008) and Haskell et al. (2008).
Is There a Best L-Theanine and Caffeine Ratio?
A 2:1 L-theanine-to-caffeine ratio means twice as much L-theanine as caffeine—for example, 100 mg alongside 50 mg.
Owen et al. (2008) used that pairing, while Haskell et al. (2008) used approximately 1.7:1. These were separate studies with different doses, rather than a direct test of which ratio works best.
Both absolute dose and ratio matter when comparing formulas. For example, 20 mg L-theanine with 10 mg caffeine and 200 mg L-theanine with 100 mg caffeine share a 2:1 ratio, but contain very different amounts.
A ratio alone cannot tell you how a product will affect you.
L-Theanine-to-Caffeine Ratios at a Glance
| Study or Formula | L-Theanine | Caffeine | L-Theanine : Caffeine |
|---|---|---|---|
| Owen et al. (2008) | 100 mg | 50 mg | 2:1 |
| Haskell et al. (2008) | 250 mg | 150 mg | About 1.7:1 |
| Charge (per two gummies) | 200 mg | 80 mg | 2.5:1 |
Ratios are shown as L-theanine : caffeine. Charge is included for formula comparison; it was not tested in either trial. GR Fuel Charge Blog_10.06.26
What Does the Research Show?
In Owen’s 2008 study of 27 healthy volunteers, the caffeine and L-theanine combination improved attention-switching speed and accuracy at 60 minutes compared with placebo. Participants were also less susceptible to distracting information during a memory task at 60 and 90 minutes.
Another 2008 trial, by Haskell and colleagues, tested 150 mg caffeine and 250 mg L-theanine separately and together. The combination improved several measures, including reaction time, accuracy on certain tasks, and mental-fatigue ratings. The researchers suggested that the combination may have a different effect profile from caffeine alone.
Together, these trials support the rationale for pairing caffeine with L-theanine for certain attention and cognitive tasks. Their findings apply to the ingredients and conditions tested; they do not establish equivalent results for Charge or everyday productivity.
What Is in Charge Energy Gummies?
Charge brings this ingredient pairing into a convenient, no-mixing format. Each serving is two Sour Berry Blast gummies. The jar contains 60 gummies, or 30 servings.
| Ingredient | Per Two-Gummy Serving |
|---|---|
| Caffeine | 80 mg |
| L-Theanine | 200 mg |
| PurpleForce® purple tea extract | 100 mg |
| VasoDrive-AP® | 128 mg |
| Vitamin B12 (MecobalActive®) | 2.4 mcg • 100% Daily Value |
With 200 mg L-theanine and 80 mg caffeine, Charge has a 2.5:1 L-theanine-to-caffeine ratio. Both amounts are disclosed, so you can see exactly what each serving provides.
See the Charge product page and Supplement Facts for the complete formula, ingredients, and directions.
Where Does PurpleForce® Fit?
Charge also contains PurpleForce® purple tea extract.
A 2020 study by Cesareo and colleagues examined 100 mg daily over eight days in 30 healthy men and reported differences in some exercise-performance and recovery-related measures.
This is preliminary ingredient research, separate from the caffeine and L-theanine studies. It does not establish immediate energy benefits or prove equivalent results for Charge.
Choosing Energy Gummies for Your Routine
Gummies offer a portable option for busy days, with no shaker or mixing required.
When comparing products, check the caffeine amount per serving, the serving size, and the disclosed amounts of other active ingredients.
Follow the product directions and account for caffeine from coffee, tea, and other sources. Consider your caffeine sensitivity and timing, especially if caffeine affects your sleep.
People who are pregnant or nursing, take medications, or have a medical condition should discuss caffeine-containing supplements with a qualified healthcare professional.
Frequently Asked Questions
What Does L-Theanine Do When Paired With Caffeine?
The trials discussed here found improvements in some attention and cognitive tasks. The specific findings varied with the dose, study, and measure assessed.
You can review the underlying research in Owen et al. (2008) and Haskell et al. (2008).
How Much Caffeine and L-Theanine Are in Charge?
Two Charge gummies provide 80 mg caffeine and 200 mg L-theanine.
That is a 2.5:1 L-theanine-to-caffeine ratio.
Do Caffeine and L-Theanine Guarantee No Jitters or Crash?
No. The cited trials do not establish that guarantee.
Your experience can vary with caffeine sensitivity, sleep, timing, and total intake. Monitor all your caffeine sources and follow the product directions.
Find Your Everyday Fuel
Charge puts disclosed ingredient amounts into a portable gummy format, with no mixing required. It is a convenient way to bring caffeine and L-theanine into your everyday routine.
Explore Charge Energy Gummies and review the full Supplement Facts to decide whether the formula fits your needs.
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.