Does Green Tea Extract Keep You Awake?

Green tea extract has long been associated with antioxidant properties, fat metabolism support, and increased energy. However, alongside these benefits, many people express concerns that using green tea extract may lead to restless nights and difficulty falling asleep.

In this article, we will take a closer look at what’s actually inside green tea extract and compare it to other common stimulants. From there, we’ll try to answer the question: Does green tea extract keep you awake?

What’s in Green Tea Extract That Might Affect Sleep?

In terms of composition, green tea extract contains three primary groups of active compounds that can directly or indirectly affect the central nervous system: caffeine, L-theanine, and catechins, especially EGCG.

Starting with caffeine, this is a well-known central nervous system stimulant that works by blocking adenosine receptors in the brain, making you feel more alert and less sleepy. If you’re a regular consumer of coffee or green tea, this name is likely familiar.

For those who are sensitive to caffeine, even a small dose of around 30 to 50 mg may prolong the time it takes to fall asleep. In a 2023 study, participants who consumed caffeine showed a marked increase in WASO (wake after sleep onset) episodes compared to the non-caffeine group (Baba, et al. 2023).

However, what sets green tea apart from coffee is the presence of a compound called L-theanine. L-theanine is an amino acid found in tea leaves that is believed to help calm the nervous system without causing drowsiness.

Some studies suggest that L-theanine may promote alpha brain waves, which are associated with relaxation (Kobayashi, et al. 2023). In a separate 2019 study, L-theanine was also linked with improved sleep quality in individuals under prolonged stress (Shinsuke, et al. 2019).

Lastly, a defining component of green tea extract is the group of catechins, most notably epigallocatechin gallate (EGCG). EGCG does not appear to have a direct influence on sleep metrics such as latency or duration.

Some preliminary research suggests that EGCG might influence neurotransmitters like GABA and dopamine, potentially affecting mood and alertness cycles. However, these effects are not yet well-established and require further human studies to confirm.

How Much Caffeine Is in Green Tea Extract Compared to Coffee?

The caffeine content in green tea extract can vary significantly depending on the formulation type (capsule, powder, liquid), dosage, and extraction method. Below is a comparative table showing the average caffeine content in green tea extract and some common beverages:

As seen in the table, green tea extract provides significantly less caffeine per serving compared to coffee or energy drinks. However, when consumed in high doses or multiple times per day, especially in combination with other caffeine sources, it may still influence sleep patterns.

Can Green Tea Extract Really Keep You Awake?

Based on the scientific data discussed above, in some cases, the answer can definitely be yes! A meta-analysis published in Sleep Medicine Reviews in 2017 indicated that caffeine, even at moderate doses (~50 mg), may reduce deep sleep duration and increase nighttime awakenings (Clark, et al. 2016).

However, the same review noted that this effect does not apply evenly to everyone. Genetics, caffeine sensitivity, and liver metabolism speed (CYP1A2) can all cause the same caffeine dose to significantly affect one person, while barely impacting another.

In addition, timing plays a critical role. Drinking green tea in the morning allows the body to metabolize and eliminate most caffeine before bedtime—or simply by the time its effects wear off. In contrast, consuming green tea after around 3 PM can disrupt circadian rhythms and lower sleep quality.

On a Reddit thread discussing this topic, many users reported needing to consume green tea or its extract before 3–4 PM to avoid sleep disruption. Others said that even if it didn’t affect sleep onset, it still influenced the quality of their sleep.*

In one small-scale study with a 400 mg caffeine dose, participants who consumed caffeine within 12 hours of bedtime showed increased sleep latency, disrupted sleep, and noticeably reduced sleep quality. The study also advised limiting caffeine intake to at least 6 hours before sleep (Drake, et al. 2013).

As such, using caffeine in the late afternoon or evening can indeed lead to sleep difficulties, though the symptoms and severity vary based on individual factors such as dosage, timing, and personal sensitivity.

However, the combination of caffeine and L-theanine also plays a regulatory role. When used in the right ratio (L-theanine ≥ caffeine), the stimulating effects may be balanced out, resulting in gentle alertness without overstimulation.

When to Take Green Tea Extract to Avoid Sleep Disruption

To enjoy the benefits of green tea extract without compromising sleep, here are some practical recommendations you can start applying right away:

• Take it in the morning or before 2 PM: Caffeine has a half-life of about 5–6 hours. Using it after this window may leave your body still stimulated by bedtime, interfering with sleep quality.
• Consume it with a main meal: As with other substances, taking green tea extract with food slows caffeine absorption into the bloodstream, which can reduce the likelihood of sudden stimulation.
• Choose formulas with L-theanine: The ideal product should contain twice as much L-theanine as caffeine. For example, a formula with 30 mg of caffeine should also include at least 60 mg of L-theanine. This allows the calming effect of L-theanine to counteract the stimulant properties of caffeine.
• Avoid combining with other caffeine sources: Lastly, if you're sensitive to caffeine, you should closely monitor total daily intake, including caffeine from coffee, soft drinks, chocolate, and other supplements.

Conclusion

By now, you’ve likely found the answer to the question, "Does green tea extract keep you awake at night?" In summary, green tea extract can be a valuable companion during the day, helping to boost alertness, improve focus, and maintain energy for daily activities.

However, using it in the evening should be carefully considered, as the caffeine it contains may disrupt your sleep. The best approach is to avoid green tea extract later in the day. For those who are sensitive to caffeine or have trouble sleeping, the golden rule is to take your last dose before 2 PM.