While I’ve tried sleep supplements containing both theanine and Kava, there are a lot of differences between the two substances. Both can have a positive impact on sleep, but it’s important to keep a few things in mind before trying, especially since Kava has been linked to potentially harmful side effects.
First, theanine is an amino acid that’s been linked to feelings of calm without sedation. This makes it a pretty solid compliment to existing sleep stacks. For example, True Athlete added l-theanine to their standard ZMA stack to improve upon an already excellent and straightforward sleep supplement. (Learn the difference between theanine and l-theanine here.) Theanine is actually seen more often in concentration/brain supplements (generally referred to as “nootropics”) like Alpha BRAIN; some research suggest that when paired to caffeine or other nootropic compounds, theanine increases the perceived benefits to cognition and focus.
Kava, on the other hand, is not an amino acid, but actually a plant extract. Also known as Kava Pepper, Ava Pepper, or Kava Kava, it’s an herb that some cultures in the South Pacific traditionally drink to reduce anxiety and aid with sleep.
It’s now often sold as an extract in supplement form, and I’ve found it beneficial to my sleep, but there are a few potential drawbacks. (Read my full review of Kava Kava by Natrol.) First an foremost is a potential link between Kava and liver toxicity. In some clinical and research observations, human subjects have in rare cases experienced liver toxicity and damage from kava extracts and supplements. Some of this toxicity, research suggests, may be due at least in part to poor sourcing practices.
Kava may also interact with other drugs, pharmaceuticals, and medicines. While I’m not a doctor, it’s probably a good idea to speak to your physician or a medical professional before using Kava with prescription medications. This is especially important to note since the exact mechanisms by which Kava could be toxic to humans remain unclear.
Overall, theanine is a more widely-used compound that is a part of several of my favorite supplements for relaxation and sleep (see ZMA and Alpha BRAIN above). Like I said, I’ve had success with Kava for improving my sleep, but there are enough good supplements that don’t contain it to where I don’t think it’s a necessary part of my routine.