Richard J Bloomer¹ and Judi Quilici Timmcke²

¹Center for Nutraceutical and Dietary Supplement Research, College of Health Sciences, University of Memphis, Memphis, TN, USA
²Calerie Health, 200 Spectrum Center Dr Suite, Irvine, CA, USA

*Corresponding Author:Richard J Bloomer, Center for Nutraceutical and Dietary Supplement Research, College of Health Sciences, University of Memphis, Memphis, TN, USA.

Received: May 09, 2024; Published: June 14, 2024

Abstract

Dietary supplements have increased in popularity over the past two decades, with nearly 80% of American adults claiming to use at least one dietary supplement. One of the most commonly utilized supplement classes is that related to perceived energy and focus-with an estimated projected revenue exceeding $150 billion by 2031. While not all “energy” supplements contain caffeine or a derivative of this stimulant, most do-and for good reason: caffeine has been extremely well-studied, and it provides a favorable effect for the majority of users. That said, it is not without its concerns, namely the often-noted “crash” in the aftermath of the caffeine high. To offset this, two approaches are common: 1) reduce the dosage of caffeine delivered and 2) pair caffeine with an agent that may complement its effect while not requiring the same dosage of caffeine. One such ingredient is L-theanine. This amino acid has been reported to aid focus and mental clarity. The combination of caffeine and L-theanine has been investigated in controlled trials with success and is a widely used combination within the dietary supplement industry. In this brief review we discuss the noted mechanisms of action of both agents, the peer-reviewed literature supporting their independent and combined use, and the practical applications for individuals considering this dietary supplement duo.

Keywords: Focus; Energy; Performance; Dietary Supplement

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Citation

Citation: Richard J Bloomer and Judi Quilici Timmcke. “The Physiologic Benefits of Caffeine and L-Theanine". Acta Scientific Nutritional Health 8.7 (2024): 27-32.

Copyright

Copyright: © 2024 Richard J Bloomer and Judi Quilici Timmcke. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.