Wait 90 to 120 minutes after waking before consuming your first dose of caffeine (1 to 3 mg per kg of body weight) to allow the body's natural waking mechanisms to activate and to avoid the afternoon crash.

noli's read

This hypothesis relies on real biological concepts, such as the natural release of cortisol upon waking and the role of adenosine in the sensation of fatigue. However, a systematic review of the literature published in 2024 by the Journal of the International Society of Sports Nutrition (JISSN) concludes that there is no clinical evidence showing that this delay prevents the afternoon crash. In reality, for habitual consumers, caffeine tolerance strongly mitigates its impact on morning cortisol. Furthermore, as adenosine is already at its lowest upon rising, delaying coffee does not promote additional 'clearance' of this molecule. This mid-day crash stems more from a natural dip in our internal clock, and delaying caffeine simply risks shifting its consumption too late in the day, which may then impair sleep quality.

the sources

1. 1NIH Office of Dietary Supplements 2026
2. 2Manson JE et al. 2019
3. 3Bhatt DL et al. 2019
4. 4Khan SU, Lone AN, Khan MS, et al. 2021
5. 5Liao Y, Xie B, Zhang H, et al. 2019
6. 6hubermanprotocols.com (fan reference guide)