Cease the consumption of caffeinated beverages 8 to 10 hours before bedtime to preserve the quality and phases of deep sleep.

noli's read

This advice is particularly solid and aligns directly with the most recent scientific data. A 2023 meta-analysis published by Gardiner et al. in the journal *Sleep Medicine Reviews* (analyzing 24 studies) confirms that caffeine consumption reduces the duration and proportion of deep sleep. To avoid any reduction in rest time, researchers calculated that a standard cup of coffee should be consumed at least 8.8 hours before bedtime. Randomized clinical trials, such as the one by Drake et al., support this idea by showing significant sleep disturbances even 6 hours before sleep. Although Huberman's assertion is scientifically accurate for an average, it is worth noting that individual sensitivity and the rate of caffeine metabolism vary from person to person. The 8 to 10-hour window therefore proves to be an excellent general guideline to be customized according to one's own profile.

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)