If you miss your morning natural light exposure, double the duration of exposure the following morning to compensate for this deficit and preserve your circadian rhythm.

noli's read

The importance of morning natural light exposure for regulating the internal clock and optimizing alertness is well-supported by science, notably via a randomized controlled trial (RCT) by Dewan et al. (2011). Nevertheless, the formula of precisely "doubling" the duration of exposure the next day to make up for the previous day's deficit is based on an empirical tip (expert opinion) rather than a strict biological law. Research in chronobiology, such as the controlled trial (RCT) by Chang et al. (2012), shows that the response of our circadian rhythm to the duration of light exposure is highly non-linear. Doubling the time spent outside will therefore not mathematically double the resetting effect nor retroactively erase the slight clock drift accumulated the day before. Extending exposure the following day remains, however, an excellent wellness habit to maximize overall light capture, especially on cloudy days.

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)