Environmental light exposure and mealtime regularity: Implications for human health

ABSTRACT

Light exposure and mealtime act as cues to the human circadian rhythm, which subsequently regulates various physiological functions in the body. However, modernization alters lifestyles, with changes to social and work-related activities independent of the natural light–dark cycle. This review summarizes the role of light exposure and regular mealtime on bodily processes and, ultimately, metabolic health. Various aspects of light are reviewed, including the type of light (natural/artificial), intensity (lux), spectral composition, time of exposure (night/day), and exposure duration. Further, the possible relationship between light exposure and mealtime irregularity is discussed as a function affecting metabolic health. In essence, research evidence suggests that mealtime regularity and light exposure habits based on the natural occurring light–dark cycle are essential for metabolic health in relation to an aligned circadian rhythm.

KEYWORDS:

• Light
• mealtime
• metabolic health
• circadian rhythm
• clock

Acknowledgements

We would like to thank Chew Wan Ling for her helpful insights on the review topic.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the UCSI University Research Excellence & Innovation Grant under Grant REIG-FAS-2020/006.