The effects of light in children: A systematic review.

Light affects human health and behaviour. Research has demonstrated that children are more susceptible to the effects of light than adults, however this population remains underrepresented in the literature. This systematic review reports evidence of objectively measured light exposure on health and development outcomes in children (0–12 years old). Study (n = 59) outcomes were categorised into five thematic domains. Heterogeneity of light measurement and summarisation techniques were identified. Light's effects on melatonin and activity patterns were relatively robust, while research on sleep was sparse. Mixed findings suggest a protective effect of light on myopia, and vision improvements under cooler, brighter lighting. Increased light during the daytime was broadly associated with beneficial effects on social-emotional, cognitive, and physical health outcomes. Timing, colour, and intensity of light exposures were important in understanding health and developmental effects of light. Heterogeneity in light measurement methods limits comparability across studies and should be carefully considered. Greater understanding about the effects of light on children could inform novel approaches to support children's health, sleep, and development. • Reviews a rapidly emerging field of research into the effects of light for children's health and developmental outcomes. • Lighting exposure was linked to melatonin suppression and daily activity patterns, but sleep research remains sparse. • Increased daytime light was broadly associated with ophthalmological, psychological, and physical health outcomes. • Light measurement and summarisation methods are currently heterogenous across existing literature and research fields. [ABSTRACT FROM AUTHOR]