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SunlightEvidence & Dosage

UV, vitamin D, nitric oxide release, mood effects, the skin-cancer balance.

Evidence at a glance

Total studies
149
With abstract
40
Meta / Systematic / RCT
1
Highly cited
7
Publication years
2007–2026

Sunlight in the context of Methods

This topic is part of our "Methods" world. There you'll find methodology, evidence and the highest-impact levers — plus the order in which they sensibly build on each other.

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Top studies on Sunlight

Ranked by influential-citation count and publication year.

  1. Effects of artificial light at night on human health: A literature review of observational and experimental studies applied to exposure assessment.

    Chronobiol Int2015n=85review115 influential citations

    It has frequently been reported that exposure to artificial light at night (ALAN) may cause negative health effects, such as breast cancer, circadian phase disruption and sleep disorders. Here, we reviewed the literature assessing the…

  2. Time spent in outdoor light is associated with mood, sleep, and circadian rhythm-related outcomes: A cross-sectional and longitudinal study in over 400,000 UK Biobank participants.

    J Affect Disord2021n=502,000other90 influential citations

    BACKGROUND: Light has powerful effects on mood, sleep, and the circadian system. Humans evolved in an environment with a clear distinction between day and night, but our modern environments have blurred this distinction. Negative effects…

  3. Effects of visible light on mechanisms of skin photoaging.

    Photodermatol Photoimmunol Photomed2022review75 influential citations

    Human skin is not only affected by ultraviolet radiation but also by visible light wavelengths emitted by sunlight, electronic devices, and light emitting diodes. Similar to the ultraviolet radiation, visible light has been implicated in…

  4. Blue-light irradiation regulates proliferation and differentiation in human skin cells.

    The Journal of investigative dermatology201074 influential citations

    Sunlight influences the physiology of the human skin in beneficial as well as harmful ways, as has been shown for UV light. However, little is known about the effects of other wavelengths of solar irradiation. In this study we irradiated…

  5. The Complex Effects of Light on Metabolism in Humans.

    Nutrients2023review54 influential citations

    Light is an essential part of many life forms. The natural light-dark cycle has been the dominant stimulus for circadian rhythms throughout human evolution. Artificial light has restructured human activity and provided opportunities to…

  6. Light Modulation of Human Clocks, Wake, and Sleep.

    Clocks Sleep2019Study46 influential citations

    Light, through its non-imaging forming effects, plays a dominant role on a myriad of physiological functions, including the human sleep-wake cycle. The non-image forming effects of light heavily rely on specific properties such as…

  7. Effects of light on biological functions and human sleep.

    Handb Clin Neurol2025review28 influential citations

    The nonvisual effects of light in humans are mainly conveyed by a subset of retinal ganglion cells that contain the pigment melanopsin which renders them intrinsically photosensitive (= intrinsically photosensitive retinal ganglion cells,…

  8. Sunlight-Driven Production of Hydroxyl Radical from Manganese Minerals

    Environmental Science & Technology20263 influential citations

    Manganese (Mn) minerals are abundant across Earth's surface and have recently been recognized as sunlight-active materials. Here, we report that Mn minerals exhibit unexpectedly high photochemical reactivity for the generation of reactive…

  9. C–H Activation-Based Multicomponent Polyannulations toward Fluorescent Heteroaromatic Polyelectrolytes for Sunlight-Driven Antibacterial Coatings

    Journal of the American Chemical Society20261 influential citations

    The development of facile and efficient synthetic methods for functional polyelectrolytes bearing charges on main chains is an important, yet challenging task. Herein, we develop a straightforward C-H activation-based multicomponent…

  10. Enhanced sunlight-driven photocatalytic removal of tetracycline via C=O-functionalized g-C3N4: band structure tuning and active site regulation

    Environmental Research20261 influential citations

    The photocatalytic performance of materials is primarily governed by their band structure, charge carrier transport, and active sites. This study introduces a surface modification strategy for graphitic carbon nitride…

Frequently asked

What dosage was studied?
• Artificial light at night exposure (Varied exposure characteristics; includes outdoor ALAN levels, indoor light intensity, individual lighting habits, bright nighttime light, and shorter wavelengths) • Self-reported time spent in outdoor daylight (Each additional 1 hour spent outdoors during the day) • Visible light wavelengths (blue, yellow, red, broad visible light) (not reported)
Which population does the evidence apply to?
Most studies investigated: unknown; healthy.
Are there safety considerations for Sunlight?
• Nighttime bright light suppresses melatonin. • Nighttime light increases sleep onset latency. • ALAN may contribute to circadian phase disruption. • Potential negative psychological, cardiovascular, and metabolic effects are noted.

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