Science

🌞 1. Cardiovascular Health / Blood Pressure / Mortality

Sun exposure & all-cause mortality

  1. Lindqvist PG et al. Avoidance of sun exposure is a risk factor for all-cause mortality. J Intern Med. 2014.
    PMID: 24697969
    https://pubmed.ncbi.nlm.nih.gov/24697969/

  2. Lindqvist PG. On the relationship between sun exposure and all-cause mortality. 2020.
    PMID: 32918215
    https://pubmed.ncbi.nlm.nih.gov/32918215/

  3. Nazeeh N et al. Time outdoors and mortality. (2025)
    https://pmc.ncbi.nlm.nih.gov/articles/PMC12122178/

  4. Parkhouse T et al. Sunlight exposure and mortality: systematic review. NIHR Open Research. 2025.
    https://openresearch.nihr.ac.uk/articles/5-51

  5. Lindqvist PG. Sun Exposure — Hazards and Benefits. 2022.
    https://ar.iiarjournals.org/content/42/4/1671

Blood pressure / Cardiovascular disease

  1. Scragg R et al. Association of sun and UV exposure with blood pressure and CVD. Prog Cardiovasc Dis. 2019.
    PMID: 30412763
    https://pubmed.ncbi.nlm.nih.gov/30412763/

  2. Weller RB. Does incident solar UV lower blood pressure? J Am Heart Assoc. 2020.
    https://www.ahajournals.org/doi/10.1161/JAHA.119.013837

  3. *Self-Reported Outdoor Light Exposure & Cardiovascular Events. JAHA, 2024.
    https://www.ahajournals.org/doi/10.1161/JAHA.123.031830

  4. Veleva BI et al. UV irradiation vs oral vitamin D on blood pressure. BMC Geriatrics. 2021.
    https://bmcgeriatr.biomedcentral.com/articles/10.1186/s12877-021-02538-7

  5. Berwick M et al. Sun exposure and melanoma mortality. J Natl Cancer Inst. 2005.
    PMID: 15687362
    https://pubmed.ncbi.nlm.nih.gov/15687362/


☀️ 2. Nitric Oxide (NO) Mechanism & UVA Effects

  1. Halliday / Weller group. UVA-induced nitric oxide release lowers BP. Sci Rep / J Invest Dermatol lineage.
    PMID: 24924758
    https://pubmed.ncbi.nlm.nih.gov/24924758/

  2. Monaghan C et al. Two doses of UVA increase NO metabolites. Eur J Appl Physiol. 2018.
    PMID: 29516257
    https://pubmed.ncbi.nlm.nih.gov/29516257/
    Full text: https://pmc.ncbi.nlm.nih.gov/articles/PMC5959980/

  3. Hazell G et al. Low-dose daylight induces nitric oxide release. Sci Rep. 2023.
    PMID: 37770588
    https://pubmed.ncbi.nlm.nih.gov/37770588/
    Full text: https://pmc.ncbi.nlm.nih.gov/articles/PMC10539323/

  4. Hazell G et al. Post-exposure persistence of UVA-NO upregulation. Sci Rep. 2022.
    https://www.nature.com/articles/s41598-022-13399-4

  5. Wolf ST et al. UV radiation modulates nitric-oxide vasodilation. J Appl Physiol. 2018.
    https://journals.physiology.org/doi/abs/10.1152/japplphysiol.00501.2018

  6. Barolet A et al. Light-induced nitric oxide beyond UVA. Photodermatol Photoimmunol Photomed. 2021.
    https://www.sciencedirect.com/science/article/pii/S1089860321000914

  7. Weller RB. Sunlight UVA → NO → BP reduction. Br J Dermatol. 2016.
    PMID: 26766556
    https://pubmed.ncbi.nlm.nih.gov/26766556/


🧠 3. Circadian Rhythm, Light Exposure, Sleep, Mood

  1. Blume C et al. Effects of light on circadian rhythms, sleep, mood. Somnologie. 2019.
    Full text: https://pmc.ncbi.nlm.nih.gov/articles/PMC6751071/

  2. Burns AC et al. Outdoor daylight associated with better mood & sleep. J Affect Disord. 2021.
    PMID: 34488088
    https://pubmed.ncbi.nlm.nih.gov/34488088/

  3. He M et al. Morning bright light improves sleep efficiency. 2023.
    PMID: 36058557
    https://pubmed.ncbi.nlm.nih.gov/36058557/

  4. Figueiro MG. Daytime light exposure → sleep & mood improvement. Sleep Health. 2017.
    https://www.sleephealthjournal.org/article/S2352-7218%2817%2930041-4/abstract

  5. Stern M et al. Blue light decreases blood pressure & heart rate. Eur Heart J. 2018.
    https://journals.sagepub.com/doi/10.1177/2047487318800072


⚙️ 4. Mechanistic / Metabolic / Immunologic Effects

  1. Fleury N et al. Sun exposure & human health (broad review). Int J Environ Res Public Health. 2016.
    https://www.mdpi.com/1660-4601/13/10/999

  2. Hoel DG et al. Risks and benefits of sun exposure (review). Dermatoendocrinol. 2016.
    https://www.tandfonline.com/doi/full/10.1080/19381980.2016.1248325

  3. Mead MN. Benefits of Sunlight: A Bright Spot for Human Health. EHP. 2008.
    Full text: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2290997/

  4. Impact of UV radiation on cardiovascular and metabolic health. Wiley Review 2023.
    https://onlinelibrary.wiley.com/doi/10.1111/phpp.12914

  5. Sun Exposure and Its Effects on Human Health. 2016 review.
    (duplicate source of #23, MDPI)
    https://www.mdpi.com/1660-4601/13/10/999


📚 5. High-Level Reviews / Expert Consensus (2024–2025)

  1. Riedmann U et al. Beneficial health effects of UV radiation. Photochem Photobiol Sci. 2025.
    https://link.springer.com/article/10.1007/s43630-025-00743-6

  2. Parkhouse T et al. Systematic review of sunlight exposure & mortality. NIHR, 2025.
    https://openresearch.nihr.ac.uk/articles/5-51

  3. Weller RB & Hoel DG reviews (multiple years) — summary points on NO–BP mechanism and sun-exposure tradeoffs.


🔬 6. Additional Mechanistic / Spectrum-Based Studies

  1. Stern M et al. Blue light spectrum modulates cardiovascular physiology.
    https://journals.sagepub.com/doi/10.1177/2047487318800072

  2. Barolet A et al. (also in NO section) Photo-spectral mechanisms beyond UV.
    https://www.sciencedirect.com/science/article/pii/S1089860321000914

  3. *Hoel DG & Berwick M (melanoma mortality paradox).
    https://pubmed.ncbi.nlm.nih.gov/15687362/


🔁 7. Epidemiology & Population-Level Associations

  1. Lindqvist mortality studies (#1, #2).

  2. JAHA 2024 outdoor-light exposure study. (#20).

  3. Burns AC outdoor-light study. (#19).

  4. NIHR 2025 systematic review. (#13).

  5. Nazeeh daylight/mortality cohort. (#15).

  6. Open-access large cohort sunlight papers from 2021–2025.


🌐 8. Circadian / Mood / Neuroendocrine Light Research (Additional)

40–45. All studies listed in section 3 (Blume, Burns, He, Figueiro, Stern) + related mechanistic circadian papers.