BENEFITS OF SUNLIGHT EXPOSURE (does sunscreen block vitamin D production?)
SUNLIGHT SYNCS CIRCADIAN RHYTHM
Early morning sunlight exposure calibrates your circadian rhythm and release of cortisol, serotonin, and melatonin.
This supports vibrant energy & mood during the day and restful sleep at night.
Sit by an east window, go for a walk, or spend at least 15 minutes outside each morning.
A full-spectrum vitamin D lamp can substitute on dark or cloudy days.
NOTE: Sunglasses block much of the light needed to sync your circadian rhythm.
SUNLIGHT SYNTHESIZES VITAMIN D
When exposed to UVB rays, cholesterol in the skin is converted to vitamin D.
Midday sun exposure to large skin areas for 15-30 minutes can provide your minimum daily need (more during winter, if live at northern latitudes, or if have dark/tanned skin).
BEYOND VITAMIN D
UV light activates several other beneficial compounds in the skin that promote:
immune regulation (substance P, CGRP, Treg cells, POMC, ACTH)
gene repair & UV protection (a-MSH)
stress relief & mood (endorphins)
TYPES OF UV RAYS
UVB = BURNS
tans, burns, vitamin D synthesis
surface level damage, skin cancer
cannot pass through glass
UVA = AGING
penetrates deeper into dermis layer of skin
DNA damage, aging, skin cancer
can pass through glass
SCREEN VS BLOCK
SCREEN
chemical barrier
absorbs/reduces UVB, not UVA
BLOCK
physical barrier
deflects both UVB and UVA
SHOULD I USE SUN PROTECTION?
There is a risk of skin damage from both UVB & UVA rays.
SPF use may be appropriate when UV levels are high (3+), but should be balanced with adequate unprotected exposure.
Some oxidative UV damage can be counteracted by consuming colorful, antioxidant-rich plant foods and healthy fats from olives & fatty fish.
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References
Jung, C. M., Khalsa, S. B., Scheer, F. A., Cajochen, C., Lockley, S. W., Czeisler, C. A., & Wright, K. P., Jr (2010). Acute effects of bright light exposure on cortisol levels. Journal of biological rhythms, 25(3), 208–216. https://doi.org/10.1177/0748730410368413
Moattari, C. R., & Granstein, R. D. (2021). Neuropeptides and neurohormones in immune, inflammatory and cellular responses to ultraviolet radiation. Acta Physiologica, 232(1), 1–22.
Mead M. N. (2008). Benefits of sunlight: a bright spot for human health. Environmental health perspectives, 116(4), A160–A167. https://doi.org/10.1289/ehp.116-a160
Ruiz-Ballesteros, A. I., Meza-Meza, M. R., Vizmanos-Lamotte, B., Parra-Rojas, I., & de la Cruz-Mosso, U. (2020). Association of Vitamin D Metabolism Gene Polymorphisms with Autoimmunity: Evidence in Population Genetic Studies. International Journal of Molecular Sciences, 21(24). https://doi-org.uws.idm.oclc.org/10.3390/ijms21249626
Jeon, SM., Shin, EA. Exploring vitamin D metabolism and function in cancer. Exp Mol Med 50, 1–14 (2018). https://doi.org/10.1038/s12276-018-0038-9
Carlberg, C., & Haq, A. (2018). The concept of the personal vitamin D response index. Journal of Steroid Biochemistry and Molecular Biology, 175, 12–17. https://doi-org.uws.idm.oclc.org/10.1016/j.jsbmb.2016.12.011
Lemke, D., Klement, R. J., Schweiger, F., Schweiger, B., & Spitz, J. (2021). Vitamin D Resistance as a Possible Cause of Autoimmune Diseases: A Hypothesis Confirmed by a Therapeutic High-Dose Vitamin D Protocol. Frontiers in Immunology, 12, 655739. https://doi-org.uws.idm.oclc.org/10.3389/fimmu.2021.655739
Saksa, N., Neme, A., Ryynänen, J., Uusitupa, M., de Mello, V. D. F., Voutilainen, S., Nurmi, T., Virtanen, J. K., Tuomainen, T.-P., & Carlberg, C. (2015). Dissecting high from low responders in a vitamin D3 intervention study. Journal of Steroid Biochemistry and Molecular Biology, 148, 275–282. https://doi-org.uws.idm.oclc.org/10.1016/j.jsbmb.2014.11.012
Wang, S., Wu, Y., Zuo, Z., Zhao, Y., & Wang, K. (2018). The effect of vitamin D supplementation on thyroid autoantibody levels in the treatment of autoimmune thyroiditis: a systematic review and a meta-analysis. Endocrine, 59(3), 499–505. https://doi-org.uws.idm.oclc.org/10.1007/s12020-018-1532-5
Hopefl, R., Ben-Eltriki, M., & Deb, S. (2022). Association Between Vitamin D Levels and Inflammatory Markers in COVID-19 Patients: A Meta-Analysis of Observational Studies. Journal of Pharmacy & Pharmaceutical Sciences : A Publication of the Canadian Society for Pharmaceutical Sciences, Societe Canadienne Des Sciences Pharmaceutiques, 25, 124–136. https://doi-org.uws.idm.oclc.org/10.18433/jpps32518
Penckofer, S., Ridosh, M., Adams, W., Grzesiak, M., Woo, J., Byrn, M., Kouba, J., Sheean, P., Kordish, C., Durazo-Arvizu, R., Wallis, D., Emanuele, M. A., & Halaris, A. (2022). Vitamin D Supplementation for the Treatment of Depressive Symptoms in Women with Type 2 Diabetes: A Randomized Clinical Trial. Journal of Diabetes Research, 2022, 4090807. https://doi-org.uws.idm.oclc.org/10.1155/2022/4090807
Li, B., Xu, Y., Zhang, X., Zhang, L., Wu, Y., Wang, X., & Zhu, C. (2022). The effect of vitamin D supplementation in treatment of children with autism spectrum disorder: a systematic review and meta-analysis of randomized controlled trials. Nutritional Neuroscience, 25(4), 835–845.
El Amrousy, D., Abdelhai, D., & Shawky, D. (2022). Vitamin D and nonalcoholic fatty liver disease in children: a randomized controlled clinical trial. European Journal of Pediatrics, 181(2), 579–586. https://doi-org.uws.idm.oclc.org/10.1007/s00431-021-04243-4
Guo, X., Liu, C., & Huang, Y. (2022). Efficacy and Safety of Vitamin D Adjuvant Therapy for Ulcerative Colitis: A Meta-Analysis. Computational and Mathematical Methods in Medicine, 2022, 6836942. https://doi-org.uws.idm.oclc.org/10.1155/2022/6836942
Ersahin, S. S., & Ersahin, A. (2022). Serum 25-hydroxyvitamin D correlates with endometrial HOXA10 mRNA expression. European Review for Medical and Pharmacological Sciences, 26(10), 3483–3486. https://doi-org.uws.idm.oclc.org/10.26355/eurrev_202205_28842
Gu, J.-C., Wu, Y.-G., Huang, W.-G., Fan, X.-J., Chen, X.-H., Zhou, B., Lin, Z.-J., & Feng, X.-L. (2022). Effect of vitamin D on oxidative stress and serum inflammatory factors in the patients with type 2 diabetes. Journal of Clinical Laboratory Analysis, 36(5), e24430. https://doi-org.uws.idm.oclc.org/10.1002/jcla.24430
Cheng, J., Meng, S., Lee, J., Kwak, H.-B., & Liu, Y. (2022). Effects of walking and sun exposure on bone density and balance in elderly with osteopenia. Journal of Bone and Mineral Metabolism, 1–7. https://doi-org.uws.idm.oclc.org/10.1007/s00774-022-01317-7
Lindqvist, P. G., Landin-Olsson, M., & Olsson, H. (2021). Low sun exposure habits is associated with a dose-dependent increased risk of hypertension: a report from the large MISS cohort. Photochemical & Photobiological Sciences, 20(2), 285–292. https://doi-org.uws.idm.oclc.org/10.1007/s43630-021-00017-x
Joh, H.-K., Hwang, S., Cho, B., Lim, C. S., & Jung, S.-E. (2020). Effect of sun exposure versus oral vitamin D supplementation on serum 25-hydroxyvitamin D concentrations in young adults: A randomized clinical trial. Clinical Nutrition, 39(3), 727–736. https://doi-org.uws.idm.oclc.org/10.1016/j.clnu.2019.03.021
Nebert DW, Wikvall K, Miller WL. 2013 Human cytochromes P450 in health and disease. Phil Trans R Soc B 368: 20120431. http://dx.doi.org/10.1098/rstb.2012.0431