Research

Hormonal

Sensible sun exposure produces vitamin D3 in the skin, which is metabolized into 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D, regulating calcium/phosphate metabolism and influencing chronic disease risk (autoimmune, cancer, cardiovascular, infectious, schizophrenia, type 2 diabetes).

Get sensible sun exposure to support your vitamin D levels, especially if you live at higher latitudes, have darker skin, or are older. The body regulates production to prevent toxicity, so you don't need to worry about overdose from the sun. If you cannot get enough sun, consider food fortification or supplements as part of a three-part strategy.

GoodSupportsHIGH confidence
Sun induced vitamin D synthesis is greatly influenced by season, time of day, latitude, altitude, air pollution, skin pigmentation, sunscreen use, passing through glass and plastic, and aging. vitamin D is metabolized sequentially in the liver and kidneys into 25-hydroxyvitamin D which is a major circulating form and 1,25-dihydroxyvitamin D which is the biologically active form respectively. 1,25-dihydroxyvitamin D plays an important role in regulating calcium and phosphate metabolism for maintenance of metabolic functions and for skeletal health. As a result 1,25-dihydroxyvitamin D influences a large number of biologic pathways which may help explain association studies relating vitamin D deficiency and living at higher latitudes with increased risk for many chronic diseases including autoimmune diseases, some cancers, cardiovascular disease, infectious disease, schizophrenia and type 2 diabetes.
Matthias G. Wacker et al. · Dermato-Endocrinology · 2013

Why this rating

The paper is a comprehensive review citing numerous association studies and historical clinical observations, though it acknowledges the distinction between association and causation for chronic diseases.

Source

Sunlight and Vitamin D

Matthias G. Wacker et al. · Dermato-Endocrinology · 2013

DOI 10.4161/derm.24494

narrative_reviewCited 1,128×
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DOI resolved against Crossref · corpus check 2026-06-10

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