Direct solar exposure of a large part of the body is far more effective than oral supplementation for raising vitamin D levels, although its effectiveness depends drastically on individual and geographical factors.

noli's read

The community largely agrees that cutaneous vitamin D production is a complex process influenced by latitude, skin pigmentation, and time of day, making personal experience difficult to generalize. Scientifically, it is well established (meta-analysis, Endocrine Society) that UVB exposure is the primary natural source, but it is limited by melanin type and the position of the sun (zenith angle), confirming comments on the ineffectiveness of morning sun or sun at northern latitudes. Oral supplementation (RCT) remains a reliable and measurable method for correcting deficiencies, particularly where sunlight is insufficient for a large part of the year. The idea that the sun is “better” is partially true physiologically, but obscures the risk of skin damage (carcinoma) often emphasized by health authorities. Finally, the personal experiences reported in the thread illustrate the genetic variability of cutaneous synthesis, a point supported by observational research. The forum converges toward a nuanced approach, recognizing that both methods have their limitations and their utility depending on one’s living context.

the sources

1. 1NIH Office of Dietary Supplements 2026
2. 2Manson JE et al. 2019
3. 3r/Supplements