does vit D cause calcification of arteries?
according to one article, it could in some settings, not clear when, many other sources point out the benefits of vit d

Vitamin D in Vascular Calcification: A Double-Edged Sword?

#q
How much sun exposure is needed for vit D instead of supplements?

answer from https://www.healthline.com/nutrition/vitamin-d-from-sun#time-of-day

At noon, the sun is at its highest point, and its UVB rays are most intense. That means you need less time in the sun to make sufficient vitamin D (5Trusted Source).

Many studies also show that the body is most efficient at making vitamin D at noon (6Trusted Source, 7Trusted Source).

For example, in the UK, 13 minutes of midday sunlight exposure during summer three times per week is enough to maintain healthy levels among Caucasian adults (5Trusted Source).

Another study found that 30 minutes ttof midday summer sun exposure in Oslo, Norway was equivalent to consuming 10,000–20,000 IU of vitamin D (8Trusted Source).

The commonly recommended daily dose of vitamin D is 600 IU (15 mcg) (3).

Vitamin D is critical for brain health…