[Ragib_Zaman]

I highly recommend watching this video:

https://youtu.be/Kvh4D_osFXs

Sunlight gives us vitamin D and nitric oxide (which improves blood flow and reduces hypertension). Vitamin D is crucial for the functioning of our immune systems, and the 1000IU dosage of many supplements is laughably small. A light skinned person in a singlet standing outside at noon for 30 minutes will produce between 10,000IU and 20,000IU in their skin. I would recommend supplementing 5,000IU vitamin D while also getting some exposure in the morning or afternoon (but avoiding the sun when it is high in the sky).

[lhl]

The amount of UV exposure you get will differ significantly based on your latitude and time of year (and your skin type and weather of course). If anyone is serious enough to look into optimizing their sunlight exposure, I'd recommend playing around with these calculators to get an idea of what exposure is effective for you: https://fastrt.nilu.no/README_VitD_quartMEDandMED_v2.html

[NiceWayToDoIT]

Recently there was article/paper on HN about specific UV light wavelength from LED diodes that can produce very good response without daylight, creating significant amount of vitamin D.

https://www.nature.com/articles/s41598-017-11362-2 "The 293 nm LED was best suited for evaluating its effectiveness for producing vitamin D in human skin due to the shorter exposure time"

I tried looking for that manufacturer/diode but it seems it is not commercially available.

By now we should be able to buy a cheap lamp at any store maybe it would save some lives.

[newsbinator]

You really shouldn't recommend possibly-dangerous dosages of Vitamin D.

https://news.ycombinator.com/item?id=24738558

[AstralStorm]

Different place. Skin is big area and the vitamin gets relatively slowly transported to liver for storage. On the other hand, eaten D3 is absorbed very quickly with a fatty meal and you could obviously damage your liver with it.

EPIC series of studies suggests dosage of 2000-3000 IU for all cause lowest mortality. (Europe, regardless of diet. Caucasian.)

[Markoff]

that is really bad joke

pretty much whole Europe and whole India is vitamin D deficient, if you check actual studies, so no, unless you spend whole day naked in sun you won't get anywhere close to sufficient amount

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6060930/#:~:tex....

[mixmastamyk]

> but avoiding the sun when it is high in the sky

This is bad advice at high latitudes or in winter time. In those situations the highest sun should be sought.

[bagacrap]

this is great advice for the summer, but doesn't work so well in the winter, when the UV index is a small fraction of summer values and air temps are not conducive to skin exposure.