42% of the US population has a vitamin D deficiency [0]. In the HN population, that number might even be higher (extrapolating my experience with tech workers and the hours they spend outside).

I would encourage most people here to have their Vitamin D levels checked and take supplements, especially in the winter months.

[0] https://pubmed.ncbi.nlm.nih.gov/21310306/

Most doctors I’ve met agreed with this.

Also certain diets could have other deficiencies, like in my case I almost never eat fish so I add omega3 (DHA).

I agree, if it's likely your deficient you should get tested and supplement as necessary. That's my point. It should be done as part of evidence based medicine and not a random thing you decide to do with no supporting evidence.

Ideally everyone should get periodic vitamin D level tests, and then adjust their diet, sun exposure, and supplementation accordingly. But unfortunately it's just not practical to test everyone. And also we know that a large fraction of the population is deficient, and that moderate supplement doses are generally safe. So routine supplementation is justified for most of us on an evidence based medicine basis.

There is some limited in vitro evidence for zinc as a treatment.

https://journals.plos.org/plospathogens/article?id=10.1371/j...

The evidence for vitamin D is much stronger including multiple randomized controlled trials.

https://vitamin-d-covid.shotwell.ca/

I have seen scientific evidence that Vit D supplimenting helps. In Spain its prescribed if you get covid. re: "unless you are deficient": you supliment to ensure you arent deficient, you are foolish to risk zinc or Vit D deficiency if you know you have covid. If you plan a fews days in bed you are (usually) not going to get much sun. It's foolish to risk deficiency of any vitamin while ill.

> First, there's no scientific basis for doing so.

"No scientific basis" doesn't necessarily mean "false", otherwise you create a world where everything not mandatory is forbidden. Many doctors do exist in this world; they're always totally confident even when they're wrong, and they will tell you to not do things unless it's the specific thing they want you to do.

"No scientific basis" means you look at the best scientific evidence we have today and make informed decisions based on it. You don't make stuff up with the hope that it's helpful.

>you're spending months in an overcast winter environment

I'd imagine this would include ~30-40% of Americans.

“ there's no scientific basis”

Theres no scientific basis for anything until a proper study is done. Doesn't mean it isn't true. And consider that estimates are as high as 50% of scientific papers’ results are false (especially in bio).

N.B.1: I'm a scientist in a government lab

N.B. 2: I’m not impugning science, just fellow scientists.

What's your point? When you make a medical decision it should be based on the best research done to date. Just because existing research doesn't mean something isn't true isn't a reason to do it.

> And consider that estimates are as high as 50% of scientific papers’ results are false (especially in bio).

Source?

Ioannidis JPA (2005) Why Most Published Research Findings Are False. PLoS Med 2(8): e124. https://doi.org/10.1371/journal.pmed.0020124

Where is the 50% number? Or are you linking to a random paper? (i.e. not the source for the claim)

Did you even read the paper? "Most" is >50%.

Nope. You don't invent numbers like that. A claim that includes a specific number needs an actual citation which includes the number.

"Most Research Findings Are False for Most Research Designs and for Most Fields" is a ridiculous claim. I don't know a single scientist who believes that. How many scientists have you spoken to in the bio field?

Do you have a substantiave criticism of the paper that I linked?