Here’s the Open Letter on Vitamin D and Covid-19. Over 100 physicians, researchers, and other experts signed a statement asking that ALL Adults take:

* 10,000 IU of vitamin D3 every day for 2 to 3 weeks
* And then take 4,000 IU of vitamin D3 every day continuously (or at least until the pandemic is over)

However, the experts each stated how much vitamin D they themselves are taking daily, and some were taking as much as 10,000 IU per day. The only signatory who is not taking vitamin D is a researcher in Australia where they are now heading into the Summer season. He probably knows his vitamin D level, and gets plenty of sunshine on skin to make vitamin D.

I’ve read many studies on vitamin D, and as a result, I now take 20,000 IU daily. Given the 40 plus studies that show the benefits of Vitamin D against Covid-19, I prefer to take a higher than usual dose to obtain as much protection as possible. See these Studies on Vitamin D and Covid-19

Vitamins to take with Vitamin D, while you are well:
Vitamin C, 500 mg 2x/day
Vitamin K1 and K2
Selenium 200 micrograms/day
Zinc 30 mg/day
and a B-complex multivitamin

There is a study showing the benefits of high-dose vitamin D for persons who have Covid-19:

Rastogi, Ashu, et al. “Short term, high-dose vitamin D supplementation for COVID-19 disease: a randomised, placebo-controlled, study (SHADE study).” Postgraduate medical journal (2020). Study Link
— Covid-19 patients were given 60,000 IU vitamin D daily for 7 days; these patients were 3.0 times more likely to become negative for Covid-19 than patients not given vitamin D.

Some of the patients given 60,000 IU for 7 days still did not have optimum levels by the 7th day, so they were continued on the 60,000 IU per day dosing.

If I had Covid-19, I would immediately start taking 50,000 IU of vitamin D3 each day for 7 days, and then switch to 10,000 IU per day continuously.

I have a set of supplements that I recommend to friends and family if they have Covid-19:

Vitamin D (see above)
Vitamin C 1000 mg/day
Vitamin K1 and K2 (Life Extension “Super K”)
Selenium 200 micrograms/day
Zinc 30 to 50 mg/day
Quercetin 250 mg 2x/day
B-complex vitamins
Aspirin 325 mg/day
Melatonin 3 mg timed release (increase gradually to 9 mg) once a day about an hour before bed (causes sleepiness)
** Ivermectin, a prescription medication, if you can convince your doctor to prescribe it.

Further Reading:
* List of Vitamin D Covid-19 studies — good analysis
* FLCCC Alliance i-MASK protocol for prevention and treatment of Covid-19
* Dr. Paul Marik MATH+ Protocol for Covid-19 prevention and treatment