I’ve been taking vitamin D and zinc for over 2 years. So far no covid
My blood levels for vitamin D were last measured a 170 ng/ml. Very high. My doctor wants my under 120. In spite of the high levels, my wife's co-workers infected her in January 2022 and January 2023 and she shared it with me. Both cases were relatively mild with a 10 day active phase. The first (BA.1) had a very bad sore throat, malaise, fatigue, blood in urine, minor fever, one instance of dizziness, endless postnasal drip and runny nose. The second case was mostly postnasal drip and chest congestion. My SP02% overnight dropped to 86%, breaths per minute topped 22, temperature spiked to 102.5 on Jan 9th, then rapidly recovered. The RAT test line was very strong. Deep purple as soon as the fluid hit the line and well before it reached the control line.
The point is the vitamin D/zinc prevents severe disease, but it is not an invincible armor. It just keeps the acute viral phase of the disease in the minor leagues.
A couple weeks past the acute phase with a negative RAT, I still had significant postnasal drip and chest congestion. Mucinex helped in 4 hour "windows". I added sulforaphane to my morning supplements. The chest tightness went away and never returned.