Everyone should be taking a high dose vitamin d supplement right now. Get those serum levels right up for when winter kicks in.
In the morning with some fat is a good time. You can get ones suspended in oil with vit k2 in as well if you like a low fat brekkie.
Its been known for a long time vit d is very protective against respiratory infections and significantly lowers the risk of complications as well.
Look at Africa and parts of Asia, very low mortality rates from covid yet the mainstream media are trying to say its more dangerous for those demographics because it plays into their woke commie racial tensions agenda and its too cheap to make money off. It's vit D deficiency obviously, those with dark skin can't absorb enough in the british climate most of the year and so will have a worse reaction especially if they take in a high viral load from hospital or care work etc...
Not saying its the cure or anything because its not but take vit D 4000iu minimum throughout the winter months