Does vitamin d help people to cope with flu and cold?

Vitamin D supplementation is recommended and may be of some value with viral infections. Although not fully established, seems to benefit MS sufferers and maybe reduce severity in COVID-19. Would suggest obtaining through sunshine and/or oral intake up to 5,000 IU's daily. Aim for serum levels at 50-70 ng/ml, but would avoid higher goals.

No good data. One of my colleagues did a study in identical twins one got the Vit C and other placebo and could see no effect in kids. Do not know of similar trial with Vit D. You can go to pubmed.com and search for Vit D AND flu OR common cold and see the worlds' literature and read those articles you want.