Eine Subgruppenanalyse des Vital-Trials von Kahn et al. im BMJ 2022 zeigt durchaus Effekte bei Autoimmunerkrankungen:

Conclusions Vitamin D supplementation for five years, with or without omega 3 fatty acids, reduced autoimmune disease by 22%, while omega 3 fatty acid supplementation with or without vitamin D reduced the autoimmune disease rate by 15% (not statistically significant). Both treatment arms showed larger effects than the reference arm (vitamin D placebo and omega 3 fatty acid placebo).

Quelle: BMJ 2022; 376 doi: https://doi.org/10.1136/bmj-2021-066452 (Published 26 January 2022)