A rapid evidence review was published in June 2020, concluding that there is currently no evidence to support the use of vitamin D supplements to reduce the risk or severity of COVID-19. This review was followed by a second review in December 2020 which concluded that the evidence does not support vitamin D supplementation to prevent acute respiratory tract infections.
Following these reviews there is currently no evidence to suggest that supplementing vitamin D through fortified bread would reduce the risk or severity of COVID-19. However, companies are free to fortify certain products with vitamin D and already do so for several foods including many fats and spread, breakfast cereals, and some powdered milk.
Public Health England (PHE) have re-issued advice on vitamin D supplementation, advising that people who do not go outdoors often should consider taking a daily supplement containing 10 micrograms of vitamin D to prevent deficiency. The Government has also announced that over two and a half million vulnerable people across England will be offered free vitamin D supplements for the winter. However, this advice is not about reducing the risk of COVID-19 or mitigating its effects; vitamin D is needed to keep bones and muscles healthy.
PHE is monitoring any new, high quality evidence on nutrition and COVID-19 and is seeking further advice from the Scientific Advisory Committee on Nutrition as appropriate.