James PT, Ali Z, Armitage AE, et al. - This study was carried out to examine the latest evidence on how malnutrition across all its forms (under- and overnutrition and micronutrient status) may influence both susceptibilities to, and progression of, COVID-19. Information on 13 nutrition-related components and their potential interactions with COVID-19 were synthesized: overweight, obesity, and diabetes; protein-energy malnutrition; anemia; vitamins A, C, D, and E; PUFAs; iron; selenium; zinc; antioxidants; and nutritional support. In this study, 2,732 articles from PubMed and EMBASE across 13 searches, 4,164 articles from the preprint servers, and 433 trials were returned. There is very limited data that high-dose supplements of micronutrients will either prevent severe disease or speed up recovery. Nevertheless, outcomes of clinical trials are eagerly awaited. Public health strategies to reduce micronutrient deficiencies and undernutrition remain of critical importance, given the known impacts of all forms of malnutrition on the immune system. There is significant data that prevention of obesity and type 2 diabetes will decrease the risk of serious COVID-19 outcomes.