This isn’t a new article but is interesting. It offers some possible explanations as to how it might work for some and not others. It goes through some DNA mutations that are involved in mannose processing in the body and identifies some that may cause problems in metabolism. Mannose helps by halting bacterial infections especially urinary infections in some people but not all depending on their genes.
“Collectively, these studies underscore the variable phenotypic impact of disrupting mannose metabolism supplying different pathways and in different cells and tissues. It suggests that glycosylation load and metabolic flux must play critical roles in determining the outcome. Epigenetic phenomena may also make important contributions, but these have not been explored in these disorders .”