A lactose-free diet could help reduce graft-versus-host disease

A recent study finds that lactose, the enzyme found in milk, can fuel a type of bacteria that promotes graft-versus-host disease in those who undergo a bone marrow transplant. In graft-versus-host disease, donated bone marrow cells attack the recipient’s cells. In the new research, scientists report that harmful Enterococcus bacteria grew more in the presence of lactose than in lactose-free environments. Mice with GVHD whose diets had been depleted of lactose had less growth of Enterococcus and the severity of their disease was also reduced, researchers found. They also observed that patients who lacked a form of a gene that didn’t allow them to absorb lactose properly had worse disease. The concept will still need to be validated in trials, but a diet free of lactose could be a non-antibiotic option for GVHD, the scientists suggest