Researchers in Ireland showed that a dietary supplement made from baker’s yeast boosted the body’s ability to fight cancer and slowed tumour growth in obese mice. 

Obesity weakens the immune system, hindering cancer immunotherapy. Even after weight loss, some immune issues persist, prompting researchers to seek safe ways to strengthen the immune response. 

Scientists from Trinity College Dublin (TCD) and University College Dublin (UCD), both EARA members, investigated whether beta-glucan, a natural fibre found in baker’s yeast with reported health benefits, could restore the immune response against cancer. 

Mice were fed a standard diet or a high-fat diet leading to obesity, with or without supplementation with yeast beta-glucan for four to twelve weeks. They induced colorectal, skin, and breast cancer in the animals and found the supplement reprogrammed early-stage immune cell development in the bone marrow, restoring obese mice’s ability to respond to tumours as if they were not obese.  

Frederick Sheedy, from TCD and lead author of the study published in Cell Reports, said: “Ultimately, a simple dietary supplement could help boost the immune system’s cancer fighting ability, complementing existing treatments such as chemotherapy and immunotherapy, with the potential to improve vaccine responses and resistance to infection.”