Study finds high-fat diets help cancer cells 'hide' from immune system

It has been well established by this point that high-fat diets are linked to an increased risk of developing colon cancer, but how the two go together has remained unclear. That changes with a new study from researchers with MIT, Harvard Medical School, and Cold Spring Harbor Laboratory. At least when it comes to mice, a high-fat diet 'hides' cancer cells from the immune system.

Immune cells monitor the body for abnormal cells that need to be destroyed, helping prevent the development of various diseases and other health issues. Some immune cells work by looking for what the researchers call 'tags' on cells, ones that help them tell whether a cell is normal and healthy or abnormal.

In the case of intestinal cells, the study found that a high-fat diet suppressed the 'tag' called MHC-II, which triggers the immune cells to destroy old or potentially pre-cancerous cells before they can become a big problem. Abnormal cells with suppressed 'tags' caused by a high-fat diet could evade the immune system's detection, potentially allowing them to remain and grow into a cancerous tumor.

In addition, the study found that eating a high-fat diet also caused a change in gut bacteria, increasing levels of bacteria that can increase MHC-II 'tags.' This change may help the immune system find and destroy the abnormal cells. This finding may pave the way for future cancer treatments that, among other things, change the body's microbiome to help purge cancer cells.

This is the latest study detailing how diet composition can have a big impact on the body and how it functions. A recent study, for example, detailed how fructose changes intestinal cells in a way that promotes weight gain and obesity. Diet likewise influences gut bacteria, which also plays a big role in promoting health.