The types of fats people eat may influence how well key immune cells survive, according to new mechanistic research published in Nature. Scientists report that dietary fats can alter the fat composition inside T cells, which are central players in the body’s immune response.
In experimental research examining lipid metabolism and immune cells, investigators found that diets with a lower ratio of polyunsaturated fatty acids (PUFAs) to monounsaturated fatty acids (MUFAs) produced T cells that were more resistant to a form of cell death triggered by oxidative damage. The work focuses on cellular mechanisms and does not establish specific dietary recommendations for people.
“Our immune system relies on T cells to manage the body's immune response,” said Di Yu, Ph.D., professor at the University of Queensland’s Frazer Institute and senior author of the study. “The kinds of fats you eat change the fat composition inside your T cells and those changes can make T cells either weaker or stronger in terms of immune protection.”
T cells are essential for recognizing pathogens and helping the body produce antibodies. Their survival and ability to multiply affect how effectively the immune system responds to infections and vaccines.
In the study, researchers examined how dietary fats influence a process called ferroptosis, a type of cell death that occurs when oxidized fats damage the outer membrane of cells. When certain fats accumulate in the membranes of T cells, the cells become more vulnerable to this oxidative damage.
The researchers found that altering the balance of fats in the diet changed the types of fats incorporated into T cells. Cells containing more monounsaturated fats appeared more resistant to oxidation-driven damage.
“When T cells are protected from this oxidation-induced cell death, specific T cells (called follicular helper T cells) become much better at assisting the body in producing antibodies, which could suggest enhanced vaccine protection,” Yu said.
Follicular helper T cells help B cells produce antibodies that target viruses and bacteria. In experimental models, the researchers found that protecting these immune cells from ferroptosis improved their ability to expand and support immune responses.
“Stronger, more resilient T cells are also better at multiplying and actively attacking tumours,” Yu said.
Although the findings highlight a potential connection between diet, lipid metabolism and immune cell resilience, the researchers emphasize that the optimal balance of dietary fats remains unclear.
Examples of foods rich in polyunsaturated fats include fatty fish and soybeans. Monounsaturated fats are found in foods such as olive oil and avocados. Most whole foods contain a mixture of different fats, and the study does not suggest eliminating any particular fat source.
“The ideal ratio of PUFA to MUFA foods in the diet is not yet known,” Yu said, adding that further research will be needed to understand how dietary fats influence immune function in people.
The findings add to a growing body of research showing that nutrition can influence the biology of immune cells through changes in lipid metabolism. Researchers say the work could eventually inform strategies to support vaccine responses or improve cancer immunotherapy, but those applications remain speculative.
The research received support from multiple public research programs and institutional infrastructure grants. These include funding from the Australian National Health and Medical Research Council, the Medical Research Futures Fund, the National Natural Science Foundation of China and the Australian Government Research Training Program. The work also used research infrastructure supported by Bioplatforms Australia and the National Collaborative Research Infrastructure Strategy. Additional support came from university and research institute programs in Australia and China.