According to new research from Rockefeller University, arginine, a common amino acid found in protein-rich foods and over-the-counter supplements, may have a crucial role in combating cancer and viral infections. The study reveals that low arginine levels inhibit cells from producing a protein essential for the immune system to detect cancer and viruses.
Research Findings
Sohail Tavazoie, leading Rockefeller University’s Elizabeth and Vincent Meyer Laboratory of Systems Cancer Biology, explained that low arginine levels are a characteristic of cancers and that viruses minimize arginine in infected tissues. Arginine levels also decline naturally with age.
Tavazoie stated, “We have found that these reduced arginine levels decrease our cells’ ability to produce MHC-1, a key protein that presents abnormal proteins from viruses or mutated cancer cells to our immune system.” This presentation is critical for identifying and eliminating threats.
Supplementing with dietary arginine was shown to address the deficiency caused by cancer or viruses. In research, it reduced flu and COVID-19 severity. Notably, influenza outcomes improved in mice even when arginine was administered 24 hours post-infection. The dosage used equated to about 10 grams per day, comparable to a few over-the-counter tablets.
Arginine and Immunity
Arginine, an amino acid produced by the body and present in protein-rich foods, assists cells in protein synthesis, serving many biological roles. Low arginine levels have been linked to diseases such as colon cancer.
Building on previous findings, Tavazoie’s team explored how arginine levels impact gene expression. Studying disease models like colon cancer, influenza, and SARS-CoV-2, researchers identified 414 proteins that were deficient when arginine was scarce. Though many aligned with known functions of arginine, the presence of three genes for MHC-1 production was particularly significant.
MHC-1 proteins, located on cell surfaces, display foreign or abnormal proteins to T cells, prompting an immune response. The study found that insufficient arginine caused ribosomes to stall, hindering MHC-1 production and reducing signals to the immune system.
Dietary Impact on Disease Risk
In mice, a diet rich in arginine resulted in fewer colon tumors and milder viral infections, whereas low-arginine diets worsened outcomes for flu, COVID-19, and tumor growth. Published in Cell, these findings suggest a dietary arginine deficiency might lead to poorer disease outcomes, though further studies and clinical trials are necessary.
Tavazoie indicated that the age-related decline in arginine “could also partially explain the age-associated risk of developing colon cancer,” along with increased severity of flu and COVID-19 in older adults. His team plans to test if arginine supplements could benefit flu patients at high risk of severe illness.
Reference: Tavazoie, S. F., et al. (2026). Dietary arginine drives codon-dependent MHC class I translation and improves immunity in colon tumorigenesis and respiratory viral infection. Cell. https://doi.org/10.1016/j.cell.2026.07.020.
Contact Newsweek editors about this story: Kara Dolman and Sam Wilson.