Arginine’s Role in Combatting Cancer and Viral Infections

Recent research from Rockefeller University suggests a common amino acid, arginine, found in protein-rich foods and supplements, may play a significant role in defending against cancer and viral infections. The study highlights the impact of low arginine levels on the immune system’s ability to detect and respond to threats.

Arginine’s Function in Immune Defense

Sohail Tavazoie, leading the Elizabeth and Vincent Meyer Laboratory of Systems Cancer Biology at Rockefeller University, explained that arginine shortages in the body can hinder the production of MHC-1 proteins. These proteins are crucial for the immune system to recognize abnormal proteins from viruses and cancer cells, enabling their detection and destruction.

Arginine levels naturally decrease with age. It is common for cancers to display low arginine levels, and viruses often reduce arginine where they infect. Supplementing with arginine has shown promise in addressing these deficiencies, helping to lessen the severity of flu and COVID-19. In experiments with mice, even doses administered 24 hours post-infection improved outcomes.

Impact on Gene Expression and Protein Production

Arginine is vital for protein synthesis in cells, affecting a range of biological functions. Previously, low arginine has been associated with several diseases, such as colon cancer. Tavazoie’s team investigated further, finding that arginine deprivation can cause colon cancer cells to accumulate mutations. The team explored the impact of arginine on gene expression, particularly focusing on the production of MHC-1 proteins.

During studies using disease models like colon cancer and SARS-CoV-2, the team discovered that 414 proteins appeared at low levels when arginine was limited. Notably, the production of MHC-1 proteins, crucial for immune response, was severely affected by insufficient arginine.

Dietary Influence on Health Outcomes

Experiments in mice revealed that diets high in arginine resulted in fewer colon tumors and milder viral infections. Conversely, diets deficient in arginine worsened conditions such as flu, COVID-19, and tumor progression. The findings, published in the journal Cell, indicate that an arginine-deficient diet might contribute to poor health outcomes, though further research and clinical trials are necessary.

Tavazoie suggests that the age-related decline in arginine could partly explain the increased risk of colon cancer and more severe reactions to flu and COVID-19 in older individuals. His team plans to test whether arginine supplementation may improve outcomes for individuals at high risk for severe flu infections.

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