Tyrosine Linked to Reduced Male Lifespan in New Genetic Study

Higher Blood Tyrosine Linked to Shorter Life Expectancy in Men

Elevated blood concentrations of the amino acid tyrosine are tied to a reduced lifespan in men, according to research published in the journal Aging-US. The investigation examined health records and genetic information from more than 270,000 participants enrolled in the United Kingdom Biobank (UK Biobank).

The research team was led by Jie V. Zhao, Yitang Sun, Junmeng Zhang, and Kaixiong Ye from the University of Hong Kong and the University of Georgia. Their analysis estimated that higher circulating tyrosine levels could potentially reduce male life expectancy by nearly one year. Women in the cohort showed no statistically significant change in lifespan relative to tyrosine concentrations.

Genetic Analysis Points to Sex-Specific Lifespan Differences

Mendelian randomization (MR) analysis indicates that the link between elevated tyrosine and reduced male lifespan may go beyond a simple correlation. Mendelian randomization (MR) uses naturally occurring genetic variants as proxies for biological variables. Because genes are assigned at conception, this technique reduces confounding from lifestyle choices or existing diseases.

Initial observational screens in the cohort linked both phenylalanine and tyrosine to an increased mortality risk. When investigators accounted for related metabolic variables, tyrosine remained independently associated with earlier death in men. The data also confirmed that male participants generally maintained higher baseline levels of circulating tyrosine than female participants.

Biological Roles of Phenylalanine and Tyrosine in Human Metabolism

Tyrosine and phenylalanine function as essential molecular building blocks for protein synthesis while supporting key neurological pathways. The human body uses tyrosine to synthesize neurotransmitters, including dopamine, which regulates mood, motivation, and cognitive processing.

Both amino acids occur naturally in protein-rich whole foods, including meat, dairy, eggs, and legumes. Tyrosine is also sold independently as an over-the-counter dietary supplement marketed for focus, alertness, and mental performance under acute stress. Scientists have not yet established how sustained differences in circulating concentrations of these amino acids influence long-term biological aging.

Study Limitations and Practical Research Gaps

Current findings stem from genetic modeling and observational registry data rather than controlled clinical feeding trials. The investigators emphasized that the dataset does not establish whether dietary changes or supplemental amino acid intake directly alter human lifespan.

The researchers noted that substantially more work is required before these findings can inform clinical guidelines or dietary recommendations. Individuals with questions regarding their protein intake or amino acid supplementation should discuss their individual lab values and health history with a qualified clinician.