A newly published study in Aging-US on June 15, 2026, examines the potentially adverse effects of tyrosine on men’s long-term health. Tyrosine, often promoted for enhancing focus and brain performance, may surprisingly link to a shorter lifespan in men. The study indicates the importance of understanding amino acids like tyrosine in human health.
Why Tyrosine Matters
Tyrosine is a crucial amino acid in the body, acting as a building block of proteins. It supports essential processes like tissue repair and enzyme production. It also plays a vital role in regulating metabolism and brain activity. Found in foods such as meat, fish, eggs, and dairy, tyrosine is available as a supplement claimed to enhance concentration, energy, and cognitive function. Its influence on brain activity stems from its role in producing neurotransmitters such as dopamine, norepinephrine, and epinephrine, which affect mood, attention, motivation, and stress response.
What the Study Looked At
Researchers studied health and genetic data from over 270,000 U.K. Biobank participants to determine the impact of amino acids on lifespan. Led by Jie V. Zhao, Yitang Sun, Junmeng Zhang, and Kaixiong Ye from the University of Hong Kong and the University of Georgia, the team employed dual methods. They examined observed correlations between amino acid levels and mortality and used Mendelian randomization to explore potential causal relationships.
What They Found
Initially, both phenylalanine and tyrosine seemed linked to increased mortality risk. However, only tyrosine consistently correlated with lifespan after further analysis. Men with elevated tyrosine levels had shorter life expectancies, with genetic estimates suggesting nearly a year of reduced lifespan. No significant association was found in women. Researchers noted that men generally have higher tyrosine levels than women, which might contribute to lifespan disparities. Phenylalanine showed no lifespan association once accounting for tyrosine.
What Could Explain the Link
The study doesn’t pinpoint a singular cause but highlights possible biological pathways. One involves insulin resistance, where cells respond less effectively to insulin, linking to age-related diseases like type 2 diabetes, cardiovascular disease, and metabolic disorders. Tyrosine’s role in neurotransmitter production might also affect stress responses over time, impacting long-term health. Hormonal differences between sexes might explain the male-only observed effect.
What It Means for Supplements
Tyrosine is prevalent in products marketed for focus and alertness improvement, especially during stress. The study didn’t directly examine supplements or their lifespan effects, focusing on naturally occurring blood levels. Thus, while it doesn’t conclude that tyrosine supplements harm, it suggests considering elevated amino acid levels for long-term health. Researchers noted reducing overall protein intake might lower tyrosine levels, though its impact on healthy aging remains uncertain.
What Happens Next
The findings contribute to interest in brain function-related nutrients’ roles in aging. Additional studies are necessary to confirm the results in diverse populations and to understand the biological mechanisms better. Researchers aim to explore if dietary or lifestyle modifications can safely influence tyrosine levels.