CATEGORY: HEALTHY AGING & LONGEVITY
Tyrosine is an amino acid — one of the building blocks of protein — that your body uses to make dopamine and other brain chemicals tied to focus and motivation. Because of that, it is widely sold in supplements marketed for mental performance. But a large new study found that men with higher blood levels of tyrosine tended to have a shorter life expectancy — by close to a year — raising fresh questions about a compound many people assume is simply good for the brain.1
What the Researchers Examined
The team analyzed health and genetic data from more than 270,000 people in the UK Biobank, a large long-term health database. They looked at blood levels of two related amino acids, phenylalanine and tyrosine, and how they related to lifespan. Importantly, they used a genetic method called Mendelian randomization, which uses inherited gene variants people are born with to test whether a factor likely influences an outcome rather than just traveling alongside it. That makes the link stronger than a simple observation — though, as with all such studies, it stops short of final proof.1
What They Found
At first, both amino acids appeared tied to a higher risk of earlier death. After closer analysis, only tyrosine held up, and only in men: genetic estimates suggested that higher tyrosine levels were associated with roughly a year less of life expectancy. There was no significant effect in women, even though the same analysis drew on all 270,000-plus participants. The researchers noted that men naturally tend to carry higher tyrosine levels than women, which may even be one thread in the long-standing gap between male and female lifespans.
Why Tyrosine Might Matter
The mechanism is not settled, but scientists have a couple of leads. Tyrosine is involved in insulin resistance — a condition in which the body’s cells stop responding well to the hormone insulin, which is linked to many diseases of aging. It also feeds the production of stress-response chemicals like adrenaline, and chronic activation of those pathways may affect men and women differently because of how they interact with sex hormones.
An Important Caveat About Supplements
This study did not test tyrosine supplements directly — it measured naturally occurring blood levels and genetics. So it does not prove that taking a tyrosine supplement shortens your life. What it does suggest is that more is not automatically better with this amino acid, and that the “brain booster” marketing may be getting ahead of the evidence. If you take tyrosine for focus or energy, this is a good reason to be thoughtful rather than alarmed.
Key Takeaways
- For men taking tyrosine supplements for focus or energy, the study is a reason for caution — its long-term effect on lifespan is unproven.
- You do not need tyrosine supplements to get this amino acid; your body makes it and obtains plenty from ordinary protein in food.
- The finding applied to men, not women, and reflects blood levels and genetics rather than tested supplement doses — so interpret it as a caution, not a cause for fear.
- Before starting or stopping any supplement, talk with your healthcare provider, especially if you have a metabolic condition such as insulin resistance or diabetes.
References
- Zhao JV, Sun Y, Zhang J, Ye K. The role of phenylalanine and tyrosine in longevity: a cohort and Mendelian randomization study. Aging (Albany NY). 2025 Oct 3;17(10):2500-2533. link