Scientists from the University of Hong Kong and the University of Georgia discovered that higher levels of the amino acid tyrosine in men's blood are associated with shortened lifespans, based on an analysis of health data from over 270,000 people in the UK Biobank. Men with elevated tyrosine levels had nearly a year shaved off their expected lifespan compared to those with lower levels, while women showed no such correlation. The study suggests that excess tyrosine might disrupt insulin signaling and contribute to conditions like insulin resistance, which are linked to poorer health outcomes as people age.
Written by the local model on 2026-09-15,
using this article's own text rather than the other coverage of the
same event (that is the story summary below).
A brain-boosting nutrient may sharpen your mind but knock years off your life.
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nutrient → boost → life
Research suggests the popular supplement ingredient, widely touted for improving focus and cognitive performance, may have a surprising downside when it comes to longevity.
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it → suggest → longevity
Scientists found that men with higher levels of the substance in their blood tended to have shorter lifespans — but women don’t appear to pay the same price.
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women → find → price
In the study, scientists from the University of Hong Kong and the University of Georgia analyzed health and genetic information from more than 270,000 people in the UK Biobank.
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scientists → analyze → Biobank
The researchers were focusing on two amino acids — phenylalanine and tyrosine — and whether they might play a role in aging.
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they → focus → aging
Both are essential building blocks for proteins, but tyrosine also helps the body make dopamine, adrenaline and other brain chemicals involved in mood, focus and stress response.
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body → help → response
Phenylalanine, meanwhile, is converted into tyrosine in the body.
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Phenylalanine → convert → body
Both amino acids occur naturally in protein-packed foods and are also commonly found in dietary supplements.
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acids → occur → supplements
To investigate whether the nutrients play a role in longevity, the researchers first looked at participants’ blood levels and compared them with their mortality and predicted lifespan.
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researchers → investigate → mortality
They then used a genetic testing method called Mendelian randomization, which involves looking at natural genetic differences between people to help determine whether one factor might actually cause another.
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factor → use → another
The team found that men with more tyrosine in their blood appeared to have shorter lifespans — with elevated levels associated with nearly a year shaved off their lives.
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levels → find → lives
Women, however, didn’t appear to have the same link.
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Women → appear → link
“Phenylalanine showed no association with lifespan in either men or women after controlling for tyrosine,” the study authors wrote.
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authors → show → tyrosine
Researchers don’t yet fully understand why higher tyrosine levels might be linked to shorter lifespans in men, but they have a few ideas.
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they → understand → ideas
One involves insulin resistance, a condition in which the body’s cells become less responsive to insulin, the hormone that helps regulate blood sugar.
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that → involve → sugar
Tyrosine plays an important role in the signaling process that allows insulin to tell cells to take up sugar from the bloodstream.
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insulin → play → bloodstream
While the amino acid is essential for normal cellular function, researchers have suggested that having too much tyrosine circulating in the blood could potentially disrupt that process.
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having → suggest → process
Insulin resistance is associated with a range of health problems that become more common with age — including neurodegenerative diseases, high blood pressure, cardiovascular disease and Type 2 diabetes — all of which can affect longevity.
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all → associate → longevity
Tyrosine may also play a role through the brain chemicals it helps produce, which are involved in mood and stress.
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which → play → mood
The researchers suggested that differences in these chemicals between the sexes could help explain why the link to shorter lifespan appeared in men but not women.
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link → suggest → men
Taking things a step further, they theorized that tyrosine could play some role in the well-documented longevity gap between men and women.
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tyrosine → take → men
However, they stressed that their study doesn’t prove the amino acid is responsible for the difference in average lifespan.
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acid → stress → lifespan
While notable, the findings don’t mean you should dump your supplements down the drain.
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you → mean → drain
The researchers didn’t directly test products that contain tyrosine, and there’s no proof that taking them will shorten your life.
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taking → test → life
After all, other research suggests that tyrosine has real benefits for mental focus, improving memory and boosting cognitive function under stress.
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tyrosine → suggest → stress
Instead, the study authors suggested that people with unusually high blood concentrations of tyrosine might potentially benefit from dietary changes aimed at lowering those levels.
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people → suggest → levels
Tyrosine-rich foods include chicken, turkey, beef, lamb, fish, hard cheeses, eggs, sesame seeds, soybeans and nuts.
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foods → include → chicken
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