00:00A supplement marketed for focus and brainpower may be quietly shortening men's lives.
00:04A massive study of more than 270,000 people has linked higher blood levels of the amino acid tyrosine to
00:12a shorter lifespan in men.
00:14Potentially cutting close to a year off male life expectancy, tyrosine occurs naturally in protein-rich foods.
00:20But it's also sold as a supplement for mental performance, which is what makes this finding so striking.
00:26Researchers combined observational data with genetic analysis and found no significant effect in women at all.
00:33The link held up even after accounting for phenylalanine, a related amino acid that showed no independent effect on lifespan
00:40for either sex.
00:41Scientists suspect insulin resistance could be one possible explanation.
00:45Since tyrosine plays a role in dopamine production and stress response, the findings are published in the journal Aging US.
00:52But researchers caution it's still too early to change your diet or supplement routine based on this alone.
00:59Disclosure. This video contains stock footage and content created or enhanced using AI-assisted tools.