In biological age clocks, the kind COSMOS used, skin is one of the primary tissues researchers use to validate them. Epigenetic methylation patterns in skin cells are among the most studied markers precisely because skin is accessible and responds visibly to the same aging processes the clocks are trying to measure from blood.
The COSMOS trial gives everyone the same pill and measures a whole-body average signal from blood samples. It can't tell you which vitamin drove the effect or where in the body it's acting. It's a limitation of what a broad systemic intervention can tell you. The more targeted work is happening at the tissue level.
In skin specifically, L'Oréal and UC San Diego looked at 1,000+ subjects in 2024 and found that bacterial diversity in the skin microbiome correlates directly with both chronological age and wrinkle depth. They're building these as actual measurable aging biomarkers. Unilever's 2025 study also showed that people whose facial microbiome had higher Acinetobacter and lower Staphylococcus aureus were read as biologically 5–7 years younger. Many other companies are also researching biomarkers for skin anti-aging, and now the longevity trend is being seen in the food industry as well.
Microbiome as a modifiable aging clock is where the real specificity is starting to come from. I work in this space, and we recently mapped where this research is heading. We also did a session exploring the underlying science if you want to go deeper: https://greyb.com/resources/skin-microbiome-beauty/
When writing about complex topics, it gets tough to get below grade 11. Sometimes, it's the complex terms that cannot be replaced. Has anyone tried the Hemingway app? How do you solve this challenge?
By comparing GPT’s responses to global survey data from 65 countries, the authors show that GPT’s psychology most closely mirrors people from WEIRD societies (Western, Educated, Industrialized, Rich, and Democratic). In fact, the further a country is from the U.S. culturally, the less GPT behaves like its population.
Though it's easy to dismiss as science fiction, this timeline paints a chillingly detailed picture of a potential AGI takeoff. The idea that AI could surpass human capabilities in research and development, and the fact that it will create an arms race between global powers, is unsettling. The risks—AI misuse, security breaches, and societal disruption—are very real, even if the exact timeline might be too optimistic.
But the real concern lies in what happens if we’re wrong and AGI does surpass us. If AI accelerates progress so fast that humans can no longer meaningfully contribute, where does that leave us?
The COSMOS trial gives everyone the same pill and measures a whole-body average signal from blood samples. It can't tell you which vitamin drove the effect or where in the body it's acting. It's a limitation of what a broad systemic intervention can tell you. The more targeted work is happening at the tissue level.
In skin specifically, L'Oréal and UC San Diego looked at 1,000+ subjects in 2024 and found that bacterial diversity in the skin microbiome correlates directly with both chronological age and wrinkle depth. They're building these as actual measurable aging biomarkers. Unilever's 2025 study also showed that people whose facial microbiome had higher Acinetobacter and lower Staphylococcus aureus were read as biologically 5–7 years younger. Many other companies are also researching biomarkers for skin anti-aging, and now the longevity trend is being seen in the food industry as well.
Microbiome as a modifiable aging clock is where the real specificity is starting to come from. I work in this space, and we recently mapped where this research is heading. We also did a session exploring the underlying science if you want to go deeper: https://greyb.com/resources/skin-microbiome-beauty/
L'Oréal Study: https://www.frontiersin.org/journals/aging/articles/10.3389/... Unilever Study: https://academic.oup.com/bjd/article/193/Supplement_2/ii24/8...