A person lies inside an MRI scanner while, nearby, tubes for blood and scissors for hair are being prepared. So begins the assembly of India's first atlas of healthy aging, for a country that will have 230 million elderly people by 2036.
Participants are being recruited strictly: 300 healthy people, 100 in each of three age groups, 19–35, 40–55, and 60–75 years. No chronic illnesses or long-term medication. Each gives blood, a lock of hair, and takes memory tests. From the hair, researchers will extract the stress hormone cortisol, which accumulates there like tree rings. Three centimeters of hair remember three months of a person's life.
Once all the data are collected by the end of 2026, doctors will be able to tell ordinary aging from the early signs of dementia in a specific patient. This will be the first Indian reference built on local residents, rather than borrowed from Western textbooks.
Hair cortisol offers a glimpse 3–4 months into the past: each centimeter of hair stores roughly 2–3 weeks of hormonal history. The three inches cut from participants correspond to one season of life.
Not published on arXiv. Here are its page, the PDF and the formalization: you can check it yourself, not only read our account.