Imagine someone hauling two sacks up a hill. One is stuffed with sugar the body can't process. The other is filled with the years the body has lived through faster than the calendar says. If both sacks are light, the climb is easy. But if both are packed to the brim, the person doesn't just fall with one disease: they go down with several at once.
Doctors have found a way to weigh both sacks using a single blood test. The first sack is the TyG index. It shows how well the body copes with sugar. The second sack is biological age. It's estimated from three substances in the blood: creatinine, glucose, and C-reactive protein. These are measured in any clinic, but together they can tell you whether the body is aging faster than the years go by.
Scientists followed 8,767 people in China for nine years. One in ten of them developed two heart conditions at once, such as a heart attack and a stroke. In people carrying two heavy sacks, this outcome occurred 2.37 times more often than in those traveling light. Then the scientists tried tying both sacks together with one rope: they multiplied the TyG index by biological age. The result was a single combined measure. It did help predict disease, but no better than the two separate ones. So they suggest using it as a quick way to spot someone at risk, not as a replacement for standard tests.
Biological age by the Light-BA method uses just three biomarkers that are routinely measured in an ordinary clinic: creatinine, glucose, and C-reactive protein. This makes aging assessment accessible in virtually any laboratory.
The idea of measuring biological age and its link to disease echoes the film 'In Time' (2011), where people have built-in clocks counting down their lifespan. In reality, biological age can be estimated from a blood test, and it predicts the risk of multiple diseases.
Not published on arXiv. Here are its page, the PDF and the formalization: you can check it yourself, not only read our account.