Aging clocks find different metabolic turning points by sex

A routine health check contains more than isolated numbers: body mass index, cholesterol, triglycerides and other measures can form a picture of how quickly the body is aging. Researchers in China used 172 commonly measured indicators to build separate clinical aging clocks for men and women, drawing on records from 104,208 adults aged 18–98 across three centers.

The pattern was not the same for everyone. Men showed a prominent metabolic transition between 35 and 45, involving body mass index, triglycerides and cholesterol. Women showed a later transition between 55 and 65, around menopause, with marked endocrine changes alongside worsening lipid profiles. The physiological differences between men and women generally narrowed in later life.

The team also examined what might sit behind the clock's signals. Glucose, lipids, uric acid and the tumor-related markers CEA and HE4 accumulated with age and were associated with faster physiological aging. In cell experiments, elevated levels of these circulating factors induced aging-related changes in vascular endothelial cells, suggesting they may contribute to aging rather than simply record it.

Some of those effects were not fixed in the experiments. Metformin alleviated high-glucose-induced endothelial aging in cells, while moving mice from a high-fat diet to a normal diet improved several liver aging-related features. Those results point to metabolic burden as a possible target, but they are not evidence that metformin or a diet change has been shown to slow aging in people.

So what changes in practice? The researchers propose that routinely collected clinical data could offer a scalable way to estimate physiological aging and identify sex-specific moments for closer attention. The study establishes a research framework, not a deployed medical tool: its human analysis maps associations, while the reversible effects come from cell and mouse experiments.