Researchers found that molecular aging is dynamic and highly individual. Even people born on the same day may show opposite changes in gene activity, while differences can also occur in metabolites—small molecules produced through the body’s chemical processes that are essential for health.

Genetic factors, environmental exposures, and daily biological rhythms may contribute to these variations. The findings, published September 3 in Science, could challenge the idea that aging can be accurately represented by a single biological-age score.

Instead, the researchers suggest that biological aging may be better understood as a collection of changing molecular processes, with different biological systems aging at different rates. This highlights the complexity of aging and the limitations of relying on a single number to measure an individual’s biological age.

Source: https://www.livescience.com/health/aging/aging-doesnt-look-the-same-for-everyone-at-the-molecular-level-its-individualized-and-context-dependent