Sinclair, a genetics professor at Harvard Medical School, has conducted extensive research on the aging process. In his podcast Lifespan, he recently discussed the rate of nail growth as a potential marker of biological aging. His theory: the faster your nails grow, the younger your body is biologically. This is because rapid cell renewal points to a strong regenerative capacity – a sign of a young and healthy system.

As early as 1979, a study showed that the rate of nail growth decreases by about 0.5% per year after the age of 30. This means that as we age, this process slows down, indicating that our bodies produce fewer new, healthy cells over time.

But it’s not just nail growth that tells a story – their condition also plays a role. U.S. dermatologist Michelle Henry explains that as we get older, our bodies produce less keratin. This can cause nails to become more brittle and dry. Even changes like ridges or discoloration could point to underlying health issues.

The good news? A healthy lifestyle, including a balanced diet and proper nail care, can help keep your nails strong – and may even have a positive impact on your biological age.

So, how fast are your nails growing? It might be worth paying closer attention in the future.