Telomeres don’t necessarily shorten as you age, normally the enzyme telomerase compensates for the shortening. Only if you live unhealthy (smoking, eating bad food, …) the telomerase can’t function properly, and telomeres will shorten.
See how Elizabeth Blackburn explains it: https://www.youtube.com/watch?v=-lNR1xZS5GY (part 3 of a lecture, but she starts with a summary of part 1 and 2 where she says what I said here).
Telomeres tend to shorten as you age whether you live a good life or not. Nowhere does Blackburn claim that they do not shorten.
However, she explains at length that stressors can accelerate their shortening. The point that she is hinting at is that telomere shortening might be a consequence, rather than a cause, of diseases.
To put it differently, poor lifestyle can accelerate aging, as measured by telomere length. In these cases, the telomere length is a consequence of aging, and not the cause.
But…
The video is from 2012. There is has been quite a bit of research since then. Last year, in vitro, we were able to show that resetting the telomeres in stem cells effectively rejuvenate them.
So, in vitro, for individual stem cells, telomere length is a powerful epigenetic clock.
It does seem therefore that telomere length could act both as a cause and a consequence of aging. Maybe.
Telomeres don’t necessarily shorten as you age, normally the enzyme telomerase compensates for the shortening. Only if you live unhealthy (smoking, eating bad food, …) the telomerase can’t function properly, and telomeres will shorten.
See how Elizabeth Blackburn explains it: https://www.youtube.com/watch?v=-lNR1xZS5GY (part 3 of a lecture, but she starts with a summary of part 1 and 2 where she says what I said here).
Telomeres tend to shorten as you age whether you live a good life or not. Nowhere does Blackburn claim that they do not shorten.
However, she explains at length that stressors can accelerate their shortening. The point that she is hinting at is that telomere shortening might be a consequence, rather than a cause, of diseases.
To put it differently, poor lifestyle can accelerate aging, as measured by telomere length. In these cases, the telomere length is a consequence of aging, and not the cause.
But…
The video is from 2012. There is has been quite a bit of research since then. Last year, in vitro, we were able to show that resetting the telomeres in stem cells effectively rejuvenate them.
So, in vitro, for individual stem cells, telomere length is a powerful epigenetic clock.
It does seem therefore that telomere length could act both as a cause and a consequence of aging. Maybe.