Hayflick Limit, Intermittent Fasting, and Life Extension
There was an interesting discussion of using Intermittent Fasting for life extension at the Performance Menu a few weeks ago. Robb Wolf, in all his genius, mentioned something I'd never heard of before known as the Hayflick Limit. This principle is a conondrum for those hoping for to extend life much beyond normal human limits.
Here's a quote from the Wikipedia article that sums it up nicely:
The limit to the number of times a cell divides has been noted in all human cell types that have been fully differentiated, as well as in other organisms. It varies from cell type to cell type, and more significantly from organism type to organism type. The human limit is around 52.
I find this kind of biochemical geekiness absolutely fascinating.
I recently talked about Intermittent Fasting and the benefits that I have derived from it. In that post, I mentioned CRON (or CRAN) and how its practitioners hope to retard the aging process and extend their lives. My reasoning for doing IF is less about quantity of life and more about quality of life. If I had a choice of leading a full and active life and dying at 75 or leading the inactive life that CRONies are forced to live due to their limited caloric intake but having an extra 10 years, I would go with dying at 75 and living life to the fullest (my opinion may change as I near that age though). I find that IF allows me to find the perfect Triple Point (another gem from Robb) of Performance, Health, and Longevity. I am able to perform optimally in the gym, my health is impeccible, and I would surmise that, barring some freak accident, my longevity will be above average. I don't expect to extend my life to some beyond-human-limits age. I feel that I am merely setting myself up to live past the average life expectancy and still be a functioning member of society rather than one of the typical worn-down 80 year olds we see.
Dr. Garrett Smith mentioned on a Crossfit Live session (episode 12) many moons ago that if you ask someone if they want to live to 95, they nearly invariably say no (it's in that mp3 somewhere). That's because what we commonly see is people that live a good life until 60 or 65, then a life of poor nutrition, stress, poor sleep, and no exercise catches up with them and they spend the next 20 years dying. But there are plenty of vibrant, energetic, and strong septuagenarians and beyond. These folks don't exhibit that typical wasting away, medicated lifestyle characteristic of aging. That is what I'm shooting for - 85+ years of life and then a quick, natural death rather than 65 years of life and a long, drawn-out death that takes 20 years and saps every bit of life from my soul; alive, but not truly alive. In the natural world, death is a quick process and as Dr. Smith notes, after an accident or injury, the healthy tend to either get better or die rather than languishing in an ever-increasing cycle of loss of independence, function, and health. "Get better or die," as cold as it sounds, is the way nature works.