Last month two new studies from prominent journals put a new spin on the old, "Get off the couch and start walking (or running or cycling or swimming). I was thrilled to hear that over in the UK, a well constructed study in Plos Medicine following over 20,000 healthy men and women, aged 45-79 years old, for an average of 11 years, demonstrated how we can gain extra years by exercising, drinking just a little, eating at least 5 fruits & veggies, and not smoking.
Each person in the study was given a point for each of 4 healthy behaviors: not smoking, exercising, moderate alcohol intake, and eating at least 5 servings of fruits and vegetables a day. The fruit & veggie intake was actually verified by measuring the participants' plasma levels of vitamin C. At end the of the eleven years the authors looked at who had died, and compared the folks who were practicing all 4 healthy behaviors with those who weren't doing any of them. The folks with a score of 0 were 4 times more likely to die (especially from cardiovascular disease) than the folks with a score of 4. The authors concluded that a person practicing NONE of the 4 healthy behaviors (with a score of 0) has the same risk of dying as a person practicing all 4 healthy behaviors who is 14 years older. Take home message: EXERCISE- EAT AT LEAST 5 FRUITS & VEGGIES A DAY-HAVE A TINY NIGHTCAP-FORGET ABOUT SMOKING. Not much effort for an extra 14 years!
Here's another prod to get you to JUST DO IT! In the January 28, 2008 issue of Archives of Internal Medicine researchers compared the length of leukocyte telomeres (a marker of aging) between twins who exercised and those who didn't. They chose twins for this study because they share much of the same DNA & are raised in similar environments as children. This way they're really comparing apples to apples. They found that those who exercised, based on their telomere length, were biologically younger than those who didn't. Again, exercise can make you younger. In fact, those who exercised the most, putting in more than 3 hours of vigorous activity had the longest telomeres, which compared to the length of the couch potatoes who were 10 years younger!
Which brings me to the telomere story. Telomeres are like the plastic tips on our shoelaces that protect the laces from fraying. They sit on the ends of our chromosomes, protecting our genetic data, and making it possible for the cells to divide. But the thing is, every time our cells divide (which keeps us young) the telomeres keep getting shorter, until our cells die or are damaged. Emmuanel Skorkalakes, of the Wistar Institue in Philadelphia, explains,
"When the telomeres become short, then you start cutting into actual chromosomes where there are genes essential for our body. To prevent the fraying DNA in all those aging cells from seeding maliganant tumors, the body turns them dormant. Your body shuts down more and more cells every day and you become old."
Oh joy, what we have to look forward to! As the graph shows, the younger you are, the longer your telomeres. And by the time you're 65, well, there's just not that much left. Which is exactly why not too many of us make it past 80, 90 or 100. Not to get you even more depressed about your rapidly shrinking telomeres, but there have been a number of studies that have shown how stress, especially in caregiver's of chronically ill children and spouses of Alzheimer's patients have accelerated telomere shrinking. One study even suggested that you can accelerate your biological age by as much as 17 years if you're exposed to what you perceive as high psychological stress!
So, how exactly does exercise lengthen our telomeres, and in effect, slow down our aging? That's for another research study. But until we know more, it looks as if it's a safe bet to start lengthening your telomeres now, by EXERCISING!