By Dr. James Aw, National Post/QCostarica
I recently came across two candidates for the fountain of youth. The first came in the form of a longtime patient of mine, an early adopter who makes it a practice to stay on the forefront of medicine so he gains an edge. At 60 years old, the successful entrepreneur confessed he was taking something to stave off the effects of aging — an enzyme called telomerase.
The second involves an article I read recently in The New York Times Magazine, about a Greek island where people just forget to die — Ikaria, the place is called. Men there reach the age of 90 at four times the rate of American men. Ikarians in general, the magazine reported, lived eight to 10 years longer and suffered a quarter the rate of dementia. The cause? No single magic bullet. Instead, it’s lifestyle stuff. They get plenty of sleep. They stay active, avoid saturated fats and maintain active social lives.
So which is better? Lifestyle or chemical supplement? First, let’s examine the chemical option. Telomerase is an enzyme that protects the tip of the chromosome, which is called the telomere. The telomere gets shorter each time the cell divides.
Eventually, the telomere becomes so short the cell can’t divide, and the cell dies. Writ large, the process may play some sort of a causal factor in our bodies’ aging — we may age because the telomere shortens.
So could the reverse also be true? Could we stave off aging by preventing the telomere from shortening? And if telomerase prevents the telomere from shortening, could we stave off aging by ingesting the protective enzyme, telomerase?
Data remains inconclusive about the enzyme’s effect on humans. But the telomerase hype increased last year after the journal Nature published a fascinating study about the enzyme’s effect on genetically engineered mice.
In the study, researchers bred mice that, in normal conditions, didn’t create telomerase. The mice grew to adulthood without the enzyme. Then, for a month, the team provided the mice with a trigger chemical that allowed the mice to create telomerase.
Without the telomerase, the researchers discovered that the mice tend to age prematurely. They contracted osteoporosis or diabetes, and they tended to die earlier than normal mice. Then, during their month with telomerase, things turned around.
Sterile animals became fertile again. Prematurely aged internal organs returned to health. Telomerase also reversed aging’s effects in the mouse’s brains.
So would this stuff work in humans? Telomerase hasn’t been conclusively proven to help humans. But anyone who Googles “telomerase supplements” is apt to find dozens of reports that it does. The problem? It’s risky. Taking telomerase may pose serious risks to people who have cancerous tumour cells. The enzyme appears to encourage tumour growth. The danger here is that a person who has cancer, but doesn’t know it, may take telomerase and cause the cancer to grow and spread.
Besides, the evidence suggests that modifying the way you live is more effective at prolonging life than taking an unproven supplement. The British Medical Journal published a study earlier this fall that followed about 1,800 people over the age of 75 from the Swedish town of Kungsholmen. Maintaining active social networks, pursuing leisure activities, avoiding smoking — these things tended to prolong life. “The estimated effects were large,” a BMJ editorial noted. “Participation in leisure activities categorized as ‘productive,’ ‘social’ or ‘physical’ predicted 0.9-1.4 additional years of survival.” What struck me was the way the BMJ study’s findings replicated what researchers found on the Greek island of Ikaria — and in other areas of the globe where higher-than-normal percentages of people live past 90, such as Okinawa, Japan and Nicoya in Costa Rica.
Those same lifestyle factors may be increasing the body’s telomerase levels anyway. That was the gist of a 2008 study conducted by Dr. Dean Ornish and published in 2008 in Lancet Oncology. It was a small pilot study of just 30 men that established that some key lifestyle factors — such as decreasing stress and low-density lipoprotein cholesterol levels — could increase telomerase levels.
Lifestyle or chemical? Maybe at some point we’ll determine telomerase is a fountain of youth — but to my mind, we’re much better off pursuing things we’re certain that work, just like the Ikarians.
Dr. James Aw is the medical director of the Medcan Clinic, a leading private health clinic in Toronto.