The term “telomeres” has been appearing in the news frequently in recent years and one reason is the critical role they play in human health. In particular, telomeres seem to be a key to several life secrets regarding aging, cancer, and other medical mysteries. But what are telomeres, exactly? Let’s open a few doors and see what the experts have uncovered about telomeres thus far.
What Are Telomeres?
At the end of your chromosomes (the twisted strands of DNA in your cells) are sections called telomeres, which consist of DNA sequences and protein. These telomeres perform several tasks that are important for your health, such as:
- Protecting the genetic information stored in your genes
- Playing a critical role in helping your cells divide
- Holding secrets about your health, such as how you age and how you may develop cancer. If you didn’t have telomeres, the ends of your chromosomes could be damaged and cause your cells to die or eventually result in disease such as cancer.
Here’s another critical characteristic about telomeres. Cell division is a part of life and is necessary for making new bone, blood, skin, and other cells. Each time your cells divide, your telomeres get shorter. When your cells reach a point where they can’t divide any more, they either stop all activity or they die.
In either case, the process of telomere shortening is associated with cancer, aging, cardiovascular disease, obesity, osteoporosis, and death. The good news is that your telomeres do not get shorter in cells that do not continually divide, such as your heart muscle. However, many other telomeres continue to disappear.
Telomeres and Environment
A recent study looked at the relationship between a child’s social environment, telomere length, and health, and the results were surprising. The authors discovered that African American males (5,000 boys age 9 in this study) who grew up in highly disadvantaged environments (i.e. low income, poor maternal education, harsh parenting, unstable family structure) had shorter telomeres (19 percent shorter) than did their peers who grew up in highly advantaged surroundings. This seems like a strange finding until you hear the rest of the story.
The authors also found a genetic factor was involved; that is, boys who had the highest genetic sensitivity regarding stress factors (e.g., serotonin and dopamine) had the shortest telomeres when they were exposed to highly disadvantaged surroundings and the longest telomeres when their environment was highly advantaged.
This suggests that African American boys who live in a chronically stressful environment experience a type of physiological aging early in life. It also implies, according to the authors, “the importance of early intervention to moderate disparities in social and educational opportunities.”
Telomeres and Aging
One example of the relationship between the length of your telomeres and aging (lifespan) was seen in a study by geneticist Richard Cawthon and his peers at the University of Utah. They separated a group of people by the length of their telomeres and found that those with longer telomeres lived an average of five years longer than did those with the shorter telomeres.
The team also found that among adults older than 60, those who had the shortest telomeres were eight times more likely to die from an infectious disease and three times more likely to die from heart disease.
But don’t despair, because scientists also have seen that people have telomeres that are much shorter than some mammals who have much shorter life spans. That means the length of your telomeres is not the only factor that has an impact on the length of your lifespan. (But you probably already guessed that.)
Read more about how to age gracefully
Cawthon’s team also suggested that people with short telomeres might lengthen their lifespan by five years if they could increase the length of their chromosome protectors. This suggests you can do something to influence the length of your telomeres. It just so happens a research team has explored this idea.
How to Improve Telomere Length
You can improve the length of your telomeres, according to the results of a small pilot study published in The Lancet Oncology, if you make some lifestyle changes. The study, which was headed by Dean Ornish, MD, founder of the Preventive Medicine Research Institute and a clinical professor of medicine at the University of California San Francisco (UCSF), compared two groups of men, all of whom had prostate cancer. Over five years, one group made no lifestyle changes while the other group followed a plant-based diet, walked for 30 minutes a day six days a week, practiced stress reduction (e.g. yoga, meditation), and attended a weekly support group.
Telomere length increased about 10 percent among the men who adopted lifestyle changes, but it declined about 3 percent in the other group. Co-senior author Peter R. Carroll, MD, MPH, professor and chair of the UCSF department of urology noted that “We believe that increases in telomere length may help to prevent these conditions [chronic diseases] and perhaps even lengthen lifespan,” and that their findings apply to the general population and not just men who have prostate cancer.
Now you know that the dangling ends of your chromosomes hold a key to your health and your lifespan. Although telomere research is still in its infancy, it’s a safe bet that adopting positive lifestyle habits is the right direction to take while waiting for the rest of the mystery to unfold.
Image: Steve Jurvetson