Article courtesy of American Specialty Health

What’s a Telomere and What’s It Got to Do With Aging?

Telomeres are special strands of DNA (deoxyribonucleic acid) that form caps at the ends of chromosomes that live in every cell in the body. They help protect chromosomes from harm and from losing vital genetic information each time a cell divides—two problems that can kick the aging process into motion.

Why aging begins when telomeres grow too short

Telomeres slowly wear down and shorten over time. In fact, each time a cell divides, the telomeres inside that cell gets a bit shorter. At some point, this causes the cell to stop functioning and to stop dividing. And it leaves chromosomes exposed to the type of damage that’s linked with aging and disease—such as heart disease, Alzheimer’s disease, diabetes, and some kinds of cancers.

Kenneth Pelletier, Ph.D., M.D., a professor of medicine at the University of California, San Francisco (UCSF), and author of more than 300 published journal articles in epigenetics and disease management, explained how the ends of telomeres are akin to the plastic caps on a shoelace. Once the caps get too short or fall off, the shoelace tends to unravel.

“So, when the shoelace frays, you can’t get it through the hole on your shoes anymore, and you probably throw the shoelaces away,” said Dr. Pelletier.

“Same thing happens with the telomere when the ends fray. They don’t replicate accurately. So, the integrity of the tip and the length…is the measure, if you will, of integrity and long life, and both of those are governed by [a] very specific lifestyle.”

Dr. Pelletier went on to explain that, while our genes themselves can’t change, they can be damaged once telomeres grow too short.

“Once damaged, they will pass on the damaged information,” he said. “That leads to, basically…we’re not as smart, as fast, as flexible, etc., as we were at 20,” he said. “It’s really due to this loss of information or cumulative genetic damage.”

Dr. Pelletier’s insights shed light on how and why the body ages and why the job telomeres perform in protecting your chromosomes is such a vital one.

The importance of telomeres

Chromosomes house all your life-giving genetic matter, such as your long strands of DNA and, within your DNA, your genes. Each gene is a code—or set of instructions—for making protein molecules, as well as other kinds of molecules, that make up all the tissues in the body. So, if that code (a gene) gets lost or corrupted, signs of aging or disease can ensue.

And again, telomeres, when healthy and intact, do more than protect your genes. They also allow your cells to divide, which is another way your body regenerates itself as you go through life. Once telomeres grow too short, more cells stop dividing, and the body does not renew itself as well.

How to protect your telomeres for healthier aging and a longer life

Even though aging is a fact of life, you do have some influence over it. You can help slow the rate at which your telomeres shorten, and, in turn, how fast you age and how healthy you stay in the process.

Dr. Pelletier notes that one of the biggest misconceptions many people have is that our genes dictate how fast we age and which diseases we may get and when—and that there’s not much we can do about it. But Dr. Pelletier states that really only about 5 percent of our genetic makeup is set in stone.

The rest, the other 95 percent of who we become as adults, comes down to lifestyle choices, along with various environmental factors people are exposed to in life, according to Dr. Pelletier.

By lifestyle choices, Dr. Pelletier is referring to certain habits, good and bad, that may either help keep your telomeres intact for longer—or shorten them faster. Habits such as how healthy a diet you eat, how well you manage stress, how much you exercise, etc., can help slow the rate of telomere shortening.

The other piece of good news? While practicing healthy habits for your entire life may be ideal for protecting your telomeres, it’s never too late to start. Making healthy habit changes, no matter your age, can slow the rate of telomere loss and perhaps how fast you age.

“It’s never too late,” said Dr. Pelletier. “The sooner you start, the better…and the more likely it is to have an impact. But if a person is 60, 70, or even 80, and begins to change and adapt their lifestyle practices, they can have a positive influence, and it’s measurable on the telomere length.”

Can healthy habits actually lengthen telomeres?

The news gets even better. Early findings suggest that the right habits might not only slow the rate at which telomeres shorten, those same habits might also help lengthen your telomeres.

“There are many studies, actually, at this point which demonstrate that the telomeres can be elongated—and elongated in a very short time interval,” explained Dr. Pelletier.

Dr. Pelletier described one UCSF study in particular, that looked at changes in telomere length after participants switched to a 16-week, low-fat diet that was high in plant-based foods and cold-water fish.

“So, the diet was basically a somewhat modified version of the Mediterranean [diet],” said Dr. Pelletier. “And at the end of the intervention they found the telomeres had elongated and the tips had become more intact, a very positive change.”

7 key health habits to help protect your telomeres

So, what habits are key for extending the lifespan of your telomeres? Here are 7 that research has found may help:

  • Healthy eating. Studies suggest choosing a high-fiber food plan, rich in antioxidants and polyunsaturated fats, may lessen inflammation and oxidative stress and thereby slow the rate of telomere loss. On the other hand, a nutrient-poor diet high in sugar and saturated fats may speed up telomere shortening.

Some research suggests that eating the Mediterranean diet may help slow the wear and tear of telomeres. Mostly plant-based, it centers around cold-water fish, small amounts of dairy, whole fruits and vegetables, whole grains, and nuts and seeds.

  • More research is needed on just how much and what kind of exercise can help preserve telomere length. But some findings suggest that aerobic exercise may help activate telomerase, an enzyme that helps slow telomere loss.

A handful of studies suggest that routine workouts may even lengthen your telomeres. One study in particular found that adults who got 120 minutes of aerobic exercise per week for 24 weeks had longer telomeres at the end of the study than they did at the start of it.

  • Weight management. Obesity may boost inflammation and oxidative stress, which in turn may speed up telomere loss.
  • Studies have found that current smokers have shorter telomeres compared to never smokers or former smokers. If you need help quitting, talk with your doctor about quit aids.
  • Social support. Some findings suggest a lack of social support can lead to loneliness, stress, and sleep troubles. These in turn may increase inflammation and accelerate telomere wear and tear. Taking steps to build your social circle is key to healthy aging. Learn how to make new friends and nurture caring, meaningful bonds with them.

Wrapping your head around the science of telomeres

The nitty gritty details behind the science of telomeres and their role in aging can be a bit complicated.

To start, maybe focus on adopting the habits above to help protect your telomeres and support your healthy aging journey. And if you want to learn more, know that you can gain a clearer picture of how it all works.

Dr. Pelletier describes how first learning about telomeres was a challenge, and about a mentor who helped him.

“I need, obviously, to discuss telomeres and the woman who won the Nobel Prize for the discovery of [them]. Her name is Professor Elizabeth Blackburn. She’s a faculty member here at the UCSF School of Medicine,” said Dr. Pelletier.

“So I went to her and I asked, ‘Can you teach me about telomeres?’” continued Dr. Pelletier. “In retrospect, it was really insulting. It’s kind of like asking Einstein to help you with basic math!”

Check out the TED Talk by Dr. Elizabeth Blackburn for an insightful and fascinating explanation of telomeres and aging.

Take the driver’s seat on your healthy aging journey

Aging is a normal part of life. But can you see how you might have more control over it than you thought? Forming healthy habits to protect your telomeres is a choice. And it isn’t so much about living to 120. What matters more is making however many years you have left as healthy, vital, and disease-free as possible.


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