Youth and aging could be traced to telomeres, which are bits of DNA that cap the ends of a chromosome to protect it from damage.

The University of California San Francisco (UCSF) likened telomeres to the plastic caps at the end of a shoelace.

“As the plastic ends shreds and the shoelace becomes frayed and damaged, so too the shortening of our telomeres can leave our cells vulnerable to damage,” UCSF said on its website.

According to UCSF, studies have shown associations between shorter telomere length and various types of diseases such as stroke, heart attack, diabetes, cancer, osteoporosis, cognitive function, dementia and arthritis. By contrast, long telomeres are related to healthy aging and overall longevity.

In 2009, Australian-born Elizabeth Blackburn, British-born Jack Szostak and Carol Greider won the Nobel Prize for Medicine for their work on telomeres and telomerase, an enzyme that helps prevent the fraying of chromosome that underlies aging and cancer.

Dr. Tim Spector of St. Thomas’ Hospital in London, in a study published in 2005, found that people who smoked cigarettes or were obese had shorter telomeres, making them biologically older than their nonsmoking, leaner counterparts.

Spector said that obesity and cigarettes increased oxidative stress or the damage to cells and DNA caused by charged particles found in the environment and caused by everyday biological processes.

The cumulative damage over time causes the loss of telomeres which is believed to be a marker of accelerative aging.

Based on studies, UCSF cited some factors that may help maintain and lengthen telomeres and these included increasing vigorous exercise to four to five times a week, improving overall nutrition, losing extra weight if overweight and enhancing well being by reducing psychological stress and depression level. Ana Roa, Inquirer Research

Sources: University of California San Francisco, Inquirer Archives