Thanks to the requests to talk about this - there's been articles popping up now and then about telomere length and so I just wanted to give a few quick points you can talk the next time you're stuck in an elevator.
Most of the cells of your body are always dividing, throughout your entire life. During this process, your chromosomes are copied so that each cell ends up with a complete set. Chromosomes are very similar to the assembly instructions you get from Ikea - overly complicated, near unintelligible, and with more information than you could ever need. But, just like assembling Ikea furniture, the cell division process can be a little messy - chromosomes can be damaged by all sorts of things (anything that causes oxidation, hence the rise of antioxidants). Damaged chromosomes make faulty parts in your body and are suspected to be the whole reason for most diseases out there, especially ones that get more prevalent as you age, and maybe even aging itself.
A way of safeguarding against that damage to the chromosomes was creating protective end-caps around the chromosomes to keep them safe and make sure the information can be properly copied. These protective parts are the telomeres.
Imagine you're shipping something very delicate back and forth across the country. You fill the box with packing peanuts the first time. And every time someone opens it and repacks it, they lose a few of those peanuts. At some point, those peanuts are all or mostly gone and whatever you were shipping is going to be damaged at some point. That's what happens to telomeres over time, leading to chromosomal damage and that leads to bad hearts, lungs, kidneys, cancer, etc. Or so the theory goes.
That said, people have been fascinated to look at telomere lengths in older people and try to figure out what can make them stay long and protective. There's a lot of evidence out there but it usually ends up corrupted into some form to make you buy something someone is selling.
I'm sorry to tell you at this point, that there is not a magic answer. The best information I have for you comes from this review article. The short answers are:
"- Telomere length shortens with age.
- Rate of telomere shortening may indicate the pace of aging.
- Lifestyle factors such as smoking, lack of physical activity, obesity, stress, exposure to pollution, etc. can potentially increase the rate of telomere shortening, cancer risk, and pace of aging.
- Dietary restriction, appropriate diet (high fiber, plenty of antioxidants, lean/low protein, adding soy protein to diet), and regular exercise can potentially reduce the rate of telomere shortening, disease risk, and pace of aging."
Conveniently, when I was listening to a Zenmaster a few months ago, he brought up the study showing that 20 people who had practiced long term Zen meditation had significantly longer telomeres than 20 people about their same age so there is probably something to the idea of mindfulness and stress management and maybe something to those tales of Zen monks who lived for thousands of years.