This year, on my 27th birthday, I got test results back from a company called Life Length. A few weeks earlier, I sent them a tube of my blood on dry ice, and they measured my telomeres—the last few thousand base pairs of my chromosomes.
Telomeres prevent you from losing important bits of DNA during cell replication—they are often compared to the plastic tips on shoelaces that keep them from fraying. Each time a cell divides, the replication process can’t copy all of our DNA, and a little gets missed from the ends. The telomeres are there to make sure nothing of value is lost.
My telomere length results were supposedly going to tell me my true biological age, not my chronological age that I had counted with days and months for 27 years. Everyone’s telomeres gradually get shorter as all the cells in our body divide over and over again. With each replication, a little more is sliced off the ends of the telomeres, and when they get too short, a cell stops replicating—a state called cell senescence.
An individual’s telomere length has been shown to correlate with overall health, and also has associations with a myriad of diseases, including heart disease, diabetes, cancer, osteoporosis, Alzheimer’s, and many more. There are hundreds of scientific papers that show a correlation between short telomeres and something bad—including overall mortality. Basically, if your telomeres are short, you might be more likely to die sooner.
With this seeming connection to longevity, I’d noticed a bunch of tests popping up—23-and-Me style— that measured your telomeres and told you your “real” age according to your telomere length. To see what they were all about, I took Life Length, and another called Teloyears, and compared the two. Both tests were provided to me for free.
I wasn’t worried about my telomere length before taking the tests—I was actually over-confident. I eat right and exercise, and don’t have much family history of disease. I do have OCD and anxiety (and okay, probably should sleep more) but I felt pretty sure that my lifestyle would result in long, beautiful telomeres.
Then, I opened the email from Life Length. It said my biological age was 34, and that I was in the bottom 5-10 percentile—so only nine percent of 27-year-olds had a median telomere length shorter than me. My Teloyears results said that my biological age was 30, a little better, but not by much. Happy Birthday to me. I had promised myself not to take these results too seriously before I did more research, but it freaked me out. I won’t say it ruined my birthday, but it definitely put a damper on it. Did this mean I’d start getting health problems that people get at 45, at 35? Or more importantly, was I going to die earlier?
Until the 1960s, scientists thought that cells were immortal. In 1961, scientists found that cultures from the lung would only divide 40 or 50 times, so our cells couldn’t continue replicating forever, after all. In 1998, it was shown that cells with re-lengthened telomeres could be “re-set” and skip senescence, and in 2009, Elizabeth Blackburn, Carol Greider, and Jack Szostak won a Nobel Prize for their discovery of telomerase— the enzyme that elongates telomeres—that is shut off in most adult cells after early development.
Telomeres have since had the reputation as a key to anti-aging, says Jerry Shay, a biologist and professor at the University of Texas Southwestern Medical Center who has been working on telomeres for decades. “Once telomeres became popular knowledge, all sorts of people came out of the woodworks selling nutraceuticals, natural products, claiming that it was the fountain of youth,” Shay says.
Maybe telomeres are still a little esoteric, but I’ve seen mainstream articles touting their anti-aging properties, like one in Prevention called, “Meet your Anti-Aging Future,” or a recent interview in Goop called, “Slowing Down Aging.” The problem with these types of articles, is that while telomere length has definitely been linked to cellular aging, not everyone is convinced it’s connected to aging overall.
Some of the evidence seems to indicate so. Those with shorter telomeres have been shown to have poorer survival, and a higher mortality rate from heart disease and infectious disease. Women with high levels of stress had telomeres the length of women a decade older than them. A BMJ meta-analysis from 2014 looked back at 24 studies involving 43,725 participants and found that those with shorter telomeres had a higher risk for coronary heart disease, independent of other risk factors.
In 2010, a Nature study showed that when mice were engineered to lack telomerase, and then given it back, a whole host of health and aging problems reversed. “Shrivelled testes grew back to normal and the animals regained their fertility,” a news article in Nature wrote. “Other organs, such as the spleen, liver and intestines, recuperated from their degenerated state.” The mice’s brains also changed: those with restored telomerase had larger brains and were more capable of producing new neurons.
But some researchers aren’t sold—it’s accepted that telomere length could be a biomarker for aging, but not that it somehow causes aging. The difference is slight, but important. There are those that think that your telomere length is responsible for these diseases, and some that think it’s just a side effect. “We haven’t established a causal link between telomere length and health,” Dana Glei, a senior research investigator at Georgetown University, told The Scientist in 2016 . “If it’s like gray hair, dyeing your hair won’t make you live longer.”
The interesting thing about telomere length, and I think the reason it’s caught on in the wellness world, is that numerous studies show basic lifestyle and mental health interventions can affect and change them. A person who does any exercise at all is 3 percent less likely to have very short telomeres, and the more you exercise, the longer your telomeres seemed to be. Plant-based diets seem to boost telomerase activity, and lengthen telomeres. Multivitamin use was associated with longer telomeres in women. Those with higher levels of psychological stress have lower telomerase activity and shorter telomeres.
A study from the Lancet in 2013 found that in a group of men with low-risk prostate cancer, lifestyle changes like diet and exercise over the course of five years could increase telomere length, compared to the ones who didn’t do anything. Another study showed that in women with breast cancer, those who did yoga and practiced mindful meditation were able to maintain telomere length, while those who didn’t had shorter telomeres. Still the question of causality remains: Are you healthier because your telomeres are longer? Or are your telomeres longer because you are healthy?
For those who believe the former, enter: the supplements. HealthyCell, TeloVite, IsaGenesis, Telomere Advantage, Telomeron, TA-65—these are just a few of the supplements I saw whose primary goal was to lengthen telomeres in order to make you healthier. TA-65 is probably the most well known telomere supplement, because they have done a double-blind placebo trial that showed in 117 people that those who took their supplement had longer telomeres after a year. Its active ingredient is extracted from astragalus, a common herb in traditional Chinese medicine.
I try to be very skeptical of supplements without rigorous data behind them, but honestly—after I got my results saying my body was 7 years older than I “really” was—I was tempted to buy some. At $100 per month, TA-65 is not an affordable habit. But what if it worked? Didn’t I need to rescue my telomeres?
My reaction to my telomere length, according to Mary Armanios, is the exact reason these kinds of tests shouldn’t be available. Especially, she says, when the science isn’t quite figured out yet.
Armanios is the clinical director of the Telomere Center at Johns Hopkins University, and works with Carol Greider, one of the Nobel recipients for the telomerase discovery. Armanios studies and treats telomere spectrum disorders or telomere syndromes; diseases like dyskeratosis congenita and idiopathic pulmonary fibrosis. We know, she says, that these are directly caused by very short telomeres— way shorter than my own. She says that these patients have highly specific problems related to short telomeres—but overall they don’t have all the diseases of aging. “I think that begs the question as to whether short telomeres cause all of aging,” she says.
“I find it very difficult to understand why companies would alarm the public and say your telomeres are shorter and therefore you’re ten years older than your age,” she says. “It doesn’t make sense for many reasons, but it may be misleading because the normal range for telomere length is wide. And likewise, it may tell someone who is 50 that their biological age is actually 40, and that person would feel like they don’t need to have a healthy lifestyle. That would be falsely reassuring that person.”
She thinks that we don’t know enough about how much shortening is biologically relevant to make these kinds of statements—is five base pairs important? 50? 100? The desire that these tests promote is for the longest telomeres possible. I wanted my telomeres to be in the ‘green’ zone, not lingering dangerously close to the red. But longer telomeres, we’re now discovering, might not be a great thing because they may be associated with cancer risk.
Our telomerase levels are highly regulated, Armanios says, so it seems the body wants to preserve telomere shortening with age, not lengthening. Extremely long as well as short telomeres are now being associated with specific cancers, and Shay says that most cancers activate telomerase (cancer’s tell-tale characteristic is endless replication). His lab has done a lot of work trying to figure out how to turn telomerase off, rather than turn it on, as a cancer therapeutic approach.
Armanios says that telomere tests, like the wide range of genetic tests proliferating the market, represent a greater trend in our society. “We have become so biologically focused, thinking that biology is going to tell us something about ourselves,” she says. “It’s part of a medicalizing of wellness. I study the telomere, I’m a telomere doctor, basically, and there is value to this science to understanding and treating human disease for human health. But not in this way, nowhere close to what this is being claimed as.”
Another problem, says Michael Fossel, the author of The Telomerase Revolution, is that most studies (and the tests I took) usually measure the telomeres in your white blood cells, or leukocytes—which might give a good indication of your immune system health, stress or environmental factors. But most of us, statistically, will die of heart disease or failure, so the telomere measurement that would matter more– at least to understand disease risk and longevity—would be from your vascular endothelium. That’s not a procedure you want to suffer through, he says. There are other ways to evaluate these risks—one study showed that there are more than a dozen other tests that are better at predicting five-year mortality than telomere length.
By measuring telomere length in white blood cells, "what you're really reporting on is the capacity of immune stem cells to function well," Matt Kaeberlein, who studies the molecular basis of aging at the University of Washington, told STAT earlier this year. "What this may be really telling us is the immune system may be particularly sensitive to lifestyle and environmental factors.”
And what about the supplements? Armanios, again, says that she doesn’t find the evidence convincing. “If these compounds were lengthening telomeres, there is nobody who would be more eager to study them in the mainstream of science and medicine, than someone like me.”
“Biology is complicated, aging is very complicated, and telomeres have been the most advertised mechanism of cellular aging,” she says. “But probably they are not relevant to everybody, and I hope we can invest and understand more about what is causing aging. It’s a fascinating biological question and it’s still in its infancy. How do cancers overcome the aging problem is a major question. So there’s lots of exciting work to be done, and there’s certainly relevance. But I think the relevance will be more powerful and will have a bigger impact on human health if we can actually agree on where it is relevant and not just apply it to everybody without evidence.”
Stephen Matlin, the chairman and CEO of Life Length, disagrees with Armanios's criticisms, and says that Life Length, in particular, overcomes many of the other tests' shortcomings. Their test, he says, measures individual telomeres and gives the median, rather than the average, telomere length. By doing so, he says their "biological age" is not based on the falsely coveted longer telomeres but by the 50th percentile of the distribution.
Further, he wrote in an email: "We agree that telomeres are not the only factor involved in and responsible for aging and causing age-related diseases...And as a result, we don’t estimate biological age on the telomere length alone but rather use it as part of an algorithm in which the median telomere length accounts for about a third of the calculation of biological age, and the other two thirds are based on the patient’s chronological age which takes into consideration other factors like oxidative stress, mitochondrial function etcetera."
He hopes that taking a test like Life Length won't freak people out, but push them to care of their health before chronic diseases– that may have short telomere length as a biomarker– take hold. Knowing your telomere length could nudge you to be more motivated about everyday health choices, he says.
Life Length does have broader scientific goals as well. With all their test results, they’re accumulating a large dataset, and hope to use it. Combined with lifestyle information they collect, they want add to longitudinal work to understand what illnesses telomere length is really associated with. Additionally, in 2016, they received a prestigious European Union award, the Horizon 2020 grant, which gave them 3.1 million euros to collaborate with Spanish hospitals to try to validate the clinical utility of their telomere-measuring assay in diagnosis and prognosis of cancer. One goal, Matlin says, is seeing whether measuring telomere length in cancer patients can determine which treatments will work best for them. They plan to do something similar with infertility and cardiology.
Controversy aside, something I liked about the Life Length test is that they don't sell directly to consumers, but works through people’s doctors. I got my kit sent to me directly to write this story, but if I hadn’t, I would have needed to coordinate with my primary care physician.
“Because this is a new area of emerging science, in terms of clinical practice, you cannot say with telomere tests alone: You are going to have a heart attack, you’re going to have diabetes,” he says. “You have to look at the overall picture of the patient. We don’t think we should sell directly to the consumer at the current time. We think that when you put this in the context of the doctor, of a check up, who is looking at the other metabolic factors, other tests, the clinical history—it’s much more robust and much more useful.” He thinks that telomere testing could one day be like cholesterol testing— a routine sample your doctor takes that plays a role in assessing your overall health. He also says cholesterol testing too was first met with skepticism.
Matlin says that while some studies show that certain vitamins and supplements can affect telomere maintenance and function, they don’t generally recommend any supplements to their clients, since they don’t communicate with them directly. They do have a doctor on-call to go over your results with you, if you need one, who I spoke with. This doctor did recommend supplements to me, that he strongly suggested would lengthen my telomeres: like milk thistle and fish oil. The ingredients for all the "telomere supplements" I saw are mostly herbal, things like B vitamins, green tea powders, milk thistle, omega 3-s. I even read a recent interview in Healthy-ish with Eliza Coup, where she said she eats blueberries because they lengthen your telomeres.
Blueberries are really good for you, and so is having adequate levels of B vitamin and the right ratio of omegas. But if they specifically activate telomerase activity to lengthen telomeres—the jury is out. It’s probably better to maintain overall health, and eat foods that are healthy, than obsess over foods specifically to boost telomerase.
When I go over my results with Shay, he is quick to try and make me feel better. “It tells you nothing, it’s just ‘my telomeres are longer than your telomeres’ stuff.” He assures me.
Whenever I told any researcher my subpar telomere lengths, our conversations quickly became highly personal. They told me not to worry, but to try to get more sleep, or do yoga. Shay, when looking at my Life Length report, did call my lymphocytes beautiful, and recommended I listen to classical music when I get home from work and “turn off the TV.”
Matlin probably has to communicate nice stuff about his own company, but Shay backed up much of what he had to say. He confirmed that Life Length, though the most expensive, is also the most sensitive commercial test on the market because it measures individual chromosomes. He said it’s true that it’s hard for scientists to collect large datasets, and he was encouraged by companies that weren’t only trying to make money— but putting something back into the science community. He even thinks further study of supplement TA-65 is worthwhile, because if it works, it could really help people with super short telomeres.
“The only way we’re ever going to know if telomere length is a biomarker of healthy aging is by doing longitudinal studies,” he says. “And the only way that’s going to be done, because the federal government certainly isn’t going to pay for it, is if there’s a commercial interest in that.”
Shay also confirms that my results are probably less indicative of when I’ll die, or if I’ll get heart failure, and more a reflection of my health and stress levels the week I sent in my blood. He calls it “a tap on the shoulder,” a little nudge from my peripheral white blood cells that I could be taking better care of myself in some way. (He also said reporters he’s talked to usually have short telomeres because we’re “freaked out by deadlines.”)
At the end of the day, understanding telomeres and telomerase will give us a lot of insight into cancer growth and treatment, short telomere diseases, and potentially, even aging. But the focus on immortality and anti-aging probably distracts from some of the more important, accessible stuff. “I believe aging is fairly complex, I also think it’s multifactorial, and I suggest that instead of trying to find some universal truth to aging, that what we should be doing is trying to understand all of these different components,” he says. There isn’t one solution to extending healthspan, just like there will never be one pill to fix your health.
So should you get your telomeres measured? If you’ve got anywhere from $89 to $400 that you won’t miss, and a calmer demeanor than me, it’s a neat thing to know, and you could be contributing to a dataset that might be useful down the road. Will I do it again to see if my telomeres have gotten longer or shorter? I’m a nerd who loves to use her own body for scientific experimentation, so maybe. I’m curious to know if doing yoga or going on vacation will change my results. The bottom line is, it’s a cool insight into aging biology, but nothing to shorten your telomeres worrying about.