🧬 Telomeres and Time: Can We Really Rewind Aging?

The Lowest Hemoglobin I’ve Ever Seen

The lowest hemoglobin I’ve ever seen belonged to a young woman who was still standing. Her blood count was one-fourth of normal. She was pale, short of breath, and strong enough to walk into the clinic.

Doctors soon learned her bone marrow had stopped making new blood cells. The diagnosis was aplastic anemia — a true telomere disease.

She survived thanks to her fitness, modern science, and a bone marrow transplant from a generous donor in Germany. Two years later, she’s in law school, healthy, and full of life.

What Are Telomeres?

Each cell in your body carries chromosomes — long strands of DNA. At the ends of those chromosomes sit telomeres, tiny caps that keep the DNA from unraveling, like plastic tips on shoelaces.

Every time a cell divides, its telomeres shorten a little. When they get too short, the cell can no longer divide. Scientists call that stage cellular senescence — cellular retirement.

In 2009, researchers Elizabeth Blackburn and Carol Greider won the Nobel Prize for discovering telomerase, an enzyme that can rebuild telomeres. Their discovery sparked dreams of reversing aging. But there’s a catch: cancer cells also use telomerase to live forever. Turning that enzyme on everywhere might turn back time — or turn on tumors.

Why Everyone Talks About Telomeres

Telomeres became the poster child for longevity marketing.

Social media ads promise to “measure your biological age.” Supplement companies claim to “lengthen your telomeres” for hundreds of dollars a bottle.

The problem? Telomere tests vary between labs. Results can change by 20 percent depending on the method. They show trends, not destiny.

What’s Being Studied

Real scientists are studying how telomeres behave under different conditions.

• Danazol — a synthetic sex hormone that slows telomere loss in people with inherited marrow failure. It works but brings side effects, so it’s not an anti-aging trick.
• Henagliflozin — a diabetes drug that increased telomere length in one small study. Whether that helps humans live longer is still unknown.
• Aripiprazole — an antipsychotic that repaired telomeres in cells after oxidative stress. That’s a Petri dish result, not a prescription for youth.

These drugs show that we can nudge biology, but they’re for disease, not for vanity.

Vitamins and Compounds That Might Help

Nutrients influence telomere health, too.

• Vitamin D supports telomerase. Long-term studies show it slows telomere shortening.
• Vitamins C and E help reduce chemical stress that wears telomeres down.
• Gamma-tocotrienol, a form of vitamin E, may reverse telomere loss — so far only in lab work.
• TA-65, from the Astragalus plant, may activate telomerase but carries risk. Turning on telomerase could also fuel cancer.
• Telomir 1 is experimental and not available outside research.

None of these is proven to extend life. They’re promising ingredients, not miracles in a capsule.

What Lifestyle Still Beats Everything

Lifestyle matters more than any supplement.

A large study at UCSF showed that people who ate a Mediterranean diet, exercised, and managed stress boosted telomerase activity within months.

No powder required.

Telomeres respond to care. They’re markers of how you live, not the cause of how long you live.

Longer telomeres don’t guarantee longer life — they reflect how your body has handled time, inflammation, and stress.

What Scientists Agree On

Research tells a simple story:

• Telomeres shorten as cells divide.
• Stress, smoking, and inflammation speed that process.
• Healthy diets and regular movement slow it.
• Some medications affect telomere biology but aren’t for general use.
• We still don’t know if lengthening telomeres increases lifespan.

So far, no pill or powder beats sleep, exercise, and plants on a plate.

The Real Takeaway

Telomeres aren’t countdown clocks. They’re mileage markers.

Protect them by doing the basics well: eat plants and fish, move daily, sleep enough, manage stress, and don’t smoke.

Simple. Sustainable. Supported by science.

References

1. Calado RT, Young NS. Telomere Diseases. N Engl J Med. 2009;361(24):2353-65. PMCID: PMC3401586
2. Lai T-P, Wright WE, Shay JW. Techniques for Assessing Telomere Length. Nat Rev Genet. 2018;19(5):293-307. PMCID: PMC6380489
3. Huang S et al. The Relationship Between Telomere Length and Aging-Related Diseases. Front Aging. 2025;6:1532. PMCID: PMC11882723
4. Arsenis CA et al. Physical Activity and Telomere Length. Sports Med. 2017;47(3):503-512.
5. Schellnegger T et al. Unlocking Longevity: The Role of Telomeres and Their Targeting. Front Aging Neurosci. 2024;16:1050353.

>> Dr. Terry Simpson: The lowest hemoglobin I have ever seen in my life.

That's the blood count. And this person was

anemic. In over 30 years of surgery, I've never

seen a hemoglobin that low in someone who is still

standing. Let me tell you about her. She is the,

uh, young, 20 some year old daughter of a friend

of mine and part of one of the more active

families that I know. They don't vacation to

relax. They vacation to move, hiking, climbing,

anything outdoors. And on one of those vacations,

she started to feel a bit winded. When she finally

went to the doctor, her blood count was a

hemoglobin of 3. Yours is probably 15. She had,

after many tests, a disease called aplastic

anemia. Her bone marrow wasn't making any new

blood cells. Being young and being fit probably

saved her life. But if we looked at her DNA back

then, we would have seen something else. Her

telomeres, those little caps at the end of her

chromosomes, were almost gone. Two years later,

she's had a bone transplant. She's thriving. She's

in law school. And thanks to a young man in

Germany who was her marrow match in modern

medicine that rebuilt her blood. That's what a

true telomere disease looks like when those

genetic timekeepers run out too soon.

But what about the rest of us? What do telomeres

have to do with aging? Longevity. And all those

supplements that promise to rewind the clock. I am

your Chief Medical Explanationist, Dr. Terri

Simpson, and this is Fork you, fork University,

where we make sense of the madness of longevity

and telomeres. Bust some myths and teach you a

little bit about food and medicine. I want you to

imagine a, uh, shoelace and that little plastic

tip that keeps the shoelace from fraying.

Telomeres. Do that for your chromosomes,

protecting them, um, each time your cell divides.

But each division shortens the tip a bit.

Eventually, they get so short that the cell can't

divide anymore. That is cellular senescence or

cellular retirement. We heard about that talking

about how Leonard Hayflick discovered that

telomeres shorten naturally as we age. But how

fast they shrink depends on genetics,

inflammation, sleep, stress, lifestyle, and other

things we don't even understand yet. Elizabeth

Blackburn and Carol Glider won the Nobel Prize for

discovering telomerase, an enzyme that can rebuild

telomeres. Cue the headlines. Science find the key

to immortality. Well, not quite. Cancer cells love

telomerase. That's how they become immortal.

Cranking it up everywhere can turn back time and

turn on tumors. Telomeres are the popular poster

child. For longevity marketing, you can buy some

telomere length tests for a few hundred dollars

and a telomere supplements for a few hundred more.

The problem? Those tests vary widely between labs

and tell you trends, not your fate. And the

supplements? Well, let's take a closer look at

that. Let's start with Danazole, which is a

synthetic sex hormone used in inherited telomere

disease. Like aplastic anemia, it slows telomere

loss and sometimes lengthens them. But with liver

and lipid side effects, it's really not an anti

aging hack. There's another drug, a diabetes drug

that in one small trial increased telomere length

in white blood cells. Promising, but we don't know

that it translates at all to living longer. And

there's another antipsychotic drug that in lab

studies helped recover telomere length after

oxidative stress. Interesting in theory and

irrelevant for your supplement drug. These drugs

show that we can nudge telomere biology. But their

tools for disease, not designer longevity.

But let's talk about some other things. Vitamin D.

Vitamin D encourages telomerase activity. Long

term studies show that it can reduce telomere

shortening, keep it in the healthy range. Sunlight

and modest supplementation do the job. What about

vitamins C and E? They are antioxidants that lower

oxidative stress indirectly preserving telomeres.

But they come better from fruits and vegetables

and olive oil than from capsules. And there's

another form of vitamin E that may reverse

telomere loss in early cell. Interesting, not

proven. And then there's the all famous TA65 from

an Astragalus plant marketed as a telomerase

activator. Some small studies show modest

lengthening but no evidence of longer life.

Turning on telomerase everywhere might also turn

on cancer cells. And there's telomere one, which

is still an experiment in tissue culture. Far from

human use. Really interesting in a petri dish, but

what actually moves the needle. Large population

studies show that people who eat well, move often,

sleep enough and manage stress, have slower

telomere shortening, no pills required. University

of California San Francisco study found that

Mediterranean style diet plus exercise and

strength management increased telomerase activity

within months. No patent, no promo code, just

habits. Telomeres respond to lifestyle. They're

responders, but they are not drivers. Longer

telomeres don't guarantee longer life, they just

reflect how well your cells have been treated. In

a review of the New England Journal of Medicine

describes that families with true telomere

disease, like aplastic anemia that my friend's

daughter had or other forms of disease like

pulmonary fibrosis or dyskeratosis congenita.

Mutations in telomerase genes can cause these

conditions. Other recent studies, including

reviews in the Frontiers of Aging, show that

shorter telomeres correlate with higher risk of

heart disease and dementia. But correlation isn't

causation. Telomeres are, uh, the smoke, but not

always the fire. Research at the NIH and elsewhere

warned that measuring telomere length is tricky.

Different labs, different results. These biologic

age tests online, well, think of them as selfies

taken with a shaky camera from the iPhone. One and

another nuance. It's not the average telomere

length that triggers aging. It's the shortest

ones. Stress, inflammation and lifestyle can push

certain cells over the edge faster. A recent meta

analysis this year confirmed that people who sleep

well, exercise, avoid chronic stress, tend to have

slightly long telomeres, but the effect is small.

You can protect them. You can't game them. You

can't hijack them to make them longer or better.

What we know is that telomeres shorten with each

cell division, that lifestyle and lower

inflammation slow the process, and that certain

drugs can influence telomerase under medical

supervision. What we don't know is if manipulating

telomeres increases health span or lifespan in

human which interventions are safe long term, how

telomere biology interacts with cancer risk and

things to ignore. Ignore any telomere tests

promising to tell your biologic age, any

supplements claiming to reverse decades of wear

and tear, or influencers who say they've activated

telomerase. It sounds like science fiction. It

probably is. Telomeres aren't the hourglass of

life. They're mileage markers. They tell you where

you've been, not where you're going. So the best

way to protect them is a boring, proven way. Eat

plants and fish, move daily. Sleep well, don't

smoke. Keep your diet Mediterranean and your

expectations realistic. If you want to explore

real longevity science, join us for the

Mediterranean Longevity Cruise. In the summer of

2026. We'll have World class physicians,

scientists and a food network chef all sailing the

Mediterranean and talking about living longer and

better. No miracle molecules required. This has

been 4Q researched and written by me, Dr. Terry

Simpson, your chief medical explanationist. Audio

and editing done by Simpler Media and the pod God

of telomeres himself, Evo Terra. For references

shownotes, you can visit4q.com,

yourdoctorsorders.com and also go to my

substack@terry rsimpson.com and remember I am a

board certified physician but I am not your

physician. If you have medical concerns please see

your own board certified doctor and registered

dietitian, not a longevity doctor who is in a

functional medicine holistic nonsense. This

podcast is for your education entertainment. It is

not a prescription. Stay curious, stay skeptical,

keep your diet Mediterranean and hey to my

friend's daughter. We are so proud of you and what

you're doing and we are so happy that modern

science has kept you alive because you bring a lot

of joy to your parents living. I'm Dr. Simpson.

Have a good week everybody.

Hey Evo, do you remember when we thought time was

on our side? Turns out so did our Salomers. Good

thing we've still got wine, sunshine and maybe a

few base bears left to spare. At least I hope we

do. I've actually been thinking about getting an

extra set of base pairs. What do you think.