What Zombie Cells Mean for Your Health

These inactive cells are lingering inside, but finding out more about them could drive new treatments for everything from Alzheimer’s to osteoarthritis

Kristen Fischer,

AARP

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Published October 27, 2025

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It may sound like something out of a horror movie, but zombie cells really are hanging out in our bodies like cellular sleepwalkers.

Zombie — or senescent — cells are those that are alive yet no longer divide and can release harmful substances into your body.

The scary part: The dormant cells, which get their name from the biological process of cell aging called senescence, may drive cancer and play a part in other ailments like sarcopenia, osteoarthritis, Alzheimer’s disease, cardiovascular disease, atherosclerosis, pulmonary disease, neurodegeneration and metabolic disorders. They can also weaken your immune system and hoard your energy.

Don’t be too spooked, though, because zombie cells — at least in some phases — could have an upside for your health.

Senescence is a critical mechanism by which our body defends against the growth and spread of cancers and tumors.

They can also play a positive role in some aspects of wound healing. Some research shows the zombie cells can be embedded in healthy tissue, so they may promote repair in damaged tissue by stimulating the growth of stem cells.

The science on zombie cells is progressing quickly, and researchers are studying how to remove the harmful zombie cells while keeping the productive ones. Soon, we could see more therapies that target the cells that, are linked to diseases. There’s also some research that says lifestyle factors — things as simple as regular workouts and ample sleep — may prevent damage that the cells can cause.

All about cellular aging

Zombie cells can emerge throughout our lives, but we accumulate more of them with age, and our immune systems are less effective at getting rid of them as we get older, explains Nathan LeBrasseur, director of the Robert and Arlene Kogod Center on Aging and an aging researcher at Mayo Clinic in Rochester, Minnesota.

Getting Serious About Senescent Cells

Research on the topic is growing quickly to identify the types of cells and their markers, which can equip scientists to pinpoint specific cells with effective therapies. A group of researchers formed the Cellular Senescence Network, or SenNet, to map out the cells in humans and mice.

Zombie cells are generally more beneficial in the short term, since the acute aging stage facilitates tissue repair, but over time, they lead to tissue dysfunction, among other disadvantages.

Senescent cells are not all bad, says Ana Catarina Franco, a postdoctoral fellow at the Kogod Center on Aging. Therefore, simply destroying all zombie cells may not be the best solution to battling disease. Some experts say killing the zombie cells is a potential anti-aging strategy, but researchers are still figuring out how to spot the senescent cells that cause problems and determine how exactly to destroy them without wiping out viable, healthy cells.

Uncovering senescent cells

Researchers already know that senescent cells differ based on where they are in our bodies. For example, the ones in your muscles aren’t the same as the ones in your skin.

When a skin cell goes into senescence (zombie mode), it results in three different subtypes, research out earlier this year in Science Advances found.

A team examined skin cells from 50 healthy donors ranging in age from 20 to 89. The samples included healthy cells and zombified ones. The researchers recorded images of the cells, coming up with 87 different characteristics to help group the cells.

Overall, they found drugs can target certain subtypes of zombie cells but not others. The researchers still want to know which subtypes are harmful or helpful, but their findings show that the problematic cells can be terminated.

Eyes on zombie cells

Another study out this year detailed how scientists could view the cells via magnetic resonance imaging (MRI) and potentially target and kill them with senolytic therapies or senotherapeutics. Some drugs, including metformin, rapamycin, resveratrol and spermidine, have exhibited potential in inhibiting senescence, according to the study. Some of these therapies might be able to be used alone or with others (along with lifestyle interventions) to address the obesity epidemic and metabolic diseases.

Formulating drugs that can stop the zombie cells from making proteins that resist dying is a focus of current research aimed at treating and perhaps reversing diseases. Blocking the proteins could force the cells to die off. Gene therapy can also kill senescent cells, so medications aren’t the only option.

But again, things may not be as simple as just killing all the zombie cells. Researchers are trying to home in on specific cells or biomarkers that come from them to target only the cells that are responsible for disease. In fact, a Sept. 19 study in Aging Cell describes a new method to tag the cells using molecules that researchers call aptamers, which are parts of synthetic DNA that can attach themselves on the cell's surface. In mice, researchers were able to spot DNA sequences that can latch on to proteins on the surface of cells and flag the zombie cells.

Death to the zombie cell

There are many ways these targeted therapies may affect older adults. Senolytic therapies could address diabetic macular edema — a condition that occurs when high blood sugar causes swelling in the retina that can lead to blindness. Typically, doctors treat it with a cancer drug to slow down blood vessel growth, but a drug called foselutoclax was able to stop a protein in zombie cells that resists death without destroying the healthy cells. In limited trials, the drug showed the potential to improve vision. Some animal research has shown that senolytic drugs can reverse osteoarthritis, as the medications can destroy the zombie cells so the body can heal itself. Research is being done to see how these drugs could be used to treat osteoporosis.

Preventing cells from becoming zombies

Some research showed that endurance exercise lowered the burden from zombie cells in mice. In healthy older adults, exercise lowered the amount of senescence biomarkers the cells released, according to LeBrasseur’s 2021 study in Aging Cell.

Last year, a study from LeBrasseur in The Journals of Gerontology Series A examined blood samples and noted that the senescence process likely plays a part in age-related functional decline and physical limitations — but physical activity appears to counter that process. In it, the researchers noted that more activity was associated with a reduction in biomarkers linked to senescence.

“There is very compelling evidence that supports foundational elements to healthy aging, including a healthy diet and physical exercise, can prevent the accumulation and even promote the clearance of senescent cells throughout the body,” LeBrasseur says. Healthy sleep patterns promote the cellular damage repair, too, he adds.

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Kristen Fischer is a contributing writer at AARP based at the Jersey Shore. She has also written for Health, WebMD, and McKnights and is the author of Zoo Zen: A Yoga Story for Kids.