Can you clear out "zombie cells" to slow down ageing?
The idea is biologically sound and produces impressive results in mice, but whether it works and is safe in people remains unknown. For now, exercise and a healthy diet are the most concrete and safe ways to influence this ageing process.
Senescent cells, also known as zombie cells, are cells that have stopped dividing but refuse to die. They release a cocktail of inflammation-promoting substances that damages surrounding tissues and has been linked to conditions such as atherosclerosis, liver scarring, osteoarthritis and diabetes. The more of these cells accumulate as we age, the greater the harm.
Wiping out zombie cells completely is not without risk, however. Earlier in life they actually protect against cancer, by stopping damaged cells from growing out of control. They also play a role in wound healing. A therapy that removes them indiscriminately therefore also dismantles a protective mechanism.
In animal studies, so-called senolytics are showing promise. These are substances that specifically push senescent cells into self-destruction. A peptide designed by researchers at Erasmus MC restored fur density, physical condition and kidney function in ageing mice, with no visible side effects. Immune cells engineered to target a protein on the surface of zombie cells (uPAR) cleared senescent cells in mice with lung cancer or liver scarring, with a clearly positive result. Both approaches have so far been tested in animals only.
In people, substances that clear zombie cells have not yet been convincingly proven to work. Studies in people are under way, but large studies with clear outcomes do not yet exist. There are also safety questions: at certain doses a shortage of blood platelets arose, raising the risk of bleeding. A practical problem is that there is no reliable way to measure zombie cells accurately in a living person, which makes it difficult to judge whether a treatment is working.
A gentler approach targets not the zombie cells themselves but the harmful substances they release. Well-known examples are metformin (a diabetes medicine) and quercetin (a substance found in apples and onions). The evidence for these in people is still thin. Regular exercise and eating less are also mentioned as ways to limit the damage caused by zombie cells, but here too strong evidence for specific recommendations is currently lacking.
This answer draws on several reviews and two studies not indexed separately. The underlying biology is well supported: that zombie cells cause damage is consistently described across the literature. The evidence for senolytics as a treatment comes almost entirely from animal studies. The researchers themselves point to the absence of reliable biomarkers, an unclear safety profile in people, and the lack of large studies in people as the main barriers to real-world use.
Can stem cell therapy slow down or cure rheumatoid arthritis?
Stem cell therapy may be able to slow the symptoms of rheumatoid arthritis, but it does not cure it. The research is still too limited for firm conclusions, so if you are interested, discuss it with your rheumatologist.
How do you safely taper off Ozempic?
Whether gradual tapering is better than stopping abruptly is not yet known, but stopping abruptly leads to weight regain and worsening of blood pressure and other values in most people. Always discuss a stopping plan with your doctor, especially if you are also using the medication for your heart or for diabetes.
Is retatrutide more effective than Ozempic?
Indirect comparisons suggest that retatrutide produces greater weight loss than semaglutide (Ozempic/Wegovy), but the drug has not yet been approved and no direct head-to-head trial exists. If you want to be treated now, semaglutide or tirzepatide are the available choices.
Is taking a stack of supplements at the same time dangerous?
Whether a supplement stack is smart or dangerous depends on which substances you combine and whether you also take medicines. Always tell your doctor or pharmacist what you are taking, and be especially careful with St John's wort and goldenseal.
What are the side effects of Ozempic?
Semaglutide causes digestive complaints, mainly nausea, in one in four users; these usually resolve over time. Rarer signals such as eye-nerve damage require medical follow-up, so always use this medication under the supervision of a doctor.
Does taking resveratrol make sense as an anti-ageing strategy?
For humans there is no convincing evidence that resveratrol supplements do anything against ageing; the animal research is interesting but has not yet translated into clinical practice, so hold off on supplements until better human data are available.