Can aging be reversed? What has been tried, in people and in animals, how far each idea has got, and who is working on it. We gather and explain; we don't judge.
In mice, changing levels of certain molecules called transcription factors reversed some effects of aging. In old mouse livers, raising one of these molecules, EZH2, shifted gene activity toward a younger pattern and reduced fat buildup and scarring. That work carries a warning: these molecules affect many genes, so changing them can have unintended effects, and much more study is needed before use in people. In sea squirts, short electrical pulses extended life, with about 75% of treated animals alive and healthy a year later. Researchers say it is an open question whether the electrical approach can be applied to humans.
Sources: nih.gov: Manipulating gene activity to reverse aging ↗ · woods.stanford.edu: Electrical pulses reverse aging in sea squirts, offering clues for extending human longevity ↗
Biological age reflects the state of a person's body, not just the time since birth. One NIH article describes it as the damage that builds up across tissues and organs. People of the same calendar age can differ a lot in health, which is one reason the idea matters. A review notes there is no agreement on the best way to measure it, and different methods can give different results.
Sources: ncbi.nlm.nih.gov: New insights into methods to measure biological age: a literature review - PMC ↗ · nih.gov: Gauging biological age to predict future health ↗
Some small studies suggest biological age measures can go down, but the evidence is early. In a pilot trial of 43 healthy men aged 50-72, an 8-week diet and lifestyle program was linked to a 3.23-year lower DNA-based age than the control group. Within the treated group, the average drop was 1.96 years, which only showed a strong trend toward significance. In a separate analysis of clinical trial blood samples, three cycles of a fasting-mimicking diet were linked to a 2.5-year drop in median biological age. Harvard-led researchers found stress from surgery, pregnancy or severe COVID raised biological age signs, which were reversed after recovery. The authors note these clocks are biomarkers that may reflect biological age or could be driven by other factors not yet identified.
Sources: PubMed abstract: Potential reversal of epigenetic age using a diet and lifestyle intervention: a pilot randomized clinical trial. ↗ · PubMed abstract: Fasting-mimicking diet causes hepatic and blood markers changes indicating reduced biological age and disease risk. ↗ · news.harvard.edu: How dynamic is biological age? ↗
Public claims and headlines, quoted word for word from the article, next to how far research on what was tested has got. We don't judge the people or companies involved.
“Drug giants Eli Lilly and Novo Nordisk say patients taking their drugs age less quickly, according to readouts from molecular “aging clocks.”
Eli Lilly and Novo Nordisk · MIT Technology Review · Oct 6, 2026 · Read the article ↗
“Aging has a relatively simple explanation and is apparently reversible," wrote Sinclair.”
David Sinclair · MIT Technology Review · Jan 27, 2026 · Read the article ↗
“Our bodies hold a backup copy of our youth that can be triggered to regenerate, said Sinclair, the senior author of a new paper showcasing the work of his lab and international scientists.”
David Sinclair · CNN · Jan 12, 2023 · Read the article ↗
“Although the increase in lifespan was modest, the company says the research provides a demonstration of age reversal in an animal.”
Rejuvenate Bio · MIT Technology Review · Jan 9, 2023 · Read the article ↗
Researchers planned to compare a blood measure of biological age in women who did and did not have a live birth after IVF.
Original title: Epigenetic Clock to Predict Ovarian Aging and Live Birth in ARTResearchers tracked people over time to see if a biological age score predicted mild memory and thinking problems.
Original title: Association between Gompertz law-based biological age (GOLD BioAge) and incident mild cognitive impairment: Modifying role of social activeness.Some protein aging scores linked to death from any cause.
Original title: Systemic and organ-specific proteomic aging clocks as predictors of cancer incidence and survival: insights from the Finnish Twin CohortThis review looked at brain age scans and whether treatments can change them.
Original title: Turning Back the Ageing Clock? Brain Age in Neuroprotective and Clinical Interventions.Black and Hispanic adults were more likely to start work late than White adults.
Original title: Employment trajectories and biological aging: Racial and ethnic disparities in work instability and epigenetic age acceleration.This trial has not started and has no results yet.
Original title: Human Albumin Combined With Plasma Exchange for Frailty Intervention“TAME is not a moonshot. It’s not even about scientific achievement really, it’s more about political achievement. Metformin is a tool to get aging as an indication.”
“But it’s premature to make any clinical recommendations based on the results from our study. NMN needs to be tested in more people and for longer periods of time to determine if it has anti-ageing effects in humans,”
“Finding an effect in muscle tissue is very interesting and does demonstrate that NMN is not inert,”
“It mightn’t be wise to increase cellular entry of NMN, as an increased intracellular NMN/NAD + ratio activates SARM1, an executor of axon degeneration.”
“If you could help prevent multiple problems at the same time, like we think metformin may do, then that's almost the ultimate in preventative medicine,”
“Aging has a relatively simple explanation and is apparently reversible”
Companies in this area, in their own words, with their registered human trials. Listing a company is not an endorsement or investment advice.
“Alkahest, a Grifols subsidiary, is a research and drug discovery company mining the deepest layers of plasma knowledge to inform the development of potential transformative therapies and solutions for patients.” (from its website)
Registered human trials as lead sponsor: 12 (Phase 2, No phase). ClinicalTrials.gov ↗
We couldn't read a description from its website.
Registered human trials as lead sponsor: 9 (Phase 2, Phase 1, No phase). ClinicalTrials.gov ↗
“Our mission is said simply, yet it is quite ambitious. Calico is working to better understand the biology of aging and using those insights to advance foundational discoveries into potential medicines that enable people to lead longer and healthier lives.” (from its website)
Registered human trials as lead sponsor: 8 (Phase 1, Phase 2, No phase, Phase 1 and Phase 2). ClinicalTrials.gov ↗
We couldn't read a description from its website.
Registered human trials as lead sponsor: 7 (Phase 2, Phase 1). ClinicalTrials.gov ↗
“Life Biosciences is a biotechnology company pioneering cellular rejuvenation using epigenetic restoration to reverse diseases of aging.” (from its website)
Registered human trials as lead sponsor: 4 (Phase 1). ClinicalTrials.gov ↗
“Pioneering thymus regeneration and longevity research. Join us in the fight against age-related immune decline.” (from its website)
Registered human trials as lead sponsor: 1 (Phase 2). ClinicalTrials.gov ↗
“Early experiments have shown that the ability of cells to resist stressors that give rise to disease can be restored. At Altos, we are focused on understanding how we can translate this science to help people live healthier lives.” (from its website)
No human trials registered on ClinicalTrials.gov as lead sponsor.
“Cambrian Bio is developing drugs targeting the underlying drivers of the metabolic decline and dysfunction experienced by every person.” (from its website)
No human trials registered on ClinicalTrials.gov as lead sponsor.
“Juvenescence is a clinical-stage drug development company dedicated to extending healthy lifespan through innovative medicines” (from its website)
No human trials registered on ClinicalTrials.gov as lead sponsor.
“At Loyal, our approach is to help dogs live longer and stay healthier as they age by developing drugs that target the underlying processes that lead to age-associated disease and disability.” (from its website)
No human trials registered on ClinicalTrials.gov as lead sponsor.
“NewLimit is inventing medicines to add healthy years to people's lives.” (from its website)
No human trials registered on ClinicalTrials.gov as lead sponsor.
“Targeting the root causes of aging to create life-changing treatments for chronic conditions affecting both companion animals and humans.” (from its website)
No human trials registered on ClinicalTrials.gov as lead sponsor.
“Retro Biosciences develops therapies that meaningfully reverse age-related diseases.” (from its website)
No human trials registered on ClinicalTrials.gov as lead sponsor.
We couldn't read a description from its website.
No human trials registered on ClinicalTrials.gov as lead sponsor.
This is general information gathered from the sources listed, not medical advice. Talk to your doctor before starting anything new.
