Can epigenetic reprogramming reverse ageing?
Animal studies show that epigenetic reprogramming measurably reverses ageing. That step has not yet been taken in people, because the most widely used method carries a cancer risk. Exercise and a Mediterranean diet, however, have already been shown to influence biological age.
Partial reprogramming using so-called Yamanaka factors effectively reverses ageing in cells in animal studies. The idea is to temporarily return cells to a more youthful state without fully converting them into stem cells. That final step is dangerous: full reprogramming raises the risk of tumours, which makes direct use in people unfeasible for the time being.
Researchers are therefore looking for alternatives. Four newly discovered factors targeting processes such as protein production and energy metabolism reduced signs of ageing in cells grown in the lab, without the dangerous side effects of Yamanaka factors. This has only been shown in lab-grown cells, so how much benefit this would offer in people remains unknown.
A completely different approach that has been tested in people is plasma exchange: blood is partly replaced and topped up with antibodies. In a small study of 42 participants, this treatment clearly improved fifteen of the biological age clocks measured, compared with a dummy treatment. These clocks use chemical tags on your DNA to estimate how old your cells appear biologically. The study was small and the follow-up short, so more research is needed before firm conclusions can be drawn.
Exercise also works at this level. Both strength training and endurance training alter the chemical tags on your DNA. Active older adults show a slower rate of biological ageing through these measurements than inactive people of the same age. This is the most immediately actionable finding from the available research.
Diet likely plays a role as well. A Mediterranean diet was linked to a lower biological age in one study, and eating patterns that reduce bodily inflammation were associated with better protection of the end caps on your DNA strands in several studies. These are associations, however, and do not prove that the diet itself is the cause.
This answer draws on a mixed body of evidence. The Yamanaka reprogramming technique is well supported by research in cells and in lab animals, but has not been demonstrated in people. The blood plasma exchange study is the only one conducted in people with a dummy-treatment comparison group, but it included only 42 participants and had a short follow-up. A large-scale analysis of more than 15,000 human chemical-tagging profiles across 17 tissues provides a solid map of how ageing shows up in our DNA, but says nothing about cause and effect. The findings on exercise and diet are based on a combined analysis of multiple studies and a review article; the human evidence is weaker than data from lab animals. Diet studies did not always fully account for other factors that could explain the results. For the newly discovered rejuvenating factors, only data from cells grown in a lab is available.
Can you influence your epigenetic age through diet?
Multiple studies show that a healthy dietary pattern can favourably influence your epigenetic age, although these are surrogate measurements and results from smaller studies are sometimes clouded by conflicts of interest. A Mediterranean or plant-based diet rich in vegetables, nuts and vegetable oils has the most supporting evidence.
Can you really lower your biological age, and does research support this?
There are promising hints that biological age is measurable and perhaps steerable, but this has not been proven. Wait for larger studies in people before basing major decisions on this.
How reliable is an epigenetic age test?
An epigenetic age test provides a meaningful indication of biological ageing, but is not yet a definitive verdict on your health. Use the result as a starting point for a conversation with your doctor, not as a fixed judgement.
How quickly can you change your biological age with exercise?
Regular moderate to vigorous exercise is associated with a biological age that comes out 1 to 3 years lower, and molecular changes in muscles are measurable after just a few weeks. Whether a lower score on an epigenetic clock truly means living healthier or longer has not yet been proven: treat it as an encouraging signal, not a guarantee.
Do people age through different organs?
Yes, people age through different organ pathways. The science needed to map this precisely for each individual is promising, but still at an early stage.
Can fasting turn back your biological age?
Fasting, particularly intermittent fasting and ketogenic diets, moves multiple biological ageing markers in a favourable direction. Whether this truly translates into a younger biological age over the long term has not yet been proven, but you can already start with a fasting method that suits you.