How does ageing work and how can you slow it down?

Ageing does not follow a smooth, gradual slope. Research involving nearly 52,000 people showed that the largest shifts in blood proteins occur around the ages of 41, 60 and 67. At the cellular level, DNA damage, poorly functioning mitochondria (the cell's energy factories) and protein clumping accumulate over time. At the same time, the chemical labels on DNA that determine which genes are switched on or off change in pattern. These pattern changes are so predictable that they function as a kind of biological clock, one that can even estimate the likelihood of disease and death.

One of the most visible consequences is low-grade, persistent inflammation, also known as 'inflammaging'. The body is, in a sense, perpetually on a low level of alert without any acute infection being present. This background inflammation increases the risk of cardiovascular disease and metabolic disorders. The gut microbiome plays an active role in this: an unfavourable composition of gut bacteria can release pro-inflammatory substances. Overeating works in the same way: a continuous caloric surplus causes a similar smouldering inflammation and thereby accelerates the biological ageing process.

Muscle loss is another concrete consequence of ageing. An estimated 3 to 24 percent of the population is affected by it to varying degrees. A combination of adequate high-quality protein, regular physical exercise and, where necessary, anti-inflammatory measures is the best-supported approach. Drugs that stimulate muscle growth, such as certain hormone-like substances or antibodies targeting inhibitors of muscle growth, are under investigation but have not yet been proven effective in humans.

For slowing ageing itself, the most promising approaches, such as partially 'resetting' cells to a younger state, removing senescent cells with so-called senolytics, and blood exchange between young and old individuals, have so far been tested exclusively in animal models. The step to humans has barely been taken. Five blood proteins have been identified as potential future drug targets through genetically supported analysis, but that too remains far from clinical application. Plant extracts such as berberine have only been studied in computer models and have no clinical evidence behind them.