What can you expect from a longevity clinic in the Netherlands?

Longevity clinics often measure your 'biological age' using epigenetic clocks: they examine patterns in your DNA that are associated with ageing. In large population studies, such measurements predict things like mortality risk and physical functioning better than your date of birth alone. But what that score means for you personally has not yet been established. Several measurement methods are also in circulation, and scientists have not yet agreed on which is best. The score you receive therefore depends in part on the choice made by the clinic.

The most solid offering of a longevity clinic is a good exercise programme. A combination of cardiovascular training, strength training, balance and flexibility demonstrably improves physical functioning, counteracts muscle loss and bone density decline, reduces the risk of falls and raises quality of life. This holds true for frail older adults as well. How large the effect is depends on how well the programme is tailored to you. This is the best-supported intervention in longevity medicine.

For supplements and agents aimed at ageing mechanisms, such as senolytics (substances that clear out senescent cells), stem cell therapy or so-called 'longevity supplements', the picture is far less rosy. Hundreds of substances extend the lifespan of laboratory animals, but clinical studies in healthy humans are rare. Whether these agents do anything in people is largely unknown. Efficacy and safety have not been sufficiently studied for most of these treatments in healthy older adults.

Hormonal treatments, such as growth hormone, testosterone or thyroid hormone, are sometimes offered as rejuvenation therapies. Growth hormone in healthy older adults has no proven benefit and carries risks. Strict medical indications apply to other hormones. When they are prescribed outside those indications, the risks are considerable. If you have symptoms that may be hormonal in nature, discuss them with your own doctor before considering an expensive clinic treatment.

Caloric restriction and gut microbiome interventions are also attracting attention, but the evidence in humans is still limited and cannot yet be translated into concrete recommendations. In short: a longevity clinic can offer you valuable insights through biomarker measurements and can set up a good exercise programme. But for most other interventions they offer, it is wise to critically ask about the underlying evidence.