The puzzle of how some people live healthily for 100 years or more may have finally been answered by scientists.
Tests have shown that the blood of super-agers is stocked with unusually potent immune cells which personally attack viruses, bacteria or tumours.
Most people carry a type of cell known as CD4 T-cells, which mostly work like sentinels, scouting around for invaders, then pumping out chemicals to attract the ‘soldier’ immune cells which wipe out the disease.
But a study of seven supercentenarians – all of whom lived to 110 or older – found that a large number of their CD4 T-cells take up arms themselves against pathogens, giving a huge boost to the immune system.
Researchers found that the super-agers contained far more of those kinds of cell, around 25 per cent, compared with less than 10 per cent, for the average person.
Dr Kosuke Hashimoto, of the Riken Center for Integrative Medical Science (IMS), in Japan,said: “We were especially interested in studying this group of people, because we consider them to be a good model of healthy aging, and this is important in societies like Japan where aging is proceeding rapidly.”
“If we can find the link between the immune system and aging and longevity, we may be able to contribute to prolonging healthy life expectancies.”