Age is the greatest known risk factor for dementia — though it seems to go beyond the number of candles on the birthday cake.

New research out of the UK reports that biological age , the age of our organs, tissues and cells, plays a major role in dementia risk.

“Our findings suggest that biological aging data can help identify individuals at risk of dementia before clinical symptoms emerge,” lead study author Julian Mutz of King’s College London said in a statement .

Dementia is the progressive erosion of cognitive function. Several million Americans have it, while several million more are expected to develop it.…