Published: 21:54 BST, 7 August 2026 | Updated: 23:59 BST, 7 August 2026<\/p>\n
Modern medicine has transformed our chances of surviving many of the diseases that once cut lives short, from heart disease and diabetes to many forms of cancer.<\/p>\n
There is still no cure, few treatments that can slow its progress, and the number of people living with the disease is rising relentlessly.<\/p>\n
And while it remains overwhelmingly a disease of old age, affecting nearly one in three Americans aged 85 and over, that is no longer the whole story.<\/p>\n
A growing number of people are now being diagnosed in their 50s or even 40s \u2013 while they are still building careers, raising children and, in many cases, caring for ageing parents.\u00a0<\/p>\n
Many have yet to walk their children down the aisle or welcome grandchildren.<\/p>\n
And unlike in older patients, the first signs of what is known as early-onset dementia are not always memory lapses.<\/p>\n
Instead, the disease may first reveal itself through sudden personality changes, difficulty finding words, poor judgement or an unexpected struggle to cope with everyday tasks at work.<\/p>\n
Jana Nelson was 50 when diagnosed with early onset dementia, following severe personality changes and a sharp cognitive decline that left her unable to solve simple math problems or name colors<\/p>\n
With diagnoses of dementia in under-65s rising by as much as 200 percent between 2013 and 2017, researchers are racing to understand why.<\/p>\n
Greater awareness of the condition may partly explain the rise. But mounting evidence suggests lifestyle factors \u2013 including obesity, smoking, diabetes and poor sleep \u2013 may also play a role, with the roots of the disease stretching back decades before symptoms first appear.<\/p>\n
So what's really driving this worrying surge, and what can you do to lower your risk? We asked the experts what is driving the trend \u2013 and what it means for you.<\/p>\n
Dementia is an umbrella term for a group of disorders that cause memory loss and a gradual decline in thinking and reasoning, with Alzheimer's disease accounting for most cases.<\/p>\n
The condition is caused by the build-up of abnormal proteins in the brain that gradually destroy nerve cells, particularly in areas responsible for memory, language and decision-making.<\/p>\n
By far the biggest risk factor is age \u2013 after 65, the likelihood of developing dementia doubles every five years. But of the seven million Americans living with the condition, around 350,000 are under the age of 65, many of them in their 40s and 50s.<\/p>\n