That estimate is based on a new study that found a higher lifetime risk than previously thought: After age 55, people have up to a 4 in 10 chance of eventually developing dementia—if they live long enough.

The risk of developing dementia in the United States is much higher than previously estimated, according to a new study published in the journal "Nature Medicine" on Monday. People in the United States are living longer,

Dementia cases in the U.S. are expected to double by 2060, with an estimated one million people diagnosed per year, according to a new study led by Johns Hopkins University and other institutions.

New research suggests that the risk for developing dementia is significantly higher than previously estimated, and the burden on the United States population will grow substantially over the next few decades.

Older studies estimated a lower risk of dementia. According to new research, the number of people living with the disease in the U.S. is expected to double by 2060.

New cases of dementia will double by 2060, when 1 million U.S. adults are projected to develop the memory-robbing condition each year, according to a new study.

The lifetime risk of dementia after age 55 is about 42% — more than double the risk reported by earlier studies, and one that puts greater urgency on the need to mitigate addressable health problems,

KTVU's Alex Savidge and Greg Lee sit down with Dr. Han Lee, Neurologist at Kaiser Permanente to talk about the latest findings on dementia and the increasing risk of developing the disease.