Key TakeawaysDementia is expected to double worldwide within the next 25 yearsNew cases will rise from 11.4 million in 2023 to 24.7 million in 2050Women and poorer nations will bear the brunt of this "global health crisis".WEDNESDAY, Oct. 14, 2026 (HealthDay News) — Dementia cases are set to double within the next 25 years worldwide, warns a new study.There are expected to be 24.7 million new cases of dementia by 2050, up from 11.4 million in 2023, researchers reported Oct. 12 in the journal JAMA Neurology."In terms of the scale, obviously, this number of new dementia cases is staggering,” said Dr. Liron Sinvani, director of research and innovation at the Northwell Institute for Healthy Aging and professor at the Feinstein Institutes for Medical Research in New York.“This is not a future problem,” added Sinvani, who was not involved in the research. “It's an accelerating epidemic crisis that demands immediate attention.”Women and people living in poorer nations are expected to be at greater risk from dementia, researchers concluded.“Greater vigilance in dementia screening among women, alongside the prioritization of women’s brain health and sex-specific risk factors, is needed,” concluded the research team led by Ashleigh Vella, a postdoctoral research fellow at the University of New South Wales in Australia.For the new study, researchers pooled data from 22 previous studies spanning nearly 40,000 people across 18 countries and six continents.Results showed that dementia cases will likely more than double, as the global population ages."Why is this happening? It's driven by the aging population,” Sinvani said. “We know that dementia rates increase as people age. So, the statistics we like to use [are] that after age 65, about 1 in 9 people have dementia, but after 85, it could be almost 1 in 3."Researchers also projected more dementia in women compared to men, with 18 cases per 1,000 persons versus 10.6 cases. These numbers held even after the team adjusted for age.“Women are disproportionately affected, and this was not just because they live longer,” Sinvani said.Instead, the research team suggested several different factors that might increase dementia risk among women.For example, Alzheimer’s disease is more frequent in women, researchers said. The hormonal changes linked to menopause might play a role, as might metabolic factors that affect heart health.Geography plays a part too, with cases expected to grow more quickly in low- and middle-income countries compared to high-income countries.“The rate of new dementia cases was 64% higher in low- and middle-income countries compared to high-income countries,” Sinvani said. “Basically, what we're saying is that the countries that have the fewest resources for diagnosis, treatment and caregiving are the ones that are going to be facing this enormous wave of dementia cases. And they have very limited infrastructure to respond." These projections indicate a global health crisis, Sinvani concluded.“Health systems must prepare for this massive increase in diagnostic and care demand, and this is especially true for these low- and middle-income countries where the growth will be fastest,” Sinvani said. “We know that dementia care requires a lot of caregiver support and is very costly. We will need a better infrastructure.”A focus on dementia prevention might help mitigate these dire predictions, Sinvani added.“We know that there are 14 established modifiable risk factors that account for nearly half of cases. Every health system and every individual have to put in the work here,” Sinvani said.“We need to improve education, physical activity and obesity. We need to manage blood pressure, diabetes and cholesterol. We really need to be promoting physical activity, social engagement, education, and reducing smoking and air pollution. These are all things that can modify the trajectory of what we're facing,” Sinvani concluded.More informationThe Centers for Disease Control and Prevention has more on reducing risk for dementia.SOURCES: JAMA Neurology, Oct. 12, 2026; Dr. Liron Sinvani, director of research and innovation at Northwell Institute for Healthy Aging and professor at Feinstein Institutes for Medical Research.What This Means For YouDementia rates are expected to rise, but certain lifestyle measures like healthy eating and exercise can help reduce your risk. .Sign up for our weekly HealthDay newsletter