There are "serious gaps" in dementia research, which is slowing down the development of new treatments, a charity has said.
Few career opportunities and a lack of funding is leading to a shortage of doctors working in the field, the Alzheimer's Society warned.
Its report found that 70% of dementia PhD students leave the research area within four years, while five times more people are doing a PhD in cancer than dementia.
Despite the fact that most dementia patients rely heavily on social care, fewer than 2% of the most prolific UK dementia researchers specialise in social care and social work.
The Alzheimer's Society commissioned the study from the not-for-profit research firm Rand Europe.
It found that the lack of a secure career path for researchers, due to scarce funding, was putting people off.
It also found too few mid-level positions for post-doctoral researchers to help them move to their first independent research post.
Health professionals already working in areas such as social care are also unable to secure PhD posts or junior positions.
The charity said there was a "lingering view" that not much can be done for people with dementia.
Dr Doug Brown, director of research and development at the Alzheimer's Society, said: "Dementia research is going from strength to strength in the UK but this report highlights that there are still too few people choosing it as a career, especially those from clinical and care professions.
"We must build the reputation of dementia research to show that it is one of the most cutting edge areas of research that is poised to make significant advances in the next decade.
"By attracting and retaining more of the very best researchers in dementia, we will be able to significantly speed up progress towards innovative care and that all important cure."
Some 850,000 people in the UK have dementia, and the cost to the UK economy is put at £26.3 billion a year.
The charity Action on Smoking and Health (Ash) also published a report, endorsed by Public Health England, on the growing link between smoking and dementia.
Ash chief executive, Deborah Arnott, said: "Smokers know that smoking causes cancer and heart disease but they need to also know about the increased risk of developing dementia.
"Stopping smoking is the single most important way smokers can improve their health as well as reducing their risks of developing dementia."