The government plans to set a numerical goal for the first time to rein in the number of people with dementia, with an eye to reduce such patients in their 70s over the next six years, government sources said Wednesday.

The move is aimed at curbing an increase in social security expenses by promoting prevention and delaying the onset of the disease. The government plans to state its goals in a new outline of policies to tackle dementia to be released this summer, they said.

The government will hold a meeting with experts in fields related to the disease Thursday and present the plan, the sources said.

Under current policies, the government places emphasis on creating a society where people can live comfortably even if they develop dementia, which involves a decline in cognition including memory loss.

But under the plan the government will also begin to focus on prevention, as a health ministry estimate predicts some 7 million people, or one out in five aged 65 or above, will suffer from dementia in 2025 amid the country's rapidly aging society.

As of 2012, dementia patients accounted for about 4 percent of people between the ages of 70 to 74 and the rate of such patients aged 75 to 79 was around 14 percent, according to a government estimate.

Specific measures for disease prevention include holding exercise lessons at local community centers, as it has been found that physical activity and social engagement could help prevent the disease, the sources said.

At the same time the government will promote research of the disease, as current scientific evidence on preventing dementia is insufficient, the sources said.

In 2015, the government compiled a national strategy to support dementia patients by organizing local "dementia supporters," people who have knowledge of the disease and are able to provide help to sufferers and their families.