Nearly 8 trillion won ($7.15 billion) was used in medical expenses for more than 11 million diabetes patients in the past five years, a lawmaker said Wednesday.

A total of 11.79 million people received medical treatment for diabetes and diabetic complications with the costs amounting to 7.89 trillion won in the 2011-2015 period, In Jae-keun of the main opposition Minjoo Party of Korea said, citing data of the National Health Insurance Service submitted to the National Assembly.

The number of diabetes patients jumped from 2.19 million in 2011 to 2.55 million in 2015, the data showed.

The medical expenses also jumped from 1.43 trillion won to 1.81 trillion won during the cited period, the data showed, adding that the 2015 figure account for 3.2 percent of total costs covered by the national health care insurance.

With the diet habits of South Koreans becoming "westernized," diabetes rates are growing. Other causes include overeating, drinking and stress, medical doctors say.

"Diabetes has become one of the chronic illnesses on the rise and the World Health Organization declared war against the disease," said Rep. In, adding that the government should come up countermeasures to fight the disease.

South Korea ranked as the seventh-lowest country in terms of the diabetes mortality rate among member nations of the Organization for Economic Cooperation and Development (OECD). (Yonhap)