Most people over 65 are poorly nourished and eat too much salt, according to a study.
The 2013 study released by the Korea Centers for Disease Control and Prevention says six in every 10 elderly people took in more than the recommended daily dose of 2,000 mg of sodium.
"As people get older, their kidneys' ability to filter salt out of the body dwindles, so even a little more sodium can raise blood pressure rapidly," said Yoon Joon-hyung at Inje University's Sanggye Paik Hospital.
"Elderly people should pay special attention to their sodium intake, because they're exposed to the risk of cardiovascular and cerebrovascular diseases due to high blood pressure."
But the taste buds also weaken as people get older, making them more prone to add more salt to their food.
"An adult has an average of 245 taste buds, but an elderly person has only 88," Yoon said, so elderly people need about 3.5 times the salt as young people to taste it.
The result is a vicious cycle. "If you cut down on salt drastically when you're used to salty food, you could lose your appetite and become undernourished," he added. "It's best to reduce salt intake little by little so you can get used to the blander taste."