Like mushrooms after a heavy rain, medical problems may pop up quickly, yet few people save money to deal with them. Some just can't afford it; others mistakenly think they'll be in great health for the rest of their lives.
Further, most Americans are unaware of the staggering amount of money they'll need to cover medical expenses through their retirement.
"We did a study that shows a couple aged 65 today would need $225,000 in post-tax savings to pay for health care expenses throughout their retirement," says Sunit Patel, a senior vice president and health care expert at Fidelity Investments in Boston.
Other studies suggest much more would be needed. A "low-risk" couple at age 65 should have about $635,000 saved for medical expenses, according to a May analysis by the Employee Benefit Research Institute.
If you're 45 today, the amount you'll need will be even higher when you turn 65 due to inflation. Costs for retiree medical benefits have been going up at about a 6 percent annual rate since 2004, according to Patel.
"It gives you an idea of the magnitude of dollars that we're talking about here," he says.