King, a professor of family medicine at the Medical University of South Carolina, is one of several researchers who have proven in recent years that it's never too late to get healthy -- and that adopting better habits even in midlife translates to less disease and a longer life.

King led a recent study that evaluated the cardiovascular effects of adopting healthier habits in middle age -- what he calls the "turning back the clock study."

And surprise! It works. What's more, you don't have to be fanatical, but the more healthy habits you adopt, not surprisingly, the healthier you become.

King and his colleagues evaluated almost 16,000 men and women who were between the ages of 45 and 64 when the Atherosclerosis Risk in Communities Study began. The researchers looked specifically at four heart-healthy habits: eating at least five servings of fruits and vegetables a day; exercising at least 2.5 hours a week; keeping a healthy weight; and not smoking.

During four years of follow-up, the researchers found that those who adopted the four healthy habits were 40 percent less likely to die and 35 percent less likely to suffer heart problems than those who did not adopt the beneficial habits. The findings were published in The American Journal of Medicine.

Stephanie Chiuve, a research associate at Harvard School of Public Health, and her colleagues led a similar study that included almost 43,000 middle-aged and older American men who were part of the Health Professionals Follow-up Study. The goal: to see if a healthy lifestyle is linked with a lower risk of heart disease, even among those who take high blood pressure medication or cholesterol medication.

The researchers looked at basically the same collection of healthy habits that King evaluated in his study, with some additions. "We looked at whether the diet was rich in not only fruits and vegetables but also whole grains, fish, chicken and other poultry and unsaturated fats -- like vegetable oils and nuts," Chiuve said. They also looked at whether participants smoked; got exercise for 3.5 hours a week at a moderate pace; consumed alcohol moderately; and kept a healthy body weight.

All were free of chronic heart disease in 1986, when the study began, and the men were ages 40 to 75.

Like King's team, Chiuve's team found that healthy habits make a big difference. Men who adopted healthy habits during the study period, from 1986 to 2002, had a lower risk of heart disease compared to men who didn't change their overall number of healthy habits.

"For each additional habit you added, the benefit increased," Chiuve said. Men who adopted one healthy habit had a 54 percent lower risk of heart disease, for instance, while those who embraced four had a 78 percent reduction in risk, she said.

"For the men who followed all five, they had an 87 percent lower risk of heart disease than the men who followed none," Chiuve said. The study was published in the journal Circulation.