TUESDAY, June 23, 2009 (HealthDay News) -- If you eat a healthy diet, you're likely to live longer.
It might be trite advice, but a new study offers proof that it can make a difference in your longevity.
Those with the best diets reduced their risk of death by up to 25 percent over a 10-year follow-up, said study author Ashima Kant, a professor of nutrition at Queens College of the City University of New York.
Kant and her colleagues extracted information from a National Institutes of Health/AARP database including more than 350,000 men and women, evaluating the link between dietary habits and their risk of death during the follow-up period. They divided the participants into five groups, depending on how closely they followed the 2005 USDA Dietary Guidelines for Americans.
"If you had the highest fifth of these scores, your risk of dying over the follow-up period was 20 to 25 percent lower," Kant said. She found gender differences, with women eating the healthiest reducing their risk of death by 25 percent and men reducing it by 20 percent.
"We have been advocating these kinds of behaviors for a while," she said. Other studies have found a survival benefit but have tended to look only at individual foods, she said. "This gets at looking at all these dietary features in a collective way," she said.
Kant's team asked the participants about six components of a healthy diet, including intake of fruits, vegetables, low-fat dairy, whole grains, lean meat and poultry, and fat.
People didn't have to eat perfectly to get a top score, she said. For instance, "if a person had five or six servings of vegetables a week, that would get them the top score [for that question]," she said.
"It's not that you have to do everything [recommended under the dietary guidelines] to have any health benefits," she said, noting that participants in the groups with lower (but not the lowest) scores also tended to live longer. For instance, women who were in the second-from-the-highest group on dietary scores were 20 percent less likely to die and men in that group were 17 percent less likely.
The study is published in the July issue of The Journal of Nutrition.
Good dietary habits may also help delay the progression of hardening of the arteries, according to a separate study published in the July issue of the The American Journal of Clinical Nutrition. Researchers from Tufts University and Wake Forest University evaluated the effect of a good diet on the progression of coronary artery disease in 224 postmenopausal women who had the disease when they enrolled in the Estrogen Replacement and Atherosclerosis Study. The better the diet, the slower the progression of disease, they found.
"Both studies are finding similar things," said Penny Kris-Etherton, a distinguished professor of nutrition at Penn State University, who wrote an editorial to accompany the atherosclerosis study.
"We're getting more and more evidence that diet [when poor] can play a key role in chronic disease development, progression and all-cause mortality," she said.
Will the findings -- especially the fact that those who got the top benefit didn't eat perfectly -- inspire people?
"As a nutritionist, you try to be optimistic and hope so," Kris-Etherton said. "But society sometimes makes it difficult. We live in an environment where there are so many food choices that aren't consistent with our [dietary] guidelines."
To learn more about the dietary guidelines, visit the U.S. Department of Health and Human Services.