For women, healthy diets may help with mobility when aging

The findings are published online and will appear in the July issue of the Journal of Nutrition.

"Little research has been done on how diet impacts physical function later in life. We study the connection between diet and many other aspects of health, but we don't know much about diet and mobility, " says Francine Grodstein, ScD, senior author of the study and a researcher in the Channing Division of Network Medicine at BWH. "We wanted to look at diet patterns and try to learn how our overall diet impacts our physicial function as we get older. "

Researchers examined the association between the Alternative Healthy Eating Index, a measure of diet quality, with reports of impairment in physical function among 54,762 women involved in the Nurses' Health Study. Physical function was measured by a commonly used standard instrument every four years from 1992 to 2008 and diet was measured by food frequency questionnaires, which were administered approximately every four years beginning in 1980.

The data indicate that women who maintained a healthier diet were less likely to develop physical impairments compared to women whose diets were not as healthy. They also found a higher intake of vegetables and fruits, a lower intake of sugar-sweetened beverages, trans-fats, and sodium, and a moderate alcohol intake, were each significantly associated with reduced rates of physical impairment. Among individual foods, the strongest relations were found for increased intakes of oranges, orange juice, apples and pears, romaine or leaf lettuce, and walnuts. However, researchers noted specific foods generally had weaker associations than the overall score, which indicates that overall diet quality is more important than individual foods.

"We think a lot about chronic diseases, cancer, heart disease, and tend not to think of physical function. Physical function is crucial as you age; it includes being able to get yourself dressed, walk around the block, and could impact your ability to live independently," says Kaitlin Hagan, ScD, MPH, first author and a postdoctoral fellow at BWH.

Future research is needed to better understand dietary and lifestyle factors that influence physical function.