For young and middle-aged adults, snacking can be the enemy of the waistline. As people age, however, their calorie intake tends to drop, either from appetite loss, medical conditions or difficulty buying food. This puts some older adults at risk of inadequate nutrition and unintended weight loss.

Research suggests that even among relatively healthy people in their 60s and beyond, those with low calorie, protein and carbohydrate intakes die sooner.

In the new study, published in the Journal of the American Dietetic Association, researchers found that snacks were an important source of older adults' daily calories and nutrients. And in general, snackers took in more calories, protein, carbohydrates and fat than non-snackers did.

While that could be a problem for other age groups, the extra nutrients might benefit elderly men and women, according to the study authors.

Older adults who notice that they've lost weight, or that their appetite has waned, might want to add some snacks to their daily menu, said lead author Dr. Claire A. Zizza, an assistant professor of nutrition at Auburn University in Alabama.

She and her colleagues based their findings on data from a national health and nutrition survey that included 2,000 adults age 65 and older. Overall, 84 percent said that they snacked in addition to eating meals.

On average, snacks accounted for one-quarter of the study participants' daily calories and carbohydrates, and 14 percent of their protein. Snackers ate about 250 calories more each day than non-snackers did.

That doesn't mean that older adults should have a couple bowls of potato chips each day for the sake of their health, according to Zizza.

People should avoid "empty calories," she told Reuters Health, and instead choose healthful snacks like fruits, vegetables, yogurt, tuna and whole grains.

On the other hand, older adults who are eating a nutritionally sound diet shouldn't feel they have to give up their potato chips or desserts, Zizza noted.

"Favorite foods can be a great source of pleasure," she said.