Eating foods included in two healthy diets -- the Mediterranean or the MIND diet -- is linked to a lower risk for memory difficulties in older adults, according to a study published in the Journal of the American Geriatrics Society.

The Mediterranean diet is rich in fruits, vegetables, whole grains, beans, potatoes, nuts, olive oil and fish. Processed foods, fried and fast foods, snack foods, red meat, poultry and whole-fat dairy foods are infrequently eaten on the Mediterranean diet.

The MIND diet is a version of the Mediterranean diet that includes 15 types of foods. Ten are considered "brain-healthy:" green leafy vegetables, other vegetables, nuts, berries, beans, whole grains, seafood, poultry, olive oil, and wine. Five are considered unhealthy: red meat, butter and stick margarine, cheese, pastries, sweets and fried/fast foods.

Researchers examined information from 5,907 older adults who participated in the Health and Retirement Study. The participants filled out questionnaires about their eating habits. Researchers then measured the participants' cognitive abilities -- mostly on their memory and attention skills.

The researchers compared the diets of participants to their performance on the cognitive tests. They found that older people who ate Mediterranean and MIND-style diets scored significantly better on the cognitive function tests than those who ate less healthy diets. In fact, older people who ate a Mediterranean-style diet had 35% lower risk of scoring poorly on cognitive tests. Even those who ate a moderate Mediterranean-style diet had 15% lower risk of doing poorly on cognitive tests. The researchers noted similar results for people who ate MIND-style diets.

This study suggests that eating Mediterranean and MIND-style diets is linked to better overall cognitive function in older adults, said the researchers. What's more, older adults who followed these healthy diets had lower risks for having cognitive impairment in later life, noted the researchers.