Eating leafy greens, dark orange and red vegetables and berry fruits, and drinking orange juice may be associated with a lower risk of memory loss over time in men, according to a study published in the November 21, 2018, online issue of Neurology, the medical journal of the American Academy of Neurology.
"One of the most important factors in this study is that we were able to research and track such a large group of men over a 20-year period of time, allowing for very telling results," said study author Changzheng Yuan, ScD, of Harvard T.H. Chan School of Public Health in Boston. "Our studies provide further evidence dietary choices can be important to maintain your brain health."
The study looked at 27,842 men with an average age of 51 who were all health professionals. Participants filled out questionnaires about how many servings of fruits, vegetables and other foods they had each day at the beginning of the study and then every four years for 20 years. A serving of fruit is considered one cup of fruit or ½ cup of fruit juice. A serving of vegetables is considered one cup of raw vegetables or two cups of leafy greens.
Participants also took subjective tests of their thinking and memory skills at least four years before the end of the study, when they were an average age of 73. The test is designed to detect changes that people can notice in how well they are remembering things before those changes would be detected by objective cognitive tests. Changes in memory reported by the participants would be considered precursors to mild cognitive impairment. The six questions include "Do you have more trouble than usual remembering a short list of items, such as a shopping list?" and "Do you have more trouble than usual following a group conversation or a plot in a TV program due to your memory?"
A total of 55 percent of the participants had good thinking and memory skills, 38 percent had moderate skills, and 7 percent had poor thinking and memory skills.