Does eating green salads every day slow cognitive decline?
According to a study by researchers at Rush University Medical Center in Chicago, eating one serving of leafy green vegetables a day may assist in preserving memory and thinking as a person ages. The study was published in the Dec. 20 issue of Neurology.
"Adding a daily serving of green leafy vegetables to your diet may be a simple way to help promote brain health,” said study author Martha Clare Morris, ScD, a nutritional epidemiologist at Rush. “There continue to be sharp increases in the percentage of people with dementia as the oldest age groups continue to grow in number. Effective strategies to prevent dementia are critically needed.”
The study was part of the Rush Memory and Aging Project, which began in 1997 with resident volunteers from Chicago-based retirement communities and senior public housing complexes. A food-frequency questionnaire was added from 2004-2013, and almost 1,000 enlisted volunteers, those without dementia, from the aforementioned project answered the questionnaires, along with receiving at least two cognitive assessments for the analyses of cognitive change.
Individuals who ate one serving of green leafy vegetables, the study results showed, had a slower rate of decline on tests of memory and thinking skills than people who rarely or never ate them. Additionally, the study found that older adults who ate at least one serving of leafy green vegetables showed an equivalent of being 11 years younger cognitively. The serving size in the study was half-cup servings of either spinach, kale, collards or greens, or a one-cup serving of lettuce/salad.
Adding leafy green vegetables to the diet anyway promotes optimal health benefits. The vitamin K in these green vegetables protect bones from osteoporosis and helps prevent inflammatory diseases. Additionally, because of the high content of antioxidants, leafy green vegetables are considered among the best cancer-preventing foods. More benefits of leafy greens include good skin, eye and brain health; aid to the immune system; and a source of fiber to regulate the digestive system.
“The study results do not prove that eating green, leafy vegetables slows brain aging, but it does show an association,” Morris said. “The study cannot rule out other possible reasons for the link. And, because the study focused on older adults with the majority of participants being White, the results may not apply to younger adults and to people of color. The results need to be confirmed by other investigators in different populations and through randomized trials to establish a cause-and-effect relationship between the eating of leafy greens and reductions in the incidence of cognitive decline," Morris said.