绿菜与大脑健康

诸平

绿菜富含人体健康需要的多种物质，常吃绿菜有益健康是众人所知的常理，但是，你每天一盘绿菜，可以使大脑延缓衰老11年，你相信吗？请看看美国拉什大学医学中心（Rush University Medical Center）的最新报道，或许可以得到答案。

拉什大学是从一个拉什医学院发展到今天拥有包括护理学院、健康卫生学院、研究生学院等4个学院的大学。它是一所私立大学。当时只有22名学生（December 4, 1843）、16个星期的课程，其中1898-1942年附属于芝加哥大学（University of Chicago），后独立大学。经过一百多年的发展，到目前有在校学生超过4500名，员工近8000人，在伊利诺伊州芝加哥地区有很高知名度的医学类大学。拉什大学其实是医科大学，主要从事医疗临床、医学教育、医学基础科研的大学，在世界大学的排名很靠后，在我们国内也没有知名度，这说明它的基础医学科研相对落后。但它还是有多门学科跻身全美国大学排名前30名，如社区公共卫生护理系（第5名）、精神病学（第6名）、儿科学护理系（第7名）、听力学（第9名）等等。它在伊利诺伊州芝加哥地区有很高知名度，有赖于它的医学中心(拉什大学医学中心)，这个医学中心就是大学的附属医院，它创建于1837年3月初。拉什大学医学中心位于芝加哥市中心的西部，和高速公路、地铁的蓝线、粉红线相邻，其中粉红线穿越医院，有多条公共汽车停靠站在附近。这个医学中心位于伊利诺伊州的医疗区域的东北角，伊利诺伊州的医疗区域主要由四家医院组成。有拉什大学医学中心、，伊利诺伊州立大学(UIC)医学中心、JESSE BROWN医学中心、库克郡医院。还有退伍军人医疗部门、库克郡卫生管理部门、伊利诺伊州红十字会等单位。

拉什大学医学中心排名情况：

In 2016 U.S. News & World Report ranked Rush University Medical Center as #2 in Illinois, #2 in Chicago metro area and one of the top hospitals in 9 different medical specialties nationally including:

• cancer (#38)

• diabetes and endocrinology (#46)

• ear, nose, and throat (#25)

• geriatrics (#11)

• gynecology (#21)

• nephrology (#19)

• neurology and neurosurgery (#13)

• orthopedics (#4)

• urology (#38).^[3]

One serving of leafy greens a day may slow brain aging by 11 years

December 20, 2017, Rush University Medical Center

While cognitive abilities naturally decline with age, eating one serving of leafy green vegetables a day may aid in preserving memory and thinking skills as a person grows older, according to a study by researchers at Rush University Medical Center in Chicago. The study results were published in the December 20, issue of Neurology, the medical journal of the American Academy 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 continues 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 results suggest that people who ate one serving of green, leafy vegetables had a slower rate of decline on tests of memory and thinking skills than people who rarely or never ate them. The study results also suggest that older adults who ate at least one serving of leafy green vegetables showed an equivalent of being 11 years younger cognitively.

960 older adults completed food questionnaires and received annual cognitive assessments

The study enlisted volunteers already participating in the ongoing Rush Memory and Aging Project, which began in 1997 among residents of Chicago-area retirement communities and senior public housing complexes. A "food frequency questionnaire" was added from 2004 to February 2013, which 1,068 participants completed. Of them, 960 also received at least two cognitive assessments for the analyses of cognitive change.

This study involved these 960 people, who at the study start were an average age of 81 years old and did not have dementia. They had their thinking and memory skills tested every year and were followed for an average of 4.7 years. The participants also completed the food frequency questionnaire, which assessed how often and how many half-cup servings they ate of either spinach; kale/collards/greens; or a one-cup serving of lettuce/salad.

The study divided the participants into five groups based on how often they ate green leafy vegetables, and compared the cognitive assessments of those who ate the most (an average of about 1.3 servings per day) and those who ate the least (0.1 servings per day).

Overall, the participants' scores on the thinking and memory tests declined at a rate of 0.08 standardized units per year. Over 10 years of follow-up, the rate of decline for those who ate the most leafy greens was slower by 0.05 standardized units per year than the rate for those who ate the least leafy greens. This difference was equivalent to being 11 years younger in age, according to Morris.

More research needed in younger and minority populations

The results remained valid after accounting for other factors that could affect brain health, such as seafood and alcohol consumption, smoking, high blood pressure, obesity, education level and amount of physical and cognitive activities.

"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."

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 leafy greens and reductions in the incidence of cognitive decline, Morris said.

Explore further: Lots of leafy greens might shield aging brains, study finds