美国国家公共电台 NPR--Can multivitamins improve memory? A new study shows 'intriguing' results

Can multivitamins improve memory? A new study shows 'intriguing¹' results

Transcript²

Americans spend billions of dollars on supplements each year, and roughly 1 in 3 adults report taking a multivitamin. But there is a debate about whether this helps promote good health.

A team of researchers wanted to assess how a daily multivitamin may influence cognitive³ aging and memory. They tracked about 3,500 older adults who were enrolled⁴ in a randomized controlled trial. One group of participants took a placebo⁵, and another group took a Silver Centrum multivitamin, for three years. The participants also took tests, administered online, to evaluate memory.

At the end of the first year, people taking a multivitamin showed improvements in the ability to recall words. Participants were given lists of words — some related, some not — and asked to remember as many as possible. (List-learning tests assess a person's ability to store and retrieve⁶ information.)

People taking the multivitamin were able to recall about a quarter more words, which translates into remembering just a few more words, compared to the placebo group.

"We estimate that the effect of the multivitamin intervention⁷ improved memory performance above placebo by the equivalent of 3.1 years of age-related memory change," the authors write in their paper, which was published this week in the American Journal of Clinical Nutrition. And the authors point to a sustained benefit.

"This is intriguing," says Dr. Jeffrey Linder, chief of general internal medicine at Northwestern University Feinberg School of Medicine, who was not involved in the study. But he says the overall effect found in the study was quite small. "It seems like a pretty modest difference," Linder says. And he points out that the multivitamins had no effect on other areas of cognition evaluated in the study, such as executive function, which may be more important measures.

Study author Dr. JoAnn Manson, who is chief of the division of preventive medicine at Brigham and Women's Hospital, says this is not the first study to show benefits from multivitamins. She points to a study published last year in Alzheimer's & Dementia that showed participants who took a daily multivitamin performed better, overall, on global cognitive function on tests measuring story recall, verbal fluency⁸, digit⁹ ordering, as well as executive function.

"It is surprising that such a clear signal for benefit in slowing age-related memory loss and cognitive decline was found in the study, " Manson says. "Those receiving the multivitamin did better than those receiving the placebo."

Our bodies and brains require many nutrients¹⁰ for optimal¹¹ health and efficiency. Manson says if people have deficiencies in these nutrients it may influence memory loss or speed cognitive decline. So, she says taking a multivitamin may help someone prevent a deficiency if they're not getting all the nutrients they need from their diet.

"It's important to highlight that a multivitamin will never be a substitute for a healthy diet," Manson says, since micronutrients are typically better absorbed through foods than through supplements." But it may be a complementary approach or strategy for maintaining cognitive health among older adults," she says.

Linder says he will continue to tell his patients that if they eat a healthy diet they are unlikely to benefit much from a multivitamin. "If you're taking too much of a particular supplement and your body doesn't need it, you're just peeing it out," he says. He wrote an editorial, published in JAMA, arguing that vitamins and supplements could be a waste of money for a lot of people. He argues that we should help people adopt a better pattern of eating.

"Eating a diet that has plenty of fruits and vegetables is associated with longevity¹² and better function and better quality of life," Linder says. There's plenty of research to show a healthy diet is linked to better heart health, and when it comes to protecting cognitive function, "the current thinking is that all of the stuff that's good for your heart is also good for your brain," he says.

When Linder talks to his patients about healthy aging, he focuses on good sleep habits, physical activity and a healthy diet. "My big concern with all of the focus that people have on vitamins is that it's distracting them from things that actually will help them stay healthy," Linder says.

"If someone is taking a multivitamin, I'm not going to tell them to stop," says Dr. R. Sean Morrison, who is a geriatrician at Mount Sinai Health System in New York. But he says he would not encourage the use of multivitamins as a way to protect against memory loss, because he says the effects measured in the studies are not very convincing. "I don't think it's the magic bullet that people are looking for," Morrison says. When talking to his patients, he too focuses on the importance of healthy habits and good social relationships.

The study was funded, in part, by the National Institutes of Health and other grants. The vitamins were provided by Pfizer Inc. and Haleon, the makers¹³ of Centrum, the brand of multivitamins taken by participants in the study. The study authors say the funders had "no role" in the study design, analysis or interpretation¹⁴.

1 intriguing   

adj.有趣的；迷人的v.搞阴谋诡计(intrigue的现在分词)；激起…的好奇心

参考例句：

• These discoveries raise intriguing questions. 这些发现带来了非常有趣的问题。
• It all sounds very intriguing. 这些听起来都很有趣。 来自《简明英汉词典》

2 transcript   

n.抄本，誊本，副本，肄业证书

参考例句：

• A transcript of the tapes was presented as evidence in court.一份录音带的文字本作为证据被呈交法庭。
• They wouldn't let me have a transcript of the interview.他们拒绝给我一份采访的文字整理稿。

3 cognitive   

adj.认知的，认识的，有感知的

参考例句：

• As children grow older,their cognitive processes become sharper.孩子们越长越大，他们的认知过程变得更为敏锐。
• The cognitive psychologist is like the tinker who wants to know how a clock works.认知心理学者倒很像一个需要通晓钟表如何运转的钟表修理匠。

4 enrolled   

adj.入学登记了的v.[亦作enrol]( enroll的过去式和过去分词 )；登记，招收，使入伍（或入会、入学等），参加，成为成员；记入名册；卷起，包起

参考例句：

• They have been studying hard from the moment they enrolled. 从入学时起，他们就一直努力学习。 来自《简明英汉词典》
• He enrolled with an employment agency for a teaching position. 他在职业介绍所登了记以谋求一个教师的职位。 来自《简明英汉词典》

5 placebo   

n.安慰剂；宽慰话

参考例句：

• The placebo has been found to work with a lot of different cases.人们已发现安慰剂能在很多不同的病例中发挥作用。
• The placebo effect refers to all the observable behaviors caused by placebo.安慰剂效应是指由安慰剂所引起的可观察的行为。

6 retrieve   

vt.重新得到，收回；挽回，补救；检索

参考例句：

• He was determined to retrieve his honor.他决心恢复名誉。
• The men were trying to retrieve weapons left when the army abandoned the island.士兵们正试图找回军队从该岛撤退时留下的武器。

7 intervention   

n.介入，干涉，干预

参考例句：

• The government's intervention in this dispute will not help.政府对这场争论的干预不会起作用。
• Many people felt he would be hostile to the idea of foreign intervention.许多人觉得他会反对外来干预。

8 fluency   

n.流畅，雄辩，善辩

参考例句：

• More practice will make you speak with greater fluency.多练习就可以使你的口语更流利。
• Some young children achieve great fluency in their reading.一些孩子小小年纪阅读已经非常流畅。

9 digit   

n.零到九的阿拉伯数字，手指，脚趾

参考例句：

• Her telephone number differs from mine by one digit.她的电话号码和我的只差一个数字。
• Many animals have five digits.许多动物有5趾。

10 nutrients   

n.（食品或化学品）营养物，营养品( nutrient的名词复数 )

参考例句：

• a lack of essential nutrients 基本营养的缺乏
• Nutrients are absorbed into the bloodstream. 营养素被吸收进血液。 来自《简明英汉词典》

11 optimal   

adj.最适宜的；最理想的；最令人满意的

参考例句：

• What is the optimal mix of private and public property rights in natural resources?私人和国家的自然资源产权的最适宜的组合是什么？
• Optimal path planning is a key link for the sailing contest.帆船最优行驶路径规划是帆船比赛取胜的关键环节。

12 longevity   

n.长命；长寿

参考例句：

• Good habits promote longevity.良好的习惯能增长寿命。
• Human longevity runs in families.人类的长寿具有家族遗传性。

13 makers   

n.制造者，制造商（maker的复数形式）

参考例句：

• The makers of the product assured us that there had been no sacrifice of quality. 这一产品的制造商向我们保证说他们没有牺牲质量。
• The makers are about to launch out a new product. 制造商们马上要生产一种新产品。 来自《简明英汉词典》

14 interpretation   

n.解释，说明，描述；艺术处理

参考例句：

• His statement admits of one interpretation only.他的话只有一种解释。
• Analysis and interpretation is a very personal thing.分析与说明是个很主观的事情。