Links tighten between IQ, breast-feeding

母乳喂養的孩子智商更高

Mǔrǔ wèiyǎng de háizi zhìshāng gèng gāo

Links Tighten Between IQ, Breast-Feeding

新近一項研究得出結論稱,延長母乳喂養期可使孩子更加聰明.該研究發表于美國醫學會主辦的《美國醫學會雜志•兒科學》上.

Breast-feeding longer can make children smarter. That's the conclusion of a study published Monday in JAMA Pediatrics, a journal of the American Medical Association.

就許多方面而言,這項研究并不會讓母乳喂養的提倡者感到意外,他們在很早之前就提出母乳喂養與認知能力之間存在關聯,現在他們只不過是又多了一項支持他們論點的研究.對于那些持懷疑態度的人,他們則可能會堅持認為最重要的是嬰兒母親的智商,或是認為針對母乳喂養的社會壓力會導致家長不堪重負,而這本身會給孩子的發育帶來麻煩.然而,目前這些研究發現可能會給公共健康倡議者推動提高母乳喂養比例的行動提供強有力的支持.美國疾病控制與預防中心的數據顯示,母乳喂養的比例在嬰兒出生伊始為75%左右,但在嬰兒一周歲時便降低至25%的平均水平.

In many ways, the study won't surprise proponents of breast-feeding, who have long posited a connection between nursing and cognition and now have an additional piece of research to back up their argument. Skeptics could likely stick to the view that what matters most is how smart a baby's mom is, or that social pressure to breast-feed can have its own problems for children's development by creating stressed-out parents. However, the findings are likely to add muscle to public-health advocates' push to increase breast-feeding rates, which start out around 75% but slump to an average of 25% at a baby's first birthday, according to the Centers for Disease Control and Prevention.

這項研究并不是最早將母乳喂養與智商水平聯系在一起的研究,但研究人員稱它的實驗樣本大,而且它還排除了嬰兒母親的智商及孩子接受的教育等變量,因此更加讓人信服.該研究的第一作者、哈佛醫學院的兒科學助理教授曼迪•貝爾福特指出,以往的研究在對可能影響孩子智商的其他因素進行調整方面存在問題,而且它們的實驗樣本較小, 或是未考慮到母乳喂養期的時間長短.

The JAMA study isn't the first to study a link between nursing and intelligence, but researchers say it is more conclusive because of its size and how it has isolated variables such as the mother's IQ and the child's upbringing. Previous studies have had difficulty adjusting for other factors that might influence a child's IQ, were limited by their small size or didn't account for length of nursing, said Mandy Belfort, the JAMA study's lead author and assistant professor of pediatrics at Harvard Medical School.

新近這項研究根據他們可接觸多少書籍等因素調查了每個孩子的生活環境,并對每個孩子的母親進行了智商測試.他們還針對可能影響智商的因素提出了詳細的問題,比如兒童保健、家庭收入及父母的教育程度等,然后利用統計模型剔除這些因素.貝爾福特稱,她希望他們得出的是母乳喂養與智商之間的真實聯系.

The latest study examined and rated each child's environment based on factors such as how many books are available, and gave each mother an IQ test. They also asked detailed questions about factors that might influence IQ, such as child care, income and parental education. They then subtracted those factors using a statistical model. Dr. Belfort said she hopes that 'what we have left is the true connection' with nursing and IQ.

她指出,母乳喂養很難通過隨機性的實驗進行研究,因為把一部分孩子分在非母乳喂養組是不道德的行為,所以研究人員只能選擇像她所展開的那種觀察性研究.從1999年至2010年期間,波士頓兒童醫院的研究人員對1,312名嬰兒及他們的母親進行了跟蹤研究.他們要找出其中有多少孩子在一周歲時依然在吃母乳,然后分別在這些孩子三歲和七歲時對他們進行智商測試.

Breast-feeding is hard to study in a randomized trial because it is unethical to put some children in the non- group, Dr. Belfort said, which leaves researchers with observational studies such as the one she conducted. Researchers at Boston Children's hospital followed 1,312 babies and mothers from 1999 to 2010. They found out how many of those children were still consuming their mothers' milk at their first birthday, and then tested the children's intelligence at ages 3 and 7.

那些在一周歲后依然吃母乳的孩子,他們在三歲時的語言理解能力測試中得分更高,這表示他們對所聽到的話的理解能力要高于喝配方奶的同齡人.到七歲時,母乳喂養的孩子在口頭及非口頭智商測試中的得分也更高.

Children who were still nursing after a year had higher receptive language scores at age 3, which means they understood what was being said to them better than their formula-fed peers. At age 7, the breast-fed children scored higher on verbal and nonverbal intelligence tests.

貝爾福特稱,一整年的母乳喂養可使孩子的智商分值比非母乳喂養的孩子高出四分左右,考慮到智商的平均分值大約為100分,這算得上一個大幅提升.這只是針對在飲食中會吃些母乳的孩子而言,那些在大約六個月大、開始食用固體食物之前只吃母乳的孩子具有更大的智商優勢.

A full year of nursing would boost a child's IQ by about 4 points over a child who didn't nurse, said Dr. Belfort, a significant bump considering that IQs average around 100. That is for children getting some breast milk in their diets; those consuming only breast milk before starting to eat solid foods around six months of age saw even greater advantages.

詞語解釋

母乳喂養 （mǔrǔ wèiyǎng） breast-Feeding

提倡者 （tíchàng zhě） proponent

支持 （zhīchí） back up

兒科 （érkē） pediatrics

隨機 （suíjī） randomize

(Source: myechinese.com)