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March 21, 2012

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Feeding babies on demand may improve IQ

March 21, 2012
Courtesy of the University of Essex
and World Science staff

Ba­bies who are fed when­ev­er they want may lat­er per­form bet­ter in school than those who were fed on a sched­ule, new re­search sug­gests.

The find­ing is based on the re­sults of in­tel­li­gence tests and school-based stand­ard­ized tests car­ried out be­tween the ages of five and 14. The IQ scores of eight-year-old chil­dren who had been demand-fed as ba­bies were four to five points high­er than the scores of sched­ule-fed chil­dren, the stu­dy found. IQ tests are a meas­ure of in­tel­li­gence de­signed to ex­press the dif­fer­ence be­tween a per­son’s in­tel­li­gence and the av­er­age in­tel­li­gence for their age group, roughly as a per­cent­age.

The find­ings are pub­lished in the Eu­ro­pe­an Jour­nal of Pub­lic Health.

The study was car­ried out by re­search­ers at the In­sti­tute for So­cial and Eco­nom­ic Re­search at the Uni­vers­ity of Es­sex, U.K., and at the Uni­vers­ity of Ox­ford. But the re­search­ers urged cau­tion in in­ter­pret­ing the find­ings.

“We must be very cau­tious about claim­ing a caus­al link be­tween feed­ing pat­terns and IQ. We can­not de­fin­i­tively say why these dif­fer­ences oc­cur, al­though we do have a range of hy­pothe­ses. This is the first study to ex­plore this ar­ea and more re­search is needed to un­der­stand the pro­cesses in­volved,” said Ma­ria Ia­covou, who led the re­search from the Uni­vers­ity of Es­sex.

Tak­ing in­to ac­count a wide range of back­ground fac­tors that in­clude par­ents’ educa­t­ional lev­el, family in­come, the child’s sex and age, ma­ter­nal health and par­ent­ing styles, the re­search found that demand-feed­ing is as­so­ci­at­ed with high­er IQ scores at age eight, and this dif­fer­ence is al­so ev­i­dent in the re­sults of stand­ard­ized tests at ages five, sev­en, 11 and 14. The study found that sched­uled feed­ing times did have ben­e­fits for the moth­ers, how­ev­er, who re­ported feel­ings of con­fi­dence and high lev­els of well-be­ing.

“The dif­fer­ence be­tween sched­ule and demand-fed chil­dren is found both in breast­fed and in bottle-fed ba­bies,” said Ia­covou.

“The dif­fer­ence in IQ lev­els of around four to five points, though sta­tis­tic­ally highly sig­nif­i­cant, would not make a child at the bot­tom of the class move to the top, but it would be no­tice­a­ble. To give a sense of the kind of dif­fer­ence that four or five high­er IQ points might make, in a class of 30 chil­dren, for ex­am­ple, a child who is right in the mid­dle of the class, ranked at 15th, might be, with an im­prove­ment of four or five IQ points, ranked higher, at about 11th or 12th in the class.”

The chil­dren of moth­ers who had tried but failed to feed to a sched­ule were found to have si­m­i­lar test scores as demand-fed ba­bies, Ia­covou said, which is no­ta­ble be­cause they would be ex­pected to do worse based on their moth­ers’ typ­i­cal de­mograph­ics. “It seems that it is ac­tu­ally hav­ing been fed to a sched­ule, rath­er than hav­ing the type of moth­er who at­tempted to feed to a sched­ule (suc­cess­fully or not) which makes the dif­fer­ence,” she said.

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Babies who are fed whenever they want may later perform better in school than those who were fed on a schedule, new research suggests. The finding is based on the results of intelligence tests and school-based standardized tests carried out between the ages of five and 14. The IQ scores of eight-year-old children who had been demand-fed as babies were four to five points higher than the scores of schedule-fed children, said the study. IQ tests are a measure of intelligence designed to express the difference between a person’s intelligence and the average intelligence for their age or category, roughly as a percentage. The findings are published in the European Journal of Public Health The study was carried out by researchers at the Institute for Social and Economic Research at the University of Essex, U.K., and at the University of Oxford. But the researchers urged caution in interpreting the findings. “We must be very cautious about claiming a causal link between feeding patterns and IQ. We cannot definitively say why these differences occur, although we do have a range of hypotheses. This is the first study to explore this area and more research is needed to understand the processes involved,” said Maria Iacovou, who led the research from the University of Essex. Taking into account a wide range of background factors that include parents’ educational level, family income, the child’s sex and age, maternal health and parenting styles, the research found that demand-feeding is associated with higher IQ scores at age eight, and this difference is also evident in the results of standardized tests at ages five, seven, 11 and 14. The study found that scheduled feeding times did have benefits for the mothers, however, who reported feelings of confidence and high levels of well-being. “The difference between schedule and demand-fed children is found both in breastfed and in bottle-fed babies,” said Iacovou. “The difference in IQ levels of around four to five points, though statistically highly significant, would not make a child at the bottom of the class move to the top, but it would be noticeable. To give a sense of the kind of difference that four or five higher IQ points might make, in a class of 30 children, for example, a child who is right in the middle of the class, ranked at 15th, might be, with an improvement of four or five IQ points, ranked higher, at about 11th or 12th in the class.” The children of mothers who had tried but failed to feed to a schedule were found to have similar test scores as demand-fed babies, Iacovou said, which is notable because they would be expected to do worse based on their mothers’ typical demographics. “It seems that it is actually having been fed to a schedule, rather than having the type of mother who attempted to feed to a schedule (successfully or not) which makes the difference,” she said.