For Amy Forstadt, the first six weeks of breast-feeding were a nightmare.
"I have pretty sensitive skin, and my baby was just a chomper," said Forstadt, a 37-year-old writer from Beachwood Canyon. Lactation consultants and a pediatric orthopedist were unable to detect a problem with Benjamin's "latch," so she wound up pumping milk to feed him from a bottle for the first month and half -- a cumbersome but, for her, less painful approach. That solution collapsed one night when the family dog devoured part of her breast pump, forcing her to nurse while her tears of agony splashed on Benjie's face.
Forstadt stuck with the nursing -- with the help of a different lactation consultant -- in large part so that her son could get the health benefits of breast milk. He's now 6 months old, and Forstadt loves breast-feeding him.
But the truth about the health benefits of breast-feeding is more complicated than most people realize.
This spring, the federal Agency for Healthcare Quality and Research (AHRQ) published a report that evaluated the research on breast-feeding and children's health. Assembling the data involved a year and a half of combing through more than 9,000 studies and reviews, selecting those that met strict quality criteria.
For The Record
Los Angeles Times Thursday, December 06, 2007 Home Edition Main News Part A Page 2 National Desk 1 inches; 25 words Type of Material: Correction
Breast-feeding: An article in Monday's Health section said a mother had consulted a pediatric orthopedist about her difficulties breast-feeding. She consulted a pediatric occupational therapist.
For The Record
Los Angeles Times Monday, December 10, 2007 Home Edition Health Part F Page 8 Features Desk 1 inches; 28 words Type of Material: Correction
Breast-feeding: An article in the Dec. 3 Health section stated that a mother had consulted a pediatric orthopedist about her difficulties breast-feeding. She consulted a pediatric occupational therapist.
Dr. Ruth Lawrence, who chairs the breast-feeding task force of the American Academy of Pediatrics (AAP), said the result is the "most comprehensive, all-inclusive" document on breast-feeding in developed countries. "It's an excellent report," she said.
The report didn't address the role of breast-feeding in developing countries, where infant formula mixed with tainted water is often deadly. It focused instead on countries such as the United States, where the effects are less dramatic -- and more difficult to measure.
The researchers found that breast-fed babies had fewer ear, gastrointestinal tract, and severe lower respiratory tract infections than formula-fed ones and were less prone to sudden infant death syndrome (SIDS), obesity, Type 1 and Type 2 diabetes, childhood leukemia, early-childhood asthma and atopic dermatitis (a skin disorder that causes eczema).
Though the reductions were as large as 72% (for severe lower respiratory tract infections), the report states that none of its findings imply causality.
This inability to prove cause and effect is a problem that plagues virtually all breast-feeding research. The problem is that women who breast-feed, as a whole, are very different from their bottle-feeding counterparts: wealthier, older and more educated, for starters. Although researchers are able to adjust their results for such factors, there's no way to adjust for every difference. Women who breast-feed are probably more health-conscious in numerous ways, which could explain why breast-fed children tend to be healthier.
The evidence is more suggestive in some areas than in others. "It's well proven that breast-feeding is effective at reducing infections in the newborn period, as long as children continue to be breast-fed," said Dr. Lawrence Gartner, past chairman of the AAP's breast-feeding group. The reason is that breast milk contains antibodies and other agents that prevent bacteria, toxins and viruses the baby has swallowed from attaching to the lining of the throat and gut.
He said that the research was "not nearly as good" for the other claims. One reason is that fewer studies have been done; another is that how breast milk might offer protection is less clear.
For example, scientists know that breast-fed babies are less likely to die of SIDS. Although much of this difference is explained by the fact that women who breast-feed tend to be more affluent and less likely to smoke cigarettes, not all of it is.
"I'm convinced about the benefits of breast-feeding against SIDS," said Dr. Michael Kramer, a professor of pediatrics and of epidemiology and biostatistics at McGill University in Montreal. One explanation, he said, is that breast milk might offer some protection by warding off respiratory illness.
But scientists aren't sure what causes SIDS. A leading hypothesis is that some babies are born with a brain stem abnormality that affects their ability to respond when they're not getting enough oxygen. The AHRQ researchers point out that babies who are prone to SIDS may also have difficulty with breast-feeding -- which could explain the difference in SIDS rates between breast-fed and bottle-fed babies.
In some cases, health differences may be related to the bottle itself. For example breast-fed babies may be less likely to be obese later in life because overzealous bottle-feeding -- "working the baby" until a bottle is empty -- interferes with babies' ability to stop eating when they're full, said Dr. Laurence Grummer-Strawn, chief of maternal and child nutrition for the Centers for Disease Control and Prevention.