Recently, I met with top scientists at the FDA in Rockville, Maryland, discussing among other things, breastfeeding. It was their collective opinion that breastfeeding offered psychological nurturing benefits, but nothing more. No immunological factors, etc. Their logic was that all proteins are broken down by strong digestive enzymes. What do you think?
Robert Cohen - Oradell, New Jersey
I applaud the critical thinking and intellectual curiosity of these scientists. When immunoglobulins were first discovered in breast milk, the appealing and simple conclusion was drawn that these immunoglobulins would directly improve the immune status of the baby. Indeed, specific antibodies against respiratory and intestinal bacteria and viruses are found in human breast milk. These have been thought to increase a child’s resistance to infection. Apparently the aforementioned scientists have pointed out that this reasoning is overly simplistic. In fact, the strong digestive enzymes in the infant and the acid bath awaiting the antibodies in the stomach would tend to denature and digest these antibodies, rendering them useless.
While I admire their reasoning and believe that this line of thinking deserves further exploration, there are currently no good studies that prove that a baby’s digestive process renders all antibodies inactive. In fact, there are some studies that suggest a baby’s immature digestive system may allow antibodies to make it through the stomach intact.
Regardless of the controversy surrounding the fate of antibodies in the stomach, there is plenty of evidence that shows that breastmilk benefits babies. Therefore, I vehemently disagree with the conclusion that breast milk is essentially no different from formula.
Many studies comparing the frequency of illness between breast- and formula-fed infants have demonstrated fewer illnesses and less severe illnesses in breast-fed infants (Garza et. al Special Properties of Human Milk, Clinics of Perinatology 14:11-32, 1987). While it is very difficult to separate all of the variables of parenting style and environment, mounting evidence shows a striking reduction in the incidence and seriousness of gastrointestinal infections, respiratory infections, and ear infections in breast-fed babies (Duncan et. Al Exclusive Breast Feeding for at Least Four Months Protects Against Otitis Media, Pediatrics 91:867-872 1993.) In evaluating the benefits of breast milk, the American Academy of Pediatrics conducted a review of the literature for evidence of disease reduction with the use of human milk. In their policy statement on breastfeeding, they found “strong evidence” that breast milk reduces the incidence and/or severity of diseases such as diarrhea, lower respiratory infections, ear infections, bacterial meningitis, and urinary tract infections. (American Academy of Pediatrics Policy Statement on Breastfeeding and the Use of Human Milk, Pediatrics 115(2):496-506, 2005)]. A review of data from the 1988 National Maternal and Infant Health Survey (NMIHS) showed that mortality rates are decreased 21% in breastfed infants beyond the newborn period (Pediatrics, 113(5):e435-e439, 2004). Other studies have shown a decrease in non-infectious diseases such as eczema and asthma. (Journal of Pediatrics, 139(2):261-266, 2001). If the immunoglobulins are rendered useless by digestion, how could this be?
Apart from the specific properties that I have mentioned above, it is important to emphasize that breast milk is a dynamic fluid that changes in composition throughout the day and throughout the course of lactation. It provides for the baby the specific nutrients that are needed at each age and in each situation. The early data about breast milk was obtained from the pooled breast milk of many mothers. At that time it was not understood how unique human breast milk is for each individual infant (Lawrence, P.B. Breast Milk, Pediatric Clinics of North America, Oct. 1994). (Breast milk tastes different from feeding to feeding, which is another advantage over formula, as it prepares babies for the wide variety of foods to which they will be exposed in the future.)
The suggestions you heard from these prominent scientists serve as a good reminder that the mysteries of this dynamic fluid have not, by any means, been fully deciphered. Nevertheless, it becomes clearer year by year, that human milk is precisely designed for human babies. There may well be other important micro-nutrients or factors that we don’t even have instruments to measure yet. Not many decades ago, immunoglobulins were unknown. While formulas are an excellent alternative when breast feeding is not possible, human breast milk is the superior food for human babies for many, many reasons.