To Your Health
Are people who were not breast-fed lacking in any important nutrients?
A. The science of nutrition is not yet sophisticated enough to answer this intriguing question. Even the question of whether the incidence of certain diseases in adulthood is reduced by breast-feeding is difficult to answer. For instance, research suggests but does not prove that breast-feeding in infancy is associated with a small reduction in the risk of heart disease in adulthood.
While it is reasonable to assume that early life events have an influence on a person's health in adulthood, it is more likely that there is an accumulation throughout life of many incidents, favorable or unfavorable, that affects our well-being. However, the effect of breast-feeding on intelligence does seem to be well-documented. An article in the prestigious Journal of the American Medical Association (May 8, 2002, pp. 2365-2371) came to the conclusion that the longer an infant is breast-fed, the better they score on intelligence tests as adults. In light of what we know about the effect of one of the omega-3 fatty acids (docosahexaenoic acid or DHA) on brain development in infancy, this observation is reasonable. DHA is present in breast milk but, until recently, not in infant formulas.
We may not be able to control what happens to us during infancy, but once we are adults we may be able to overcome the inadequacies of our formative years. One aspect of this greater control in adulthood is the food choices we make each day of our lives, and even when our food choices are imperfect, in America we usually have access to food supplements. A probiotic supplement would not be classified as a nutrient though it is a way of improving our nutritional status.
Probiotics are live microorganisms that live in the gut and benefit their host. Probiotics promote healthy digestion, influence nutrient absorption, and act like a natural antibiotic by inhibiting the growth of disease-causing microorganisms. There are 400-500 different kinds of microorganisms that ordinarily inhabit our gut from an early age, and most are members of the Lactobacillus family, with Lactobacillus reuteri (L. reuteri) being one of these. Different strains of L. reuteri are found in various animal species (mice, pigs, etc.) but the strains found in human breast milk are most "at home" in the human gut.
The population of probiotic organisms shifts during development. Infants and younger children have different strains of intestinal organisms than adults, and so organisms such as Bifidobacteria infantis in babies will be gradually replaced by Lactobacillus acidophilus by about age 5. The advantage of L. reuteri is that it provides benefits from infancy into adulthood. Most of the research with L. reuteri is done with preschool children, and supplements do appear to decrease the number of days with fever and other indications of illness. In addition, adults appear to benefit from L. reuteri supplements, with about half the number of sick days compared to a group that did not receive the supplements.
Inoculation with a quality probiotic like L. reuteri is a definite advantage to an infant, and there may be other yet unrecognized benefits to breast-feeding.