Dr. Henri Roca & a Whole-Person Approach to Food Sensitivities, Intolerance, & Allergies

Emerging Concepts

Emerging concepts are innovative ideas or interventions which are surfacing and hold potential for eventual adoption into clinical practice. IFM has a strong history of successfully identifying and accelerating the acceptance of emerging concepts. We are pleased to bring you this monthly update, to keep you in-the-know on exciting innovations in Functional Medicine.

The microbiome has been a burgeoning area of study within the medical research community for over a decade, with the initiation of the Human Microbiome Project by the National Institutes of Health in 2007.^[1] But the idea that there are a variety of microbes living on and in the human body is not itself a new concept: “I then most always saw, with great wonder, that in the said matter there were many very little living animalcules, very prettily a-moving,” wrote Antonie van Leeuwenhoek (1632-1723), one of the first scientists to study the human microbiome.^[2]

Could the mother’s lifestyle affect her child’s microbiome? What factors influence a pediatric microbiome, and how might they lead to health or disease? These are just some of the myriad questions asked by scientists in the field, which will be explored in the sections below, along with several significant caveats.

The Pediatric Intestinal Microbiome

The intestinal microbiome may evolve with the human host over its entire lifespan—from conception to death—and, as such, it is a cause for speculation into the development of health and disease.^[8] Conception to the first year of life is considered to be the intestinal microbiome’s early-life “critical window”—a time when it is most vulnerable to environmental influences.^[2,9] Some scientists posit that early-life environmental exposures alter the development of the microbiome, and that these changes may shift the immune system toward a hypersensitive and/or hyperinflammatory state.^[2,9]

Maternal-to-Fetal Microbial Transfer: In-Utero Hypothesis

Many scientists are investigating the validity of an in-utero hypothesis, which proposes that the fetus is exposed to microbes from the mother’s placenta, amniotic fluid, and umbilical cord.^{[10-12,14-16]}

Some studies suggest the infant gut colonization process may be initiated prenatally by a distinct microbiota in the mother’s placenta and amniotic fluid^{[2,10,12,17,18]} but other scientists are questioning whether the placenta has a distinct microbiome at all. Scientists questioning the in-utero hypothesis point out the likelihood of contamination and the lack of suitable controls to evaluate this contamination, as well the difficulty of proving the significance of the bacteria detected in the amniotic fluid and placenta. Additionally, research to date has been mostly conducted using molecular methods, which may not be appropriate for the study of low-abundance microbial communities.

Caveats & Concerns Within the Literature & in the Field

Research into the pediatric intestinal microbiome is in its early stages and continues to expand. While there is evidence that the makeup of the pediatric microbiome may have lasting consequences on health, it is important to note some caveats and concerns within the current literature—first and foremost, there is a wealth of variability among healthy microbiomes. Researchers in this field are often the first to point out that they are still largely in the dark about what makes microbiomes different from one another, let alone whether one is healthier than another.^[32]

Challenges within the field include:

• Making sense of the data – Microbiome studies yield vast amounts of data with huge variability, 33-35 and several external factors may also impact this variability.^[35]
• Getting the right data – Many of the techniques used to characterize bacteria may not be precise enough.^[33]

• Risk of contamination – There is a current controversy underway whereby some scientists believe the placenta has its own microbiome, which may help create the neonatal microbiome. Others believe the placenta does not have its own distinct microbiome but is contaminated by the vaginal microbiome during birth.^[34,36,37]