Bifidobacterium – The inside scoop on baby’s first bacteria!

Bifidobacterium is the major genus of bacteria in the large intestine or colon. This important type of probiotic was first isolated way back in 1899 from the poop of breastfed babies! These days, there are at least 32 known species of Bifidobacterium, including B. infantis, a key species that first colonises the gut of infants.

Did you know? Bifidobacteria require a temperature of 36-38 degrees Celsius for optimal growth in humans. They also favour a pH of around 4.5-8.5, below or above which no growth occurs. These bacteria are gram-positive, nonmotile, and typically branched anaerobic bacteria. This means they don’t need oxygen to survive and thrive, cannot move on their own, and have no outer cell membrane, relying instead on a thick layer of peptidoglycan to stay intact.

Baby’s first bacteria!

Most babies first acquire Bifidobacteria during vaginal delivery. Bifodobacteria quickly take up residence in a newborn’s gut and help to support healthy gut development and digestion right from the get-go.

Research shows that babies born vaginally have a dramatic increase in certain species of Bifidobacteria in the first three days after birth. In contrast, Bifidobacteria levels remain significantly lower in babies born by C-section until a week after birth, assuming the baby is breastfed (Makino, 2018).

Early colonisation of the infant gut by Bifidobacteria is thought to protect against a range of diseases in later life. For formula-fed babies born by C-section, it might take longer to establish healthy colonies of beneficial bacteria in the gut. In one study, formula-fed babies had lower levels of Bifidobacteria and significantly higher proportions of Bacteroides, Clostridium coccoides and Lactobacillus (Fallani et al., 2010).

The evidence suggests that the human gut microbiome stabilises over time, with differences subsiding around one month of age and little difference remaining at one year old between babies born vaginally and babies born by C-section (Stockholm et al., 2016).

A critical window for Bifidobacteria

Despite babies’ microbiomes evening out over time, those early days and weeks seem to have an outsize effect on long-term health.

For instance, rates of obesity and diabetes remain significantly higher in babies born by C-section (Yuan et al., 2016). Similarly, the use of antibiotics in the first six months of life has been linked to changes in rates of obesity and overweight at age seven (Ajslev et al., 2011).

There’s also some evidence that children are more likely to have asthma at the age of seven if they had less diversity in gut microbes in the first week and first month of life (Abrahamsson et al., 2014).

All of this has led some researchers to suggest that there is a ‘critical window’ for seeding a healthy gut microbiome in infants. Because of these concerns, several infant formulas feature Bifidobacteria and other probiotics. It’s also why many parents, especially those of formula-fed, C-section babies, choose to use probiotics specially designed for infants.

Probiotics in pregnancy

Because bacteria are transmitted from mother to baby during delivery and in pregnancy, it’s helpful to maintain a healthy, balanced gut microbiota in pregnancy. This can support your baby’s delicate balance of gut bacteria in those first few days and weeks, which can set them in good stead for a healthy life.

There’s also some evidence that your microbiome might affect your baby even before birth. Scientists used to think that the womb was a sterile place, with babies getting a ‘clean slate’ at birth. There’s increasing evidence that this isn’t the case, and that bacteria do transfer into amniotic fluid, with the placenta enjoying a unique microbiome all of its own (Aagaard et al., 2014; Stenson et al., 2017).

Probiotics such as Bifidobacteria and Lactobacilli have generally been found to be safe during pregnancy and may even help combat bacterial vaginosis (BV) in pregnancy (Dugoua et al., 2009). Always check with your doctor before taking any supplement if you are pregnant or nursing an infant.

References

Aagaard, K., Ma, J., Antony, K. M., et al. (2014). The placenta harbors a unique microbiome. Science translational medicine, 6(237), 237ra65.

Abrahamsson, T. R., Jakobsson, H. E., Andersson, A. F., et al. (2014). Low gut microbiota diversity in early infancy precedes asthma at school age. Clinical and experimental allergy : journal of the British Society for Allergy and Clinical Immunology, 44(6), 842–850.

Ajslev, T. A., Andersen, C. S., Gamborg, M., et al. (2011). Childhood overweight after establishment of the gut microbiota: the role of delivery mode, pre-pregnancy weight and early administration of antibiotics. International journal of obesity (2005), 35(4), 522–529.

Dugoua, J. J., Machado, M., Zhu, X., et al. (2009). Probiotic safety in pregnancy: a systematic review and meta-analysis of randomized controlled trials of Lactobacillus, Bifidobacterium, and Saccharomyces spp. Journal of obstetrics and gynaecology Canada : JOGC = Journal d'obstetrique et gynecologie du Canada : JOGC, 31(6), 542–552.

Fallani, M., Young, D., Scott, J., et al. (2010). Intestinal microbiota of 6-week-old infants across Europe: geographic influence beyond delivery mode, breast-feeding, and antibiotics. Journal of pediatric gastroenterology and nutrition, 51(1), 77–84.

Shah, N.P. (2011). Bacteria, Beneficial: Bifidobacterium spp.: Morphology and Physiology. 10.1016/B978-0-12-374407-4.00043-1.

Stokholm, J., Thorsen, J., Chawes, B. L., et al. (2016). Cesarean section changes neonatal gut colonization. The Journal of allergy and clinical immunology, 138(3), 881–889.e2.

Yuan, C., Gaskins, A. J., Blaine, A. I., et al. (2016). Association Between Cesarean Birth and Risk of Obesity in Offspring in Childhood, Adolescence, and Early Adulthood. JAMA pediatrics, 170(11), e162385.