BACTEROIDES: A Species of gut bacteria LINKED TO enhanced cognition and language skills in infant boys

From https://doi.org/10.1080/19490976.2021.1930875, Published online16 Jun 2021

This study found that boys with Bacteroides germs in their bowel had enhanced brain development. This University of Alberta-led research followed more than 400 infants from the “CHILD” Cohort Study in Edmonton.

Boys with a gut bacterial composition high in the Bacteroidetes germs at one year of age were found to have more advanced cognition and language skills one year later. The finding was specific to male children.

Dr. Anita Kozyrskyj, professor of pediatrics at the U of A and principal investigator of the SyMBIOTA (Synergy in Microbiota) laboratory, with associate professor Piush Mandhane and their research team, studied bacteria from the infants and identified three groups exhibiting similar dominant bacterial clusters. They then evaluated the infants and found that only male infants with Bacteroidetes-dominant bacteria showed enhanced neurodevelopment.  “We know that Female children score higher (at early ages), especially in cognition and language,” said Dr. Kozyrskyj,  “but when it comes to gut microbial composition, it was the male infants where we saw this obvious connection between the Bacteroidetes and the improved scores. The differences between male and female gut microbiota are very subtle, but girls are more likely to have more Bacteroidetes. So perhaps most girls have a sufficient number of Bacteroidetes and that’s why they have improved scores over boys”.

The research replicates similar findings from a U.S. study.

According to Dr. Kozyrskyj, Bacteroidetes produce metabolites called sphingolipids, which we need for brain growth. “It makes sense that if you have more of these microbes and they produce more sphingolipids, then you should see some improvement in terms of the formation of neuron connections in our brain and improved scores in cognition and language,” she said.

According to Dr. Kozyrskyj, caesarean birth can significantly deplete Bacteroidetes. Also, the infant’s gut microbiota Factors improve if they are breasted, have a high-fibre diet, live with a dog and are exposed to nature and green spaces.

While the findings don’t necessarily mean that children with a lower proportion of Bacteroidetes will remain behind their peers in later childhood or adulthood, the researchers believe that the study offers a way to potentially identify children at risk of neurodevelopmental disorders.



If you must have every last detail about Bacteroides, see/visit a paper entitled “Bacteroides: the good, the bad and the nitty-gritty”, by Hannah M Wexler. This is a well-written, amazingly detailed treatise on Bacteroides which will give you answers to your every question on the subject.

You can access the phenomenal Ms. Hannah Wexler’s paper on Bacteroides in: Clin Microbiol Rev, 2007 Oct:20 (4): Pages 593-621. doi: 10.1128/CMR.00008-07,  At ………………  https://pubmed.ncbi.nlm.nih.gov/17934076/

I am a Toronto-trained Urologist. I practiced in downtown Toronto, from 1977 to 1997, when I went to Saudi Arabia as chief of Urology at the Armed Forces (teaching) hospital in Tabuk. Returning to Toronto in Y2000, I switched to family practice. In 2007, began to prescribe Hormone Restoration Therapy and in 2012, I became a member of the American Academy of Antiaging Medicine [A4M]. I successfully wrote the A4M's written examination in December, 2013 and In May, 2016 I passed the oral examination, for accreditation as a BHRT consultant. In 2014 I began BHRT practice in Collingwood, Ontario and in January, 2017, joined the Stone Tree Naturopathic Clinic. Now I am 82 and have retired, but it seems wasteful to jettison my learning and experience: the medical establishment knows nothing of BHRT / Functonal medicine and I feel obliged to offer my knowledge in the interest of those who are willing to think outside the box. MY QUALIFICATIONS: MB, BS, (from UWI), 1964. LMCC 1969. FRCSC (Urology), 1974. ECFMG 1984. Florida license 1998 [inactive], ABAARM Certification [A4M], 2016. I am a Member of CSAMM [the Canadian Society for Aging and Metabolic Medicine], the OMA&CMA, SUSO, CUA, RCP&S/C. PRACTICE TO DATE: Consultation in Functional Medicine, including assessment of Chronic Fatigue Syndrome, Fibromyalgia, Andropause, Menopause, Teenage and Postpartum Depression/Panic Attacks, Thyroid Hormone malfunction, Infertility, Sexual Dysfunction and “the Undiagnosable”. ALL ARE WELCOME to read, comment or question!

Leave a Reply