A heatlthy gut flora is a balance between ‘good’, beneficial bacteria and ‘bad’ bacteria. Imbalances in gut flora are believed to be contributing factors to many chronic diseases such as irritable bowel syndrome, inflammatory bowel disease, autoimmune disease as well as gas and bloating. Now it appears that gut microflora may contribute to weight gain as well.

A study published in the current edition of The American Journal of Clinical Nutrition found significant differences between the gut floras of normal weight woman compared to overweight woman. Overweight woman had higher numbers of the ‘bad’ bacteria, Bacteroides and Staphlococcus, when compared to normal weight woman. In contrast, normal weight woman were shown to have higher amounts of the ‘good’ bacteria, Bifidobacterium. Interestingly, larger weight gain during pregnancy was associated with higher amounts of Bacteroides and Staphlococcus while woman with normal weight gain during pregnancy had higher numbers of the ‘good’ Bifidobacterium bacteria.

The authors offer 3 hypotheses that could explain why gut dysbiosis appears to contribute to weight gain:

1. Pathogenic (‘bad’) gut flora may cause increased glucose absorption and enhanced fat storage contributing to increased weight gain.
2. Pathogenic gut flora leads to a catabolic state (calorie storage)
3. Pathogenic gut flora contributes to low-grade, systemic inflammation which is associated with obesity and obesity related conditions such as heart disease, diabetes and depression.

Any new clues we have to understand why some women seem to gain weight easily or have difficulty loosing weight catches my attention. However, this study did not address the obvious question of whether gut dysbiosis leads to weight gain or if being overweight leads to gut dysbiosis. Clearly more research is warranted. Nonetheless, this is a promising study and may support the recommendation of eating more probiotic-rich, fermented foods and/or supplementing with a probiotic – both during a weight loss regime and during pregnancy. Because a pregnant mother’s diet and probiotic intake contributes to their developing infants intestinal flora, it may be that supplementing with probiotics during pregnancy will contribute both to the later health of the infant and possibly even protect against childhood obesity.

Am J Clin Nutr. 2008 Oct;88(4):894-9.
PMID: 18842773 [PubMed – indexed for MEDLINE]

The contents of this blog are for informational purposes only. It is not intended as professional medical advice, diagnosis or treatment. Please see an Akasha physician or another qualified health care provider with questions regarding a medical condition or treatment.