Does Gut Flora Effect Weight Management?

By: Deedra Mason, ND  nutraMetrix® | Director of Clinical Education & Research

Many of us have been under the impression that our gut and its flora are out of balance due to excessive weight.  That has been the popular idea for quite some time, but we are finding out that it may be the other way around! New connections between the health and balance of gut flora are changing the way we look at and interpret the ways these two are connected.

Healthy Gut flora can be enough to help you “whittle that waist”.  These studies are not quite sure which particular species of flora are important, but certain things have been made clear.  We now know that slender people and obese individuals have different gut flora.  Due to poor diets, gut flora can be thrown off balance.  In a study assisted by Cornell College called the British Gut Project, a participant was asked to eat a fast-food based diet for ten days to find out that he lost nearly 40% of his microbiome diversity.  This lack of diversity is a universal sign of poor health.

Thankfully, the literature supports the use of probiotics to help protect your gut flora which assists you in maintaining a healthy weight.

Researchers reported that “even though diet will affect gut flora composition, most studies conclude that gut flora on it’s own has an effect on weight. Alteration of the gut microbiota can be an important part of a weight loss program.”

Pro-biotics may assist the gut in gaining energy from polysaccharides, help the body in it’s sensitivity to insulin and how the body handles inflammation and energy use.   Several mechanisms have been proposed as to how gut flora regulates weight. Inflammation, energy from polysaccharides, insulin sensitivity and energy expenditure and storage are all affected by gut flora.

Probably the most important takeaway was learning that many will argue that a healthy diet will improve over all well-being, but many do not understand the impact of the simple balance of flora.  Having a poor gut flora balance may lead to sugar cravings, food cravings and therefore play a major role in influencing our food choices.

Other studies support the findings of those from the national academy of sciences, when researches at Harvard found in another study, Children that were born via C-section had a two times more likely chance of being overweight because they did not have the benefits or the exposure to the flora through the birth canal.




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Obesity Alters Gut Microbial Ecology.

Vael C, Verhulst SL, Nelen V, et al.

Intestinal Microflora and Body Mass Index During the First Three Years of Life: An Observational Study.

Gut Pathog. 2011 May 23;3(1):8.

Kalliomaki M., Collado M.C, Salminen S., et al.

Early Differences in Fecal Microbiota Composition in Children May Predict Overweight