The Gut Connection to Weight

June 26, 2019
Home 9 Obesity Conditions 9 The Gut Connection to Weight

The etiology of obesity is complex. The research has shown that there are many internal and external influences on body weight, one major influence being the bacteria that live within our gut, or our microbiota. As research continues to emerge on the gut-brain axis and how the microbiota that live within us have profound effects on our daily lives, let’s take a moment to explore gut health and how it affects weight loss.

The human body has more bacteria cells than human cells. Research indicates that for a 150lb male, there are approximately 40 trillion bacterial cells to the 30 trillion human cells. The majority of bacteria live in the gut and help to carry out essential life tasks like fighting infections, producing essential vitamins like Vitamin K and even regulating digestion. Gut microbiota also influences on how our bodies digest certain foods which affects how bodies regulate hormone production, especially hormones relating to satiety.

Effect on Digestion

All gut microbiota come into contact with the food we ingest which in turn how nutrients metabolized and stored. One particular study analyzed twins (over 70 sets), one of whom was obese and the other not. There was an inverse relationship between gut diversity and weight, signaling that the more gut diversity one has, the slimmer their waistline. In another study, gut bacteria from obese humans were placed into mice who then in turn gained weight, suggesting a causation to weight gain.

Gut bacteria can also influence how we digest certain nutrients like dietary fats and antioxidants, all of which has an effect on our body weight. One example would be a plant compound known as flavonoids which has been linked to preventing weight gain. 

Lastly, we know that humans cannot digest fiber without the aid of the gut microbiota. In fact, the byproducts of fiber digestion have been linked to the reasons why people who consume higher fiber diets have lower rates of overweight and obesity.

Effects on Satiety

Our bodies produce chemicals and hormones such as peptide YY (PYY), ghrelin, glucagon-like peptide 1 (GLP-1) and leptin, all of which regulate appetite. Each species of bacteria that live in our gut affects the quantities of each hormone produced which can make someone feel more or less hungry. Different gut microbiota that helps to digest dietary fibers encourage the production of proprionate, a short-chain fatty acid that’s been linked to increased circulating levels of hunger-influencing hormones.

Of interest to note, in one particular study where overweight people took supplemental proprionate, they experienced a reduced overall intake of food and reduced weight gain as well as circulating satiety hormones GLP-1 and PYY. This increase in proprionate links back to the intake of prebiotic fibers. In fact, R-Kane Nutritionals’ TinyMeal line is specifically formulated with 10g of prebiotic fiber that directly s support not only appetite but also calcium absorption and improved gut health.

Effects on Inflammation

By definition, inflammation is the body’s response to injury – it’s the body’s way to signal to the immune system that help is needed. Inflammation has been directly linked to diets that have an excess of fat, sugar and calories that contribute to weight gain. Some gut microbiota species produce lipopolysaccharides which is known to cause inflammation when it enters into the blood. Upon further study of gut microbiota and inflammation, studies have found that there exists an inverse relationship between levels of circulating c-reactive protein (a blood marker of inflammation) and lower gut diversity. In other words, the lower the gut diversity the higher the c-reactive protein, the more inflammation and weight gain.

In contrast, some gut species can actually promote reduction in inflammation and prevention of weight gain. Two such species Akkermansia and Bifidobacteria actually prevent inflammatory chemicals from entering into the bloodstream. In several animal models mice that have higher populations of Akkermansia actually had reduced body weight and insulin resistance. In similar studies, mice fed diets rich in prebiotic fibers helped to increase the presence of Bifidobacteria, which helped to blunt weight gain and insulin resistance with no effect on total energy intake.

While this is a new area of research and more research needs to be done to fully understand the gut-brain axis and its effect on obesity, there is no doubt that a connection exists. From antiquated phrases like, “you are what you eat,” to Hippocrates bolding proclaiming, “Let food be thy medicine,” there is absolute truth in the fact that a well-balanced diet will promote a body that is overall healthy. When we take care of our bodies from the inside out, eating nutrient and fiber rich foods like R-Kane Nutritionals’ TinyMeal bars, we see real, long-term changes in our body weight.


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