Written by Azadeh Khiabani, Ph.D. in Food Biotechnology
The human body contains trillions of bacteria, with the majority residing in the gut. The gut microbiome plays crucial roles in maintaining overall health, such as communicating with the body’s immune system and producing essential vitamins. Additionally, these bacteria can influence digestion, produce chemicals that induce feelings of fullness, and ultimately impact body weight.
This article aims to explain how the gut microbiome influences body weight and the necessary nutrients for cultivating healthy gut bacteria.
The effect of gut microbiome on food digestion
The gut microbiome plays a crucial role in food digestion as it covers the surface of intestinal cells, directly interacting with the food we consume. This interaction can impact nutrient absorption and energy storage in the body. A study comparing the gut microbiome of twins found that those who were obese had less diverse and numerous gut microbiomes compared to their normal-weight siblings. This difference may be attributed to the influence of bacteria on the digestion of various foods. For instance, while humans cannot digest fiber, certain gut bacteria can break down fiber and produce chemicals that support gut health and potentially aid in weight loss.
The composition of bacteria in the gut may also determine how much weight individuals can lose on a specific diet. Additionally, the gut microbiome has the ability to metabolize antioxidants found in plants, known as flavonoids, which could help prevent weight gain. Moreover, gut bacteria can impact the absorption of dietary fat in the gut, influencing how fats are stored in the body.
The effect of gut microbiome on inflammation
Inflammation occurs when the body’s immune system is activated to fight infection. Unhealthy diets high in fat, sugar, or calories can also trigger inflammation, leading to an increase in inflammatory chemicals in the bloodstream and adipose tissue, potentially causing weight gain.
The gut microbiome plays an important role in inflammation. Certain bacterial species produce chemicals like lipopolysaccharides, which, when they enter the bloodstream, can cause inflammation, weight gain, and insulin resistance. Conversely, beneficial species of gut bacteria may help reduce inflammation and prevent weight gain. For instance, bifidobacteria can maintain a healthy gut barrier preventing inflammatory chemicals from entering the bloodstream.
Research in this area is still relatively new, and the full extent of how the gut microbiome influences inflammation and weight changes in humans is not yet fully understood.
The effect of gut microbiome on satiety or hunger
The human body produces a variety of hormones, such as leptin and ghrelin, that play a crucial role in regulating appetite. Some studies suggest that the gut microbiome can influence the production of these hormones and impact feelings of hunger and satiety. Short-chain fatty acids, which are produced by specific gut bacteria that break down fiber, can also have an effect. For example, propionate is a chemical that increases feelings of satiety and can aid in weight reduction. Additionally, research has indicated that prebiotic supplements, containing compounds that are fermented by gut bacteria, may have a similar impact on appetite.
Foods beneficial for the gut microbiome
Whole grains (Functional foods)
Fruits and vegetables (Essential nutrients and why the body needs them)
Nuts and seeds (Functional foods)
Polyphenol-rich foods (Functional foods)
Fermented foods (Fermented foods)
Probiotics (Probiotics)
Prebiotics (Prebiotics)
Foods that may harm the gut microbiome
Sweet foods
Artificial sweeteners
Foods containing unhealthy fats
For more information, please refer to the articles on (Microbiome), (Synbiotics), and (Postbiotics).
