How Your Gut Bacteria Can Influence Your Weight Loss | Improve Metabolism
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Misbah Wasi

Functional Nutrition Specialist, Scientific & Regulatory Advisor for Health Supplements

Misbah Wasi is a seasoned professional in the field of Nutrition Science and Food Regulation for over 15 years. Currently, she is lendin her expertise in the area of Health Supplements and Nutraceuticals and is an active member of the Standards Review Group (SRG) - Nutraceuticals FSSAI Ms. Wasi is a post-graduate in Food and Nutrition. Certified Lead Food Safety Management Systems Auditor (FSMS, FSSC 22000) and a certified FoSTaC traine for Health Supplements and Nutraceuticals. She is also a Subject Matter Expert for ‘Food Regulations in India’ for IFLR (International Food Laws and Regulations) course at Michigan State University.

How Your Gut Bacteria Can Influence Your Weight Loss

The gut microbiome is often referred to as our “second brain.” The human gastrointestinal tract is colonized by large numbers of microorganisms, including bacteria, viruses, fungi, and protozoa, collectively known as the gut microbiota. The gut microbiome consists of trillions of microbes that live in the digestive tract. In fact, our bodies have many more gut bacteria than our human cells. Each person’s gut microbiome is unique, like a microbial fingerprint, and is shaped by genetics and our environment. The diversity and composition of the gut microbiome are influenced by multiple factors, such as dietary habits, the use of antibiotics and medications, aging, and other environmental factors. So, these diverse gut bacteria directly affect the brain and brain signals, influencing stimulants for hunger and appetite.

These gut bacteria have various other health benefits:

  • Builds a strong immune system



  • Strengthens intestinal lining


  • Harvests Energy


  • Produces appetite-controlling hormones


  • Synthesizes vitamins and essential nutrients, including short-chain fatty acids (SCFAs). 


Any disturbance in the gut bacteria can lead to dysbiosis or symbiosis. “Dysbiosis” refers to an unhealthy balance of gut microbes and often signals that there is a decrease in microbial diversity and a shift in the balance between “healthy” and “unhealthy” microbes. Whereas, in symbiotics relationship, there is a healthy balance between commensal and pathogenic microorganisms. Therefore, it is crucial to maintain a balance between good bacteria and bad bacteria.


Gut Bacteria and Weight Loss


The prevalence of several chronic diseases is growing worldwide. However, obesity is the primary culprit for chronic diseases and has been a major concern for decades. Although several methods for weight loss are used, obesity remains a major public health problem, which requires effective nutritional and medical solutions. A high-calorie diet is a main factor for obesity and may induce changes in the function of the gut microbiome. There’s growing evidence that people who carry excess weight tend to have a different composition of gut microbes compared with lean individuals. According to a journal, the gut microbiota of obese people may be less diverse and contain less beneficial bacterial strains. Balancing the gut microbiota in the intestine might prove to be a great influence on the weight loss journey. Here are some ways in which gut bacteria can influence weight loss:


   1. Regulating metabolism


Gut bacteria are well known for their metabolic functions. Gut bacteria have the ability to salvage unabsorbed dietary sugars, such as lactose and alcohol, and convert them into short-chain fatty acids (SCFAs) that are then used as an energy source by the intestine. SCFAs promote the growth of intestinal epithelial cells and control their proliferation and differentiation. This can affect how much energy we extract from the food we eat, which in turn can affect our weight. SCFAs also play a role in regulating the immune system and inflammatory response.


   2. Synthesis of Essential Vitamins


The GI microbiota is crucial to the synthesis of essential vitamins which the host is incapable of producing. Lactic acid bacteria are key organisms in the production of vitamin B12, which cannot be synthesized by animals, plants, or fungi. Bifidobacteria are the main producers of folate, a vitamin involved in vital host metabolic processes, including DNA synthesis and repair. Further vitamins, which gut microbiota have been shown to synthesise in humans, include vitamin K, riboflavin, biotin, nicotinic acid, pantothenic acid, pyridoxine, and thiamine. Gut bacteria can also metabolise bile acids that are not reabsorbed for transformation to secondary bile acids.


   3. Influencing inflammation


Weight gain can also take place due to inflammation in the body, which can be caused due to various reasons. A diet high in sugar, fat, and calories can induce inflammation. Generally, inflammation takes place as a defence system against any infection to protect your immunity. Inflammation is also caused by chemicals like lipopolysaccharide (LPS). So, when certain gut bacteria produce LPS, it can cause inflammation which may contribute to weight gain and insulin resistance. But beneficial gut bacteria prevent inflammatory chemicals from passing from the blood and hence prevent weight gain. A high intake of prebiotics enhances the activity of good gut bacteria.


   4. Modulating hormones & Controlling appetite


A variety of hormones are produced by the body, which affects the appetite, such as leptin, ghrelin, and peptide YY. These are the hormones that help you feel hungry or full. Gut bacteria express carbohydrate-active enzymes, which endow them with the ability to ferment complex carbohydrates generating metabolites such as SCFAs. SCFAs have also been shown to modulate appetite regulation and energy intake via receptor-mediated mechanisms. Propionate has beneficial effects in reducing food intake and reducing weight gain. According to a study, it was found that regular intake of propionate for six months significantly increased levels of the hormones peptide YY and GLP-1, which influence hunger.

How do we improve Gut Bacteria?


You can improve your gut health by making changes in your diet and lifestyle. Like, physical activity may change the composition of our gut bacteria. It can promote the growth of beneficial strains while decreasing obesity-related bacteria. The following ways may help to improve gut health:

  • Avoid Antibiotics: Antibiotics, whether prescribed or in the food chain, have the potential to profoundly impact the microbiota. Excess/unnecessary intake of antibiotics causes dysbiosis in the intestine. This leads to various diseases.


  • Increase intake of fermented foods: Fermented foods are loaded with good bacteria, i.e., probiotics. A high intake of probiotics modifies the gut microbiota.


  • Increase fibre intake: Fibre (prebiotics) is the food for healthy gut bacteria. This leads to the production of SCFAs which help in controlling weight.


  • Increase physical activity: Physical activity improves the composition and diversity of gut bacteria. Exercise is also recommended to lose weight and reduce stiffness.


  • Reduce stress/tension: Excessive stress can disturb the gut microbiota and can lead to severe IBS. It is important to grateful and thankful for whatever you have in life.
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