How A Healthy Gut Can Help Us Meet Our New Year’s Weight Loss Resolutions
One of the most common New Year’s resolutions surrounds losing the few extra pounds we tend to gain from all the good eats during the holiday season. This goal tends to be addressed through dieting, exercising, and avoiding additional caloric intake. However, there is something else that can help us meet our resolutions, and that is taking time to restore the health of our digestive system.
Our digestive tract comprises over a thousand species of microorganisms that are involved in helping our bodies produce energy, synthesize vitamins, and digest the food we eat. The gut consists of five primary families of bacteria and archaea, Bacteroidetes, Firmicutes, Actinobacteria, Proteobacteria, and Verrucomicrobiai.1 Studies have shown that a diverse microbiome composition has been linked to the prevention of weight gain.2 Vice versa, obesity is linked to having a less diverse microbiome.3 A diverse microbiota has also been linked to positive outcomes in chronic diseases such as Type 2 diabetes, cardiovascular disease, and inflammatory diseases. Understanding the role of the various microorganisms in the gastrointestinal tract can help us learn how our weight is impacted by our gut health.
Gut Bacteria and Weight Loss
Bacteroidetes and Firmicutes make up almost 90% of the microbiota in the gut.1 These families of bacteria play valuable roles in the functionality of the digestive tract, and when their counts are off, we can see an impact on the body as a whole. Bacteroidetes have been linked to reducing body fat composition4, and having a more significant level in the body was linked to weight loss.5 For Firmicutes, higher levels of these organisms were related to obesity, adverse effects on energy utilization by the body, decreased satiety, and increased appetite.6 This was demonstrated in studies of obese participants who presented with higher Firmicutes and a higher ratio of Firmicutes to Bacteroidetes.3 Having an imbalance of these microorganisms is termed gut dysbiosis.1
In addition to what organisms make up the microbiota, the byproducts of these organisms can impact our ability to lose weight. An example of this is the short-chain fatty acids (SCFAs) that are produced to help maintain balance within the gut. Butyrate, acetate, and propionate are all specific examples that play roles in the balance of glucose in our body, our sensitivity to insulin, and our weight.1 These SCFAs also play a role in inflammation, which can correlate to weight gain by helping to strengthen the barrier of the intestinal system and prevent leaky gut syndrome.7
What You Can Do
With this knowledge of how our gut microbiome can impact our weight, how can we work to improve our gut health? Although we have discussed the microorganisms that naturally make up the digestive tract, what about the microorganisms that shouldn’t be there? Over time our body can get exposed to pathogenic bacteria when we get sick, and the antibiotics we take can help kill off the pathogenic bacteria while also harming the good bacteria we have. This doesn’t mean we should never have antibiotics; they are good when we need them. But we have to ensure we are helping to replenish and restore the healthy organisms in our digestive tract.
Several outlets exist to help us restore our gut health. The first is dietary interventions. One study showed that a low caloric intake diet for one year demonstrated increased counts of Bacteroidetes (which we know can be associated with prevention against increased body fat).5 Other studies showed that in obese individuals with higher Firmicutes to Bacteroidetes ratios, higher intake of fiber (between 14 and 20 grams daily from legumes and fruit) and whole grains resulted in more significant health outcomes and weight loss.1, 3, 8-9
In addition to dietary interventions, adding a probiotic can potentially provide some benefits concerning weight loss. One study took 20 participants and gave them a high-fat content diet for 4 weeks. In the participants who took probiotics, there were fewer gains in weight and body fat noted than in those who did not have probiotics.10 Another study demonstrated significant positive changes in BMI, weight, and waist circumference in adults taking probiotics compared to those who did not.11 Live probiotics that contain strains of Lactobacillus gasseri and Bifidobacteria longum are known to have positive effects on the colonic microbiota and can help improve overall health in individuals who use probiotics.1, 12-13
Other examples of interventions that have been more challenging to link to weight loss because of improved gut health include prebiotics and exercise. Some studies present some evidence that these may be beneficial, but due to study design cannot be conclusive of the gut health outcomes on weight loss.6, 14-16
Overall, our gut health is important. A diverse and appropriate microbiota composition can be linked to weight loss, prevention of body fat mass gains, and decreased gut inflammation. Utilizing dietary changes and probiotics can also benefit our digestive health while helping us meet the weight loss-related New Year’s resolutions we have set for 2023. If you feel that your gut health could be playing a role in your weight, we’d love for you to schedule a free 15 minute consultation with a pharmacist in your state.
Post Written By: Kathryn Schwaller, PharmD Candidate 2023 Cedarville University School of Pharmacy
Edited by Lindsey Dalton, PharmD
- Aoun A, Darwish F, Hamod N. The Influence of the Gut Microbiome on Obesity in Adults and the Role of Probiotics, Prebiotics, and Synbiotics for Weight Loss. Prev Nutr Food Sci. 2020;25(2):113-123.
- Menni C, Jackson MA, Pallister T, et al. Gut microbiome diversity and high-fiber intake are related to lower long-term weight gain. Int J Obes. 2017. 41:1099-1105
- Kasai C, Sugimoto K, Moritani I, et al.Comparison of the gut microbiota composition between obese and non-obese individuals in a Japanese population, as analyzed by terminal restriction fragment length polymorphism and next-generation sequencing. BMC Gastroenterol. 2015.15:100.
- Liu R, Hong J, Xu X, et al. Gut microbiome and serum metabolome alterations in obesity and after weight loss intervention. Nat Med. 2017. 23:859-868
- Ley RE. Obesity and the human microbiome. Curr Opin Gastroenterol. 2010. 26:5-11.
- Gomes AC, Hoffmann C, Mota JF. The human gut microbiota: metabolism and perspective in obesity. Gut Microbes. 2018. 9:308-325.
- Chambers ES, Preston T, Frost G, Morrison DJ. Role of gut microbiota-generated short-chain fatty acids in metabolic and cardiovascular health. Curr Nutr Rep. 2018. 7:198-206.
- Hjorth MF, Roager HM, Larsen TM, et al. Pre-treatment microbial Prevotella-to-Bacteroides ratio,determines body fat loss success during a 6-month randomized controlled diet intervention. Int J Obes. 2018. 42:580-583
- Simpson HL, Campbell BJ. Review article: dietary fibre-microbiota interactions. Aliment Pharmacol Ther. 2015. 42:158-179.
- Osterberg KL, Boutagy NE, McMillan RP, et al. Probiotic supplementation attenuates increases in body mass and fat mass during high-fat diet in healthy young adults. Obesity. 2015. 23:2364-2370.
- Wang ZB, Xin SS, Ding LN, et al. The potential role of probiotics in controlling overweight/obesity and associated metabolic parameters in adults: a systematic review and meta-analysis. Evid Based Complementary Altern Med. 2019. 2019:3862971.
- Qian L, Gao R, Huang J, Qin H. Supplementation of triple viable probiotics combined with dietary intervention is associated with gut microbial improvement in humans on a high-fat diet. Exp Ther Med. 2019. 18:2262-2270
- Okeke F, Roland BC, Mullin GE. The role of the gut microbiome in the pathogenesis and treatment of obesity. Glob Adv Health Med. 2014. 3:44-57
- Brooks L, Viardot A, Tsakmaki A, et al. Fermentable carbohydrate stimulates FFAR2-dependent colonic PYY cell expansion to increase satiety. Mol Metab.2016. 6:48-60.
- Allen JM, Mailing LJ, Niemiro GM, et al. Exercise alters gut microbiota composition and function in lean and obese humans. Med Sci Sports Exerc. 2018. 50:747-757.
- Whisner CM, Maldonado J, Dente B, et al. Diet, physical activity and screen time but not body mass index are associated with the gut microbiome of a diverse cohort of college students living in university housing: a crosssectional study. BMC Microbiol. 2018. 18:210.