Obesity’s impact on gut health

What is the Gut Microbiome?

Your gut microbiome is the environment in your intestines made up of trillions of microscopic organisms, including a diverse population of bacteria, in addition to viruses, parasites and fungi. The gut microbiome is known for the important role it plays in maintaining a healthy digestive system, however, it is also a key component to many of our body systems. Our immune, nervous, and endocrine systems all rely on a healthy gut microbiome for optimal homeostasis of the human body. In a healthy individual, these microorganisms all live symbiotically throughout the gastrointestinal tract, with the largest concentration present in the large intestines. The gut microbiome is unique to each individual and colonization begins at birth. As humans grow and develop the diversity and composition of the gut microbiota changes based on external and internal factors. 

Obesity Statistics

Obesity in the US population has been on an upward trend for the last 50 years, and studies suggest this curve will continue in the coming decades. According to the World Health Organization, obesity is defined by two factors: a body mass index (BMI) over 30 and “abnormal or excessive fat accumulation that presents a risk to health”. Current estimates from 2022 data put the prevalence of obesity in the US at 35% for adults and 19.7% for children and adolescents.

A brief look at the research

Recent studies have looked to compare the gut microbiota, the bacteria living within the microbiome, of lean versus obese subjects. While the gut microbiome of one individual can differ significantly from the next person, the findings of such studies suggest there may be additional variances between the microbiome of lean and obese subjects.  In animal models, researchers saw a difference displayed between the processing of nutrients and energy extraction between the two groups. While there is still much research to be done, there may eventually be a method for addressing obesity through the microbiome.

Optimizing Your Gut Health

In the meantime, one way to balance your gut health is through the obvious method – the foods you eat! Foods with probiotics help to introduce good bacteria to the gut microbiome and are best when incorporated daily. In addition to probiotics, many fiber-rich foods act as prebiotics functioning to provide food for our good gut bacteria. 

• Foods rich in probiotics 
  • Certain dairy products such as yogurt, kefir, sour cream and buttermilk
  • kombucha 
  • fermented vegetables (pickles, kimchi, beets, carrots and sauerkraut)
  • fermented soy produces (natto, miso, tamari sauce and tempeh)
• Fiber-rich prebiotic foods
  • Asparagus
  • Avocado
  • Banana
  • Eggplant
  • Endive and raddichio
  • Garlic, leeks and onions
  • Honey
  • Jerusalem artichokes
  • Jicama
  • Kefir
  • Legumes (such as lentils, beans, chickpeas, peanuts, alfalfa)
  • Whole grains (such as oats, farro, barley, wheat, rye)
  • Yogurt

Conversely, research has also indicated that diets rich in processed foods, high in fat and added sugar, can potentially change the environment for healthy microbes. Without adequate fiber in the diet to feed a healthy microbiome the proportion of good bacteria may be altered leading to pH changes in the colon and allowing bad bacteria to colonize. This can result in changes to digestion and absorption of some nutrients. 

Obesity related to gut health is an important and ongoing area of research. One thing that can be addressed today is focusing on a whole food, fiber-rich diet to promote a happy gut. The registered dietitian-nutritionists with ADH are well versed in working with each individual to promote healthful food choices and help identify ways to enhance your diet.