As consumers become more conscious of the connection between the foods and beverages they consume and their health and well-being, the human gut is increasingly finding itself in the spotlight. Why? There are more than 100 trillion microorganisms, including bacteria, parasites, viruses, and fungi, in the human gut. This vast ecosystem, known as the gut microbiome, is primarily composed of bacteria and contains the largest concentration of microbes in the human body.
One might think the gut microbiome’s only job is to aid in the digestion of food, but research indicates it does much more than that. A person’s immune health, metabolism, weight, sleep, and energy levels are all influenced in part by the gut microbiome. Some emerging research suggests diet and its tie to the microbiome could help manage conditions such as Crohn's disease, ulcerative colitis, and irritable bowel syndrome. These critical functions and possible outcomes signal the importance of maintaining gut health.
What constitutes a healthy gut?
A healthy gut microbiome relies on the richness and diversity of the bacteria present. Having a wider array of microbes in the gut creates a healthier and more resilient environment, whereas symptoms of an unhealthy gut tend to present themselves when a lack of diversity and balance exists. Research shows that while genetics are a factor, diet has emerged as having substantially more of an impact on the inner workings of your gut, so what you eat truly matters.
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Most nutrients, including fats, carbohydrates, and proteins, are absorbed in the small intestine. However, nutrients that are partially digested or undigested, such as resistant starches, fiber, and some protein, can make their way to the colon. Most of the microbiome resides in the colon, so nutrients that reach the colon become a food source for the bacteria. Nondigestible carbohydrates and some undigested protein are fermented in the colon, yielding gases such as methane and carbon dioxide, and short-chain fatty acids.
What’s so special about short-chain fatty acids?
Short-chain fatty acids, which include acetate, propionate, and butyrate, are the primary products of gut bacteria during the breakdown of non-digestible carbohydrates. Collectively, they are shown to influence energy levels, fat accumulation, and appetite, and as such, may regulate a person’s metabolism. They also play an important role in maintaining a healthy intestinal lining, which in turn reduces leaky gut and could prevent systemic inflammation. They have also been associated with a decreased risk of some autoimmune diseases, including inflammatory bowel disease, inflammatory arthritis, and multiple sclerosis. We can increase the production of these healthy-promoting compounds by increasing our consumption of fiber.
Harmony is key
Diversity and balance among the bacteria in the gut is imperative to experience the benefits associated with gut health. When the symbiotic relationship is off-kilter, unhealthy bacteria can take over leading to dysbiosis, producing metabolites that pass through the lining of the gut and into the bloodstream, spreading inflammation to other parts of the body.
So, how do you maintain that balance?
Foods containing prebiotics and probiotics are important to maintain a healthy digestive system. High-fiber foods like whole grains, legumes, fruits, and vegetables, and many shelf-stable foods such as cereals, are sources of prebiotic fiber. Fermented products such as yogurt, kefir, and kombucha contain probiotics, which are live bacteria and yeasts that support the body in building and maintaining a healthy colony of bacteria and other microorganisms in the gut. Making a conscious effort to incorporate foods that help maintain bacterial diversity and create a harmonious state in the gut could help people reap the promises of a healthy gut.
Gut health innovation on the rise
Research is constantly being conducted to better understand the impact digestive health products have, not only on the microbiome, but also general health and disease prevention. Simultaneously, research and development efforts are continuing to look for new and better ways to deliver these wellness solutions to consumers. As new research surfaces, food scientists are rising to the occasion, delivering gut-friendly innovations across all product categories.
Paving the way to personalized nutrition
Scientist's dreams of personalized nutrition have been slow to materialize since the first sequencing of the human genome nearly 20 years ago. We now understand that understanding the microbiome, with its estimated 2 million genes vs 23,000 human genes, is key to success.
It is estimated that an individual has anywhere from 500 to 1,000 different species of bacteria in their gut, and no two microbiomes are the same. Despite the uniqueness in composition, studies have suggested people can be grouped into two or three different classifications based on the presence of certain bacteria. As more research emerges, scientists will be looking to fill in the gaps between these classifications, create more focused classifications based on functional profiles, and construct a spectrum of microbial states that people fit into. Continued exploration of the interdependencies between diet, microbiome, and health presents exciting possibilities for new food product development, distribution, and packaging, as well as to improve dietary planning and human health through personalization in the future.
The gut microbiome's impact on health and the risk of disease is a constantly evolving area of study. Explore the following research studies in IFT's peer-reviewed journals to deepen your knowledge.
John Ruff, CFS, is the chief science advisor at IFT and an IFT Past President.