In its composition, metabolic and functional profile, the gastrointestinal microbiome is not only complex, but also challenging to master. There have been many attempts to modify the composition of the microbiome over the years, most of which included delivering microorganisms that were perceived as beneficial. Previous attempts to adjust the profile of the gut microbiome have been made by modifying diets or by including probiotics into the diet by way of food or dietary supplements.
The gut microbiome is usually stable and overall composition is not easily altered through administration of traditional probiotics from genera such as Lactobacillus and Bifidobacterium, although some probiotic strains may transiently colonise the human gastrointestinal tract. The discovery of non-traditional or commensal microorganisms isolated from the microbiome can offer opportunities to deliver probiotics which are associated with new health benefits. However, commercialisation of such microorganisms as probiotics is associated with many challenges. The industrialisation of unconventional probiotic strains from genera that are more fastidious is particularly likely to be a challenge. Introduction of unconventional genera that are not currently associated with fermented foods is also expected to raise questions around safety and it is anticipated extensive work will be needed for the safe introduction of these strains into food and dietary supplements.
Modification of diets is another strategy that may be used to induce short-term changes in the composition of the microbiome. Studies have shown when individuals change from an animal-based diet to a plant-based diet, significant changes can be seen in the composition of the gut microbiome, after only a few days of deviation. Also, specific carbohydrates that are resistant to digestion in the small intestine, such as FOS, polydextrose and resistant starches have been used to boost populations of Bifidobacteria and other species which can utilise the carbohydrates in the colon. It is anticipated that a variety of other specific carbohydrates, both oligosaccharides and resistant polysaccharides will be important tools to add diversity and maintain beneficial strains in the gut microbiome. Human milk oligosaccharides are one such type of carbohydrate, where potential to change the composition of the infant gut microbiome is well documented. It is predicted that the use of such oligosaccharides in infant formula will help build the most appropriate microbiome for infants, setting the foundation for the best possible start in life. Hence, the use of specific prebiotics is expected be an important tool in the development of a healthy microbiome.
It is anticipated that the number of ingredients available for adjusting the composition of the microbiome will expand in the near future, and that these functional foods will act as valuable tools in promoting a healthy microbiome. Utilising the new commensal strains and prebiotic ingredients gives new opportunities to reduce the prevalence of autoimmune diseases and stem the increasing prevalence of a range of non-communicable diseases such as diabetes and cardiovascular disease.
The discoveries of how to maintain a healthy microbiome are expected to give vast commercial opportunities to incorporate solutions into food and beverages, dietary supplements and even pharmaceuticals.