Trends analysts tell us that gut health was one of the top seven areas of growth in the wellness space of 2024.[1] The bacteria which makes up the microbiome is making news too. Staggering growth has been seen in microbiome-related research over the last 20 years.
Figure 1. Trends in the number of microbiome publications per year indexed in Pubmed.gov.[2]
To bring this into perspective, the list below is a diverse selection of 2024 microbiome-related study titles. There’s everything from how these bacteria influence Alzheimer’s disease, to how they can help humans adapt to spaceflight…
Then there is the marketing and social media aspect. Tik-Tok announces the ‘newest sensation in gut health’ every day. Beyond probiotics, fibre, fermented foods and kombucha, are also trending.
And in case you haven’t heard, the health benefits being claimed are amazing: enhancing weight loss, improving mood, supporting the immune system and mitigating menopause are just some of the many supposed claims.
So, let’s find out what we know about the microbiome.
Could swallowing live bacteria actually be good for us?
The human gut microbiome
The human gut harbours a complex and dynamic population of approximately 100 trillion microorganisms, made up of at least 500 different species.[3][4][5][6][7] The relationship between us and our intestinal microbes is mutually beneficial – we provide a homely environment with lots to eat, while they play a crucial role in maintaining homeostasis, a form of healthy system regulation.[8] Our gut bacteria also protect us against pathogens, commonly known as bad bacteria.[9][10] If not brought into line, these microbial rascals can promote a situation called dysbiosis, a state of altered composition and function of the gut microbiome.[11] Dysbiosis can cause general digestive issues such as diarrhoea and constipation, as well as more profound gut disorders such as small intestinal bacterial overgrowth (SIBO)[12] and inflammatory bowel disease.[13] There are even potential links to obesity and type 2 diabetes,[14] as well as anxiety and depression.[15]
Probiotics
Does science back the claims popularly associated with probiotics? Delivered in a variety of forms, probiotics are administered to humans and animals alike. Typically, they don’t hang around for very long, with 2 weeks being the average.[16] This lack of longevity, however, does not render them useless! As they work their way through the gastrointestinal tract, probiotics and their metabolites interact with a variety of cells and organs and can indeed produce significant effects on human physiology.
The below points relate to scientifically confirmed probiotic actions in humans.
Table 1. Important actions related to or dependent upon probiotics, confirmed by multiple scientific studies:
| PROBIOTIC ACTIONS |
| Normalization of disturbed bacterial communities, bringing balance to the microbiome[17][18][19] |
| Competitive exclusion of and directly controlling pathogens[20][21][22][23] |
| Inactivation of toxins and carcinogens[24][25] |
| Production of short-chain fatty acids which in turn have both gut-based and systemic effects[26][27][28][29] |
| Modulating insulin sensitivity, impacting metabolism, obesity risk and cardiovascular health[30][31][32] |
| Support of epithelial cell adhesion and healthy mucous production[33][34][35][36] |
| Modulating immune function and promoting anti-inflammatory signals[37][38][39] |
| Interaction with the brain via the gut-brain axis, affecting behaviour and mood[40][41][42][43][44] |
The gut revolution
With the above in mind, its little wonder that gut health and probiotics are becoming increasingly popular. If you’ve recently discovered gut health, welcome! If you’re not here yet, come join the community and embrace probiotics, the friends within us all… Your gut will thank you for doing so!
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[18] Geirnaert A, Calatayud M, Grootaert C, Laukens D, Devriese S, Smagghe G, De Vos M, Boon N, Van de Wiele T. Butyrate-producing bacteria supplemented in vitro to Crohn’s disease patient microbiota increased butyrate production and enhanced intestinal epithelial barrier integrity. Scientific reports. 2017 Sep 13;7(1):11450.
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