Feature
Tweaking gut microbes for better health is still a work in progress
The approach promises benefits across several diseases but still hasn ’ t reached the clinic in a meaningful way
“ The probiotic industry , which makes billions of dollars every year , has sort of brainwashed the public into taking probiotics because they promote health , but it has little evidence to support it .”
It ’ s a widespread notion that the good microbes in our gut play an important role in health and disease . All you have to do is look at the popularity of probiotics , the so-called good bacteria packed in foods and supplements that are believed to make people healthier . These have become so sought-after that they ’ re now marketed in beauty products , the New York Times reported a few years back .
But the science of optimally balancing the many millions of different microbes living in the intestine , collectively called microbiome , is still shaky , a fact that should give pause to anyone splashing out on probiotics in the hopes of keeping diseases away .
“ The probiotic industry , which makes billions of dollars every year , has sort of brainwashed the public into taking probiotics because they promote health , but it has little evidence to support it ,” Dr Eugene Chang , a microbiome researcher at the University of Chicago , told Global Health Asia-Pacific .
Probiotics are often hailed as a powerful tool to strengthen the immune system , with the implied idea that this would offer health benefits across the board . As a result , they are regularly recommended for a wide range of conditions , including gastrointestinal and cardiovascular disorders as well as cancer and allergies . But since they aren ’ t classed as medicines , they don ’ t have to go through the standard drug approval process , which requires companies to prove their product is safe and effective . The only requirement to sell probiotics is that they don ’ t cause harm .
The reality is that very few of these bold claims have been proven , especially in people without any health problem who are likely to account for the majority of those taking probiotics .
Despite these doubts , Dr Chang believes current research on how to strengthen the microbiome , including the use of probiotics , might eventually translate into a powerful approach for treating or lowering the risk for a host of conditions including gut problems , cancer , diabetes , and neurological diseases , but many questions still need to be answered before microbiome-based medicine can have significant clinical applications or lead to the development of health-promoting probiotics .
“ We have a lot more work ahead of us to have evidence-based data in order to advance the field ,” he said .
The essential function of the gut microbiome The gut microbiome comprises different species of tiny organisms including bacteria , viruses , and fungi that are unique to each individual and contribute to our normal bodily processes by digesting vital nutrients , producing important chemicals like vitamins , and stimulating the immune system .
For instance , gut bacteria are the only cells in the body that can form vitamin B12 , which helps make DNA , or the genetic material in all our cells , and prevent megaloblastic anemia , a blood condition that makes people weak and tired by reducing the amount of oxygen going to tissues .
In a study conducted by Dr Chang , baby mice whose microbiome was partially eradicated through antibiotics had a disrupted immune system and later in life developed colitis ( pain and swelling of the colon ) at a much greater rate and severity than mice with a healthy mix of microbes . The microbiome plays the essential role of teaching the immune system to recognise beneficial microbes early on to ensure it doesn ’ t negatively react to them by causing inflammation in the colon , he explained . If this recognition process is disrupted during the developmental stage , the immune system will attack those same microbes in the future once they enter the body .
A similar problem happens in humans when they are treated with antibiotics whose depleting effect on the microbiome might clear the way for the bacterium Clostridioides difficile ( C . diff .) to infect the colon , causing diarrhoea or even life-threatening consequences . “ A healthy microbiome is a deterrent for pathogens like C . diff . because good microbes form communities that prevent these pathogens from
50 ISSUE 5 | 2022 GlobalHealthAsiaPacific . com