Eating a high fibre diet may be an effective way to reduce antimicrobial resistance (AMR), with research suggesting that consuming soluble fibre reduces antibiotic resistant microbes in the gut.
A study performed by the Agricultural Research Service (ARS) has discovered that eating a high fibre diet – consisting of a minimum of 8-10 grams of soluble fibre per day – may be able to reduce the volume of antibiotic resistant gut microbes. The research may help pioneer novel dietary interventions to combat the imminent AMR health crisis.
Danielle Lemay, a molecular research biologist at the ARS Western Human Nutrition Research Center and leader of the study, said: “The results lead directly to the idea that modifying the diet has the potential to be a new weapon in the fight against antimicrobial resistance. And we’re not talking about eating some exotic diet either, but a diverse diet, adequate in fibre, that some Americans already eat.”
The study findings are published in mBio.
AMR in the gut microbiome
Antimicrobial resistance occurs when bacteria, viruses, and fungi cannot be killed by the antibiotics employed to destroy them as they have developed resistance over time. AMR is forecasted to get significantly worse in the coming years and is primarily influenced by the gut microbiome, in which microbes are known to carry genetically encoded strategies to survive battles with antibiotics. Microbes such as tetracycline and aminoglycoside have already developed resistance to many commonly used antibiotics and are a significant threat to public health.
Impacts of a high fibre diet
Soluble fibre dissolves in water and is the primary type of fibre found in grains like barley and oats; legumes like beans, lentils and peas, seeds like chia seeds and nuts; and some fruits and vegetables, such as carrots, berries, artichokes, broccoli, and winter squash.
For their investigation, the team utilised data from 290 healthy adult participants, analysing the relationships between levels of antimicrobial resistance genes (ARG) in their gut microbes and both a high fibre diet and a high animal protein diet.
The results demonstrated that eating a high fibre diet that was also low in protein – specifically from beef and pork – was associated with significantly lower levels of ARG in their gut microbes. Individuals with the lowest ARG in their gut microbiomes had a higher amount of strict anaerobic microbes – bacteria that cannot thrive when oxygen is present and are linked with a healthy gut and low inflammation. Moreover, the Clostridiaceae family of bacteria were the anaerobes found most.
The study signified that animal protein in the diet was not the strongest predictor of high levels of ARG, with higher amounts of soluble fibre showing the strongest association with low ARG levels. The participants with the highest ARG levels were those found to have a considerably less diverse gut microbiome than those with low and medium levels of ARG.
Lemay concluded: “Surprisingly, the most important predictor of low levels of ARG, even more than fibre, was the diversity of the diet. This suggests that we may want to eat from diverse sources of foods that tend to be higher in soluble fibre for maximum benefit. Our diets provide food for gut microbes. This all suggests that what we eat might be a solution to reduce antimicrobial resistance by modifying the gut microbiome.
“This is still just a beginning because what we did was an observational study rather than a study in which we provided a particular diet for subjects to eat, which would allow more head-to-head comparisons. In the end, dietary interventions may be useful in lessening the burden of antimicrobial resistance and might ultimately motivate dietary guidelines that will consider how nutrition could reduce the risk of antibiotic resistant infections.”