Researchers from the Agricultural Research Service and their colleagues found that healthy adults who consume at least 8 to 10 grams of soluble fiber daily have less antibiotic-resistant bacteria in their stomachs.
With the widely held belief that the issue of antimicrobial resistance (AMR), the term used to refer to bacteria, viruses, and fungi that are resistant to antibiotics, is likely to worsen throughout the coming decades, microbes that have resistance to various commonly used antibiotics such as tetracycline and aminoglycoside are a significant source of risk for people worldwide.
People’s gut microbiome, where the microorganisms are known to possess genetically programmed ways to survive contact with antibiotics, is a major contributor to antimicrobial resistance.
“And 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 fiber, that some Americans already eat,” explained research molecular biologist Danielle Lemay with the ARS Western Human Nutrition Research Center in Davis, California, and leader of the study.
In this study, the researchers searched for precise correlations between adult diets’ levels of fiber and animal protein and the levels of antibiotic resistance genes in the microorganisms of the human gut.
The researchers discovered a strong correlation between regular consumption of a diet high in fiber and low in protein, notably from beef and pig, and reduced levels of antimicrobial resistance genes (ARG) in their gut microorganisms.
Strict anaerobic microorganisms, which are bacteria that can not grow when oxygen is present and are a sign of a healthy gut with low inflammation, were more prevalent among those with the lowest amounts of ARG in their gut microbiomes. Anaerobes discovered in the Clostridiaceae family of bacteria were the most numerous.
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.
Danielle Lemay
However, dietary animal protein intake was not a significant predictor of elevated levels of ARG. The diet’s higher soluble fiber content was shown to be associated with lower levels of ARGs, according to the most convincing data.
“Surprisingly, the most important predictor of low levels of ARG, even more than fiber, 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 fiber for maximum benefit,” Lemay added.
In addition to some fruits and vegetables like carrots, berries, artichokes, broccoli, and winter squash, soluble fiber can also be found in grains like barley and oats, legumes like beans, lentils, and peas, seeds (like chia seeds), nuts, and some seeds and legumes. As its name implies, soluble fiber dissolves in water.
On the other hand, it was discovered that groups with low and medium levels of ARG had considerably more diversified gut microbiomes than those with the highest amounts of ARG in their microbiomes.
“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,” Lemay said.
In total, 290 healthy adults participated in the study.
“But 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,” Lemay said.
“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.”