An international study led by scientists at Monash University in Australia yielded evidence confirming that low fiber diets may lead to high blood pressure, a disease afflicting extremely sizeable portions of the global population.
 
If left untreated, high blood pressure can lead to stroke, myocardial infarction, a stiffening of the arteries and the muscles of the heart, and a stiffening of the kidneys, reducing their function. It’s the most common risk factor for cardiovascular disease.
 
The study, which was published last week in Circulation, used mice to test the difference between high- and low-resistant starch diets.
 
Resistant starches are a type of prebiotic fiber, which resists digestion until it reaches the large intestine, where it feeds bacteria that are considered to have health benefits.
 
The results found that mice fed a low fiber diet were more predisposed to high blood pressure. Researchers performed fecal transplants on mice without any microbes, and found that only recipients of low fiber microbes went on to develop higher blood pressure.
 
Professor David Kaye, the Director of Cardiology at Melbourne, Australia’s Alfred Hospital and head of the Baker Institute of Heart Failure, co-led the study. Kaye said that although a high-fiber diet may be protective against high blood pressure, the mechanism for this action remains uncertain.
 
“One of the most unique findings of the study is that the bacterial profile of the gut, called the gut microbiome, is closely associated with blood pressure and this link is the result of chemicals released by gut bacteria into the circulation,” Kaye said.
 
Researchers involved in this study intend to follow up on the results with trials on humans.
 
“High blood pressure continues to be a major risk factor for cardiovascular death,” lead study author Francine Marques said. “A diet poor in fiber is associated with prevalence of high blood pressure, but this study is changing the concept of fiber intake being only protective: lack of fiber can actually contribute to high blood pressure and cardiovascular disease, and this happens via the gut microbiota.”
 
“The findings reinforce the need for a diet high in fiber and also point to new potential targets for the prevention and treatment of cardiovascular disease,” Marques added.
 
Marques is currently leading a clinical trial funded by Australia’s National Heart Foundation to determine if a modified prebiotic fiber supplement, which produces high levels of metabolites as a result of microbial fermentation, could be used as a new strategy to lower blood pressure.