All dietary fats are not created equal. Some types of fats have been linked to ailments like heart disease and diabetes, while others, like those often found in plants and fish, have well documented health benefits.
So why do our bodies respond so destructively to some fats but not others?
A new hypothesis described in latest issue of The Quarterly Review of Biology suggests the answer may lie in how different fats interact with the microbes in our guts. According to researchers from the University of New Mexico and Northwestern University, some fats may encourage the growth of harmful bacteria in the digestive system. Our bodies have evolved to recognize those fats and launch an immune response to preempt the impeding changes in harmful bacteria. The result is low-level inflammation that, over the long term, causes chronic disease.
"Although the inflammatory effects of [fats] are well documented, it is less well appreciated that they also influence bacterial survival and proliferation in the gastrointestinal tract," write the researchers, led by Joe Alcock, of the University of New Mexico Department of Emergency Medicine and VA Medical Center.
Some fatsmostly unsaturated fatsactually have strong antimicrobial properties. They react chemically with bacterial cell membranes, weakening them. "If you expose unsaturated fats on bacteria, the bacteria have a tendency to lyse. The combination of long chain unsaturated fats, especially omega-3 fatty acids, and innate host defenses like gastric acid and antimicrobial peptides, is particularly lethal to pathogenic bacteria," Alcock said. Saturated fats on the other hand generally lack those antimicrobial properties, and in fact can provide a carbon source that bacteria need to grow and flourish.
And it's these differing microbial effects, Alcock believes, that are at the root of why some fats are inflammatory and some aren't. To test that notion, the researcher
|Contact: Joe Alcock|
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