Milk is known as a complete liquid food. A component in milk has been linked with decrease inflammatory disease.
One of the isomers of conjugated linoleic acid, a group of fatty acids found in milk, is a natural regulator of the COX-2 protein, which plays a significant role in inflammatory disease such as arthritis and cancer, according to a study published by University of Wisconsin-Madison researchers.
"It's clear from previous research that conjugated linoleic acid, or CLA, prevents inflammatory damage resulting from immune response," says Mark Cook, a professor of animal science in UW-Madison's College of Agricultural and Life Sciences. "We've identified the biochemical mechanism by which this occurs."
CLA, which is synthesized by microbial fermentation in the rumen of dairy cows, exists naturally in a number of structural forms. Cook's team determined that one of the variants inhibits the COX-2 protein by blocking a key cellular pathway. The COX-2 protein is known to play a significant role in many inflammatory diseases and is an important drug target for treating arthritis and cancer, Cook says.
While the amount of the anti-inflammatory isomer of CLA in milk is small relative to other fatty acids in milk, there may still be enough to elicit an effect if someone consumes dairy products every day, says Cook. He is planning a study, in collaboration with researchers in the dairy science and food science departments, to determine whether the amount of anti-inflammatory CLA in milk can be increased by changing dairy cow diets.
However, Cook is interested in another approach: Using CLA as a natural way to prevent "collateral damage" from the immune system's response to invading pathogens. "The ideal solution is to let the immune system fight bacteria, but at the same time to maintain the overall health of the system," he says.
Cook is one of many UW-Madison researchers who are interested in the health benefits of CLA. Others include Michael Pariza, director of the Food Research Institute and chair of the food microbiology and toxicology department; James Ntambi of the biochemistry department; and Dale Schoeller of the nutritional sciences department.
Source: UW-Madison; Food Research Institute