New study results from the University of Alberta indicate that natural trans fat found in dairy and beef products may reduce inflammation, a key risk factor for heart disease.
In a three-week animal model trial, researchers succeeded in reducing inflammation from elevated to normal levels by feeding dietary vaccenic acid (VA), a type of natural trans fat found in dairy and beef products.
“The reduction in inflammation was substantial and clearly the result of feeding the dietary VA,” says Catherine Field, a lead member of the research team in the university’s Alberta Institute for Human Nutrition (AIHN), which conducted the study.
“The findings are quite significant because inflammation is now recognized as an independent risk factor for heart disease. Our results indicate that natural trans fat in beef and milk can reduce this risk.”
Human clinical trials are needed to confirm the human health implications of dietary VA, cautions Field. However the growing base of science in the area of natural trans fat indicates it should not be considered harmful. In fact, natural trans fat shows significant health-enhancing potential.
“The perception is that trans fat is linked with an increased risk of heart disease and other chronic conditions,” says Field. “The science is quite conclusive that is the case with industrially processed trans fat, but this study and a growing body of others indicate this is not the case with the natural trans fat. We need to recognize there is a clear difference.”
The inflammation findings were part of a trial examining the immune response related to dietary VA. It was conducted using a model JCR: LA-cp rat species, which is a species bred to provide a model for metabolic syndrome – a human health condition associated with increased risk of cardiovascular disease and other health threats.
Key indicators of inflammation were measured among both the metabolic syndrome model group and a lean model group. In the metabolic syndrome group, dietary VA normalized the production of these indicators from high levels to levels similar to those seen in the lean group.
VA also altered other parameters of immune function in the metabolic syndrome group in a positive direction toward those of the lean group. Complete findings were recently published in the British Journal of Nutrition.
This study served as a companion to an earlier study by the AIHN focused on lipid response related to dietary VA in the same model. In the lipid study, among a metabolic syndrome group receiving dietary VA in a 16-week trial, triglyceride levels were reduced by more than 50 per cent, total cholesterol was reduced by approximately 30 per cent and LDL (i. e. bad) cholesterol was reduced by 25 per cent.
The findings set the stage for future human clinical trials of dietary VA targeted by AIHN and have major implications for how health practitioners and the public at large view natural trans fats. VA is produced only by ruminant animals such as dairy and beef cattle. It is estimated to contribute 80 to 90 per cent of ruminant-based trans fat content in the North American diet.
The remaining portion of natural trans fat is conjugated linoleic acid (CLA), which in separate animal model studies by AIHN and others has been shown to have broad health-enhancing potential.
These two predominant forms of natural trans fat are closely related. In fact, a portion of dietary VA is known to convert into CLA in humans.
Field and colleagues are participants in the CLA Network. More information on the CLA Network is available at www.clanetwork.com,including a new feature article titled “New health-boosting power found in dairy foods.”