Canadian scientists are joining with international colleagues to lead new insights into the health implications of different types of trans fat.
The latest research builds on ground-breaking new knowledge on a special 'family' of natural trans fats that are produced by ruminant animals such as dairy and beef cattle, goats and sheep, and found in the milk and meat from these animals. The findings strengthen the evidence that, unlike industrial trans fats, these natural ruminant trans fats are not harmful and may in fact have health-enhancing potential.
The key findings were presented at the 10th Congress for the International Society for the Study of Fatty Acids & Lipids (ISSFAL), May 26-30 in Vancouver.
"We are learning there is a very important public health message to convey about ruminant natural trans fats and how these are different from the industrial trans fats that have been targeted as harmful to health," says Dr. Spencer Proctor, Director of the Metabolic and Cardiovascular Diseases Laboratory at the University of Alberta in Canada. "The research indicates that consuming these natural trans fats as part of a balanced diet is not a health concern. On the contrary, there is increasing evidence these are 'good fats' and could be fundamentally health-enhancing. They should not be an unintended target of the bid to rid the diet of trans fats."
ISSFAL is an International Scientific Society established in 1991, with members from more than 40 countries including scientists, medical professionals, educators, administrators, communicators and others with an interest in the health effects of dietary fats, oils and lipids. Among a number of key functions, ISSFAL has taken on an important role in interpreting the new facts in each of these areas into sound nutritional advice for the public.
Proctor chaired a Symposium at the ISSFAL Congress that focused on the health implications of natural ruminant trans fatty acids. Also presenting supporting findings were Dr. Jean-Michel Chardigny, National Institute for Agricultural Research (INRA), France; and Dr. Marianne Uhre Jakobsen, Associate Professor, Public Health, Aarhus University, Denmark.
The research to date is based on a strong foundation of animal model studies as well as a growing number of human studies, say these scientists. "Our knowledge of natural trans fats is relatively recent and we will continue to learn more about the human health implications," says Chardigny. "But clearly we know they are different from industrial trans fats and should not be painted with the same brush."
As a leading example, Chardigny presented findings of his meta-analysis of 13 human intervention studies that have examined the impact of natural trans fats on cardiovascular health risk factors. While there is a large body of research confirming detrimental effects of industrial trans fats, the research to date on natural trans fats has revealed no such effects.
"There is no association between natural trans fats intake and cholesterol-dependent cardiovascular risk factors," says Chardigny.
This conclusion was further supported by Jakobsen's review of observational epidemiologic studies. "The findings indicate that intake of natural trans fats is not associated with coronary heart disease within the range of intake in the general population."
The scientific knowledge points to the need to clearly differentiate between natural and industrial trans fats on food labels and in health recommendations, say these scientists. At meetings in and around ISSFAL they and colleagues are exploring approaches for further international collaboration among researchers as well as health and food regulatory authorities to make progress on this front.
"We want to help the public better understand the very different health implications of the two different categories of trans fats, including through the nutrition information they get on food labels," says Proctor. "We're confident we can achieve that by continuing to work together."