The latest scientific contribution to the on-going saga of butter or margarine comes courtesy of the British Medical Journal. The research paper surveys previously published research and presents the findings as a meta-study.
With the new study, a Canadian research group set out to: “systematically review associations between intake of saturated fat and trans unsaturated fat and all cause mortality, cardiovascular disease (CVD) and associated mortality, coronary heart disease (CHD) and associated mortality, ischemic stroke, and type 2 diabetes.”
With “saturated fat” read butter and with “trans fat” and “trans unsaturated fat” read margarine. The research found:
Saturated fats are not associated with cardiovascular disease, coronary heart disease, ischemic stroke (strokes from blood clots), or type 2 diabetes;
Trans fats are associated with cardiovascular disease and coronary heart disease mortality.
The difference was that animal fats, as found in butter, are unlikely to increase the risk of death; trans fats, as found in many margarines, increase the risk of death by 34 percent. The reason that trans fats are a risk is because they work on the body’s inflammatory process. Trans fats are not commonly found in nature; they were developed in the 1890’s by chemist Paul Sabatier.
Commenting on the results, Doctor Russell de Souza, an assistant professor in the Department of Clinical Epidemiology and Biostatistics, at McMaster University in Canada, told The Daily Telegraph: “For years everyone has been advised to cut out fats. Trans fats have no health benefits and pose a significant risk for heart disease, but the case for saturated fat is less clear.”
Importantly, the researchers are not calling on people to eat more butter. Intake of saturated fats can cause other ill-health effects. However, the researchers are calling for a review of health policy, especially advice that encourages people to supplement margarine in place of butter.
The paper is titled “Intake of saturated and trans unsaturated fatty acids and risk of all cause mortality, cardiovascular disease, and type 2 diabetes: systematic review and meta-analysis of observational studies”, and it can be accessed in full here.
