Olive oil, canola oil, and vegetable oil largely consist of unsaturated fatty acids, whereas animal fat is richer in the saturated ones. After a meal, carbohydrates are the primary source of energy production by the heart but under fasting conditions, free fatty acids become the major energy producer. 

Saturated fat is considered detrimental to heart health overall because saturated fatty acids are toxic to cells while unsaturated fatty acids are harmless and also provide protection against the damage done by saturated fatty acids.

A new study says it has a direct impact on cardiac muscle. Studies conducted on many cell lines have indicated that saturated fatty acids can cause cell death involving endoplasmic reticulum stress (ER stress), a cellular process known to be involved in the development of many diseases. 

A new paper says that there are striking differences in the accumulation of saturated and unsaturated fatty acids in cardiac muscle cells, and that saturated fatty acids induce the death of these cells through the ER stress. In contrast, unsaturated fatty acids protect the same cells from such damage.

A research group from the Montreal Heart Institute in Canada, led by Dr. Nicolas Bousette, evaluated the impact of palmitate and oleate on cellular fatty acid absorption, triglyceride synthesis, intracellular lipid distribution, ER stress, and cell death in primary cardiomyocytes. This is the first time that such phenomena were observed in cells directly derived from the heart, validating a critical role for saturated fatty acids in the development of heart diseases.

Given a primary role for lipid metabolism in the development of type II diabetes, the current finding might suggest a probable role for saturated fatty acids in the development of heart conditions among diabetic patients.

The current results and future research in this direction might improve our understanding on the possible connection between intracardiomyocyte lipid accumulation and the development of diabetic cardiomyopathy.

Citation: Taha Haffar, Félix-Antoine Bérubé-Simard, Jean-Claude Tardif, Nicolas Bousette, 'Saturated fatty acids induce endoplasmic reticulum stress in primary cardiomyocytes', Endoplasmic Reticulum Stress in Diseases, Volume 2, Issue 1, ISSN (Online) 2300-4266, DOI: 10.1515/ersc-2015-0004, March 2015