Why are trans fatty acids considered unhealthy?
Over the last decade or so, extensive research has shown that trans fatty acid consumption, especially the trans fatty acids resulting from partial hydrogenation, are positively linked to higher incidence from certain chronic diseases. There is fairly uniform agreement, that trans fatty acids increase LDL cholesterol levels (“bad” cholesterol) and decrease HDL cholesterol levels (“good” cholesterol). In fact it is believed that trans fatty acid are worse that saturated fatty acids in this regard.
