Trans-fatty acid levels in erythrocytes in Europe

High, but not low levels of trans-fatty acids (TFA) in erythrocytes are associated with increased mortality. Current erythrocyte TFA levels in Europe are not known. TFA levels in samples submitted by physicians for erythrocyte omega-3 fatty acid analyses are reported, as analysed with a method (HS-Omega-3 Index(A (R))) previously used in pertinent prospective epidemiologic studies. From Germany, 6754 samples were included from 2008 through 2015, and 496 samples from 10 other European countries. In Germany, mean levels of C16:1n-7t, a marker for dairy and meat intake, decreased, as did mean levels of industrially produced (IP)-TFA, as did the percentage of individuals with IP-TFA > 1.04 %. Mean levels of IP-TFA in Austria and Switzerland were low before and after measures were taken to reduce them. Average levels of C16:1n-7t were low, and at levels associated with increased risk of death in previous studies. A limitation of our study is that samples were not obtained in a specific or representative manner. Levels of IP-TFA appear to be decreasing, as are those of ruminant-derived C16:1n-7t, a marker for dairy and meat intake. Few individuals had high levels of IP-TFA above a safe range, while many had low levels of C16:1n-7t. Our data argue against further action against TFA in the countries studied. More systematic biomarker-based studies are needed.