Dietary-fish effects on serum lipids and apolipoproteins, a controlled study

In Maastricht and Zeist, The Netherlands, and Tromsø, Norway, a well-controlled study was performed on the effect of a fish-enriched diet on serum lipids, apolipoproteins A-1 and B, and fatty acid compositions of serum triglycerides and cholesterol esters. For 6 wk healthy male volunteers were given a daily dietary supplement consisting of 135 g mackerel paste (experimental group, n = 42) or meat paste (control group, n = 42). Dietary adherence was calculated on the basis of urinary excretion of a standard amount of lithium added to the supplements. Average compliance was 80%. Low-density-lipoprotein (LDL) and total serum cholesterol concentrations were unaffected. High-density-lipoprotein (HDL) cholesterol increased to a comparable degree in both groups. Triglyceride content of serum decreased in the fish group. Apolipoproteins A-1 and B (both in Maastricht subjects only) were only slightly affected. In the mackerel group the n-3 fatty acids increased significantly in serum cholesterol esters and triglycerides; the n-6 fatty acids decreased in cholesterol esters only.