This metabolic study was designed to investigate the effects of mycoprotein on blood lipids. Mycoprotein is a food produced by continuous fermentation of Fusarium graminearum (Schwabe) on a carbohydrate substrate. Two groups of subjects with slightly raised cholesterol concentrations took part in the 3-wk study. The experimental group was fed mycoprotein in place of meat and the control diet contained meat. There was no change in plasma cholesterol in the control group but there was a 13% reduction in the mycoprotein group. Low-density lipoprotein (LDL) increased in the control group by 12% and decreased by 9% in the mycoprotein group. High-density lipoprotein (HDL) decreased by 11% in the control group but increased by 12% in the mycoprotein group. In each case the group ANOVA differences between variables were statistically significant. It is clear from these results that lipid variables are advantageously altered by mycoprotein consumption.