Plasma lipoprotein changes were evaluated in 65 type II patients undergoing sequential 4-week dietary treatments with: (I) standard low-lipid diet; (II) low-lipid diet with total replacement of animal proteins with textured soy proteins containing 6% of lecithin (L-TVP); (III) standard low-lipid diet; (IV) low-lipid diet with a 50% substitution of animal proteins with L-TVP. Total cholesterolemia was significantly reduced in both periods of L-TVP administration: -18.6% during phase II (total replacement) and -13.2% during phase IV (partial replacement). High-density lipoprotein (HDL) cholesterol levels tended to increase during L-TVP administration. However, only patients in the mid- and low tertiles for HDL cholesterolemia showed a significant increase of HDL levels during L-TVP. This 'normalizing' activity of L-TVP on plasma lipoproteins, even when administered as a partial dietary substituent, may be of clinical interest for subgroups of patients at high vascular risk.