SHORT-TERM ADMINISTRATION OF TALL OIL PHYTOSTEROLS IMPROVES PLASMA-LIPID PROFILES IN SUBJECTS WITH DIFFERENT CHOLESTEROL LEVELS

To assess the short-term cholesterol-lowering potential of sitostanol- containing tall oil plant sterols, 22 subjects consumed fixed-food die ts over two 10-day periods with or without 21.2 mg/kg body weight/d ta ll oil phytosterols (sitosterol 62%, sitostanol 21%, campesterol 16%, and campestanol 1%) in a randomized crossover study design. On day 10 of each diet, plasma lipoprotein cholesterol levels, plasma phytostero l concentrations, and cholesterol biosynthesis rates were determined. Total cholesterol (TC) and low-density lipoprotein (LDL) cholesterol l evels were lower (P < .01) after administration of tall oil phytostero l (4.7 +/- 0.3 and 3.0 +/- 0.3 mmol/L, respectively) versus placebo (5 .0 +/- 0.3 and 3.2 +/- 0.3 mmol/L, respectively). Tall oil treatment h ad no effect on the plasma high-density lipoprotein (HDL) cholesterol level (1.1 +/- 0.1 mmol/L) versus placebo (1.1 +/- 0.1 mmol/L). Simila rly, plasma triglyceride (TG) levels did not differ between tall oil ( 1.3 +/- 0.2 mmol/L) and placebo (1.4 +/- 0.2 mmol/L) treatments. Plasm a campesterol (15.8 +/- 3.7 mmol/mol cholesterol) and sitosterol (6.0 +/- 2.1 mmol/mol cholesterol) levels were not different after tall oil treatment versus placebo treatment (15.4 +/- 2.3 and 6.4 +/- 2.0 mmol /mol cholesterol, respectively). Plasma sitostanol levels were essenti ally undetectable. No difference was observed in cholesterol biosynthe sis between tall oil (0.045 +/- 0.004 pools/d) and placebo (0.034 +/- 0.004 pools/d) treatments; however, the effect of treatments in subjec ts with different cholesterol levels varied. In subjects with lower ch olesterol values, the red blood cell cholesterol fractional synthesis rate (FSR) increased from 0.0291 +/- 0.0054 pools/d after placebo to 0 .0509 +/- 0.0049 pools/d (P < .05) after phytosterol treatment. In sub jects with higher cholesterol values, the red blood cell cholesterol F SR did not change significantly after treatment. These results demonst rate the short-term efficacy of tall oil plant sterols as cholesterol- lowering agents. Copyright (C) 1998 by W.B. Saunders Company.