Divergent changes in serum sterols during a strict uncooked vegan diet in patients with rheumatoid arthritis

The effects of a strict uncooked vegan diet on serum lipid and sterol conce ntrations were studied in patients with rheumatoid arthritis. The subjects were randomized into a vegan diet group (n 16), who consumed a vegan diet f or 2-3 months, or into a control group (n 13), who continued their usual om nivorous diets. Serum total and LDL-cholesterol and -phospholipid concentra tions were significantly decreased by the vegan diet. The levels of serum c holestanol and lathosterol also decreased, but serum cholestanol:total chol esterol and lathosterol:total cholesterol did not change. The effect of a v egan diet on serum plant sterols was divergent as the concentration of camp esterol decreased while that of sitosterol increased. This effect resulted in a significantly greater sitosterol:campesterol value in the vegan diet g roup than in the control group (1.48 (SD 0.39) v. 0.72 (SD 0.14); P < 0.001 ). A higher concentration of campesterol compared with sitosterol is normal in omnivorous subjects and can be explained by lower absorption and esteri fication rates of sitosterol. Our results suggest that a strict uncooked ve gan diet changes the relative absorption rates of these sterols and/or thei r biliary clearance.