Effects oil cholesterol balance and LDL cholesterol in the rat of a soft-ripened cheese containing vegetable oils

Objective: The purpose of this study was to examine effects of a modified s oft-ripened cheese containing vegetable oils on cholesterol status, using t he rat as the experimental model and the traditional soft-ripened cheese as the control. Methods: Adult male Wistar rats (approximate to 370 g) were divided into tw o dietary groups (20 rats/group) and fed either the standard diet (STD, con taining traditional cheeses made from whole milk) or the experimental diet (EXP, containing modified cheeses made from the combination of skim milk wi th the following fat mixture: mill: fat/oleic acid-enriched sunflower oil/s oybean oil mixture). Lipids of the diets came solely from cheeses (14 g/100 g diet); the EXP diet contained (3-fold) less saturated fat, (2-fold) less cholesterol, and (15-fold) more phytosterols than the STD diet. Results: Although serum triglyceride and total cholesterol concentrations w ere not affected by the type of diet the EXP diet resulted in a significant reduction of LDL-cholesterol (31%, p<0.001) and a significant increase of HDL-cholesterol (11%, p<0.05), compared to the STD diet. Thus, a marked red uction (39%) of serum LDL/HDL cholesterol ratio was observed in the EXP gro up (p<0.001). In addition, the two quantitative balances (excreted/ingested ) of cholesterol and total neutral sterols (for which phytosterols were exc luded) were significantly higher by 183% and 174%, respectively for the EXP group, compared to the STD group (p<0.05). On another hand, rats fed the E XP diet excreted more cholesterol than they ingested dietary cholesterol (c holesterol balance > 1), indicating that those animals eliminated some endo genous cholesterol in their feces, while the opposite was true for rats fed the STD diet (cholesterol balance < 1). Finally, fecal bile salt concentra tion was not significantly different between the two dietary groups. Conclusions: The partial substitution of milk fat by vegetable oils in soft -ripened cheese resulted in a decreased blood LDL/HDL cholesterol ratio and an increased fecal excretion of endogenous cholesterol and neutral sterols and, thus, markedly improved its nutritional qualities. Therefore, the con sumption of the described modified cheese may meet the demand of subjects w ho wish to lower their risk for atherosclerosis and cardiovascular disease.