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Objective: To measure the relative effects of each of four phytosterol ester-enriched low-fat foods (bread, breakfast cereal, milk and yoghurt) on serum lipids, plasma phytosterols and carotenoids. Design: Three research centres undertook a randomised, incomplete crossover, single-blind study consisting of four treatment periods of 3 weeks each, one of which was a control period. Each sterol-enriched test food provided 1.6 g/day of phytosterols as sterol esters. Setting: General Community. Subjects: In all 58, free-living men and women with mean age (s.d.) 54 (8) y, moderately elevated plasma total cholesterol 6.2 (0.7) mmol/l and body mass index 26.2 (3.0) kg/m 2 . Main outcome measures: Serum lipids, plasma phytosterols and carotenoids. Results: Serum total and LDL cholesterol levels were significantly lowered by consumption of phytosterol-enriched foods: milk (8.7 and 15.9%) and yoghurt (5.6 and 8.6%). Serum LDL cholesterol levels fell significantly by 6.5% with bread and 5.4% with cereal. They were both significantly less efficacious than sterol-enriched milk (Po0.001). Plasma sitosterol increased by 17-23% and campesterol by 48-52% with phytosterol-enriched milk and bread. Lipid-adjusted b-carotene was lowered by 5-10% by sterols in bread and milk, respectively. Conclusions: This is the first study to demonstrate that cholesterol-lowering effects of plant sterol esters may differ according to the food matrix. Plant sterols in low-fat milk was almost three times more effective than in bread and cereal. Despite phytosterolenriched cereal products resulting in lower serum cholesterol reductions compared to sterol-enriched milk, the detection of similar changes in plasma phytosterols demonstrated that such products still delivered and released phytosterols to the gut.

The objective of this study was to measure the effects on serum lipids and plasma phytosterols of 6.6 g/day phytosterols from three foods (bread, breakfast cereal, and spread) consumed for 12 weeks compared with a diet that was not enriched with phytosterols. Thirty-five subjects undertook a nonrandomized, single-blind study consisting of a 2 week baseline period, 6 weeks on high-phytosterol intake, 6 weeks on high-phytosterol intake plus increased fruit and vegetable intake, and a final 2 week washout period. Serum total cholesterol decreased by 8.3% from 6.59 to 6.04 mmol/l, and LDL cholesterol decreased by 12.6% from 4.44 to 3.88 mmol/l. Plasma phytosterol levels increased by 45% (sitosterol) and 105% (campesterol). Cholesterol-adjusted plasma ␣ -and ␤ -carotene levels decreased by 19-23%, lutein by 14%, and lycopene by 11%. Levels of ␣ -carotene and lutein increased with extra fruit and vegetables. Only lycopene failed to increase during the washout phase. There were no significant changes in biochemical parameters. Serum LDL cholesterol lowering with 6.6 g/day ingested phytosterols was in the range seen with 1.6-3.2 g/day phytosterols. Lowering of plasma carotenoids was greater than that seen with lower phytosterol intake and was partially reversed by increased fruit and vegetable intake. There are extensive data confirming the effectiveness of esterified phytosterols in margarines, with LDL cholesterol lowering of 10-15% with a dose of 1.6-2.4 g/day sterol (1-6). There are few published data (7, 8) on the short-term use of higher amounts of plant sterols (8.6-9 g/day) in margarines, and there is some evidence that carotenoid lowering is greater on a high dose of phytosterol without enhancement of cholesterol lowering (7). It is not known if increased fruit and vegetables can restore the plasma level of carotenoids after a higher intake of phytosterols, although they can achieve this with a more usual intake of phytosterols (4). The aim of this study was to examine the effect of 6.6 g/day phytosterols in bread, breakfast cereals, and margarine over a 12 week period, to examine the role of extra fruit and vegetables in ameliorating the decrease in carotenoid concentration, and to examine the changes in carotenoid concentrations after cessation of phytosterol ingestion. METHODS SubjectsThirty-five mildly hypercholesterolemic men and women were recruited and entered the study. The study was conducted at two clinical research centers: the Commonwealth Scientific and Industrial Research Organization (CSIRO) Division of Health Sciences and Nutrition in Adelaide and the Baker Medical Research Institute in Melbourne. Subjects were screened on the basis of the following inclusion criteria: age, 20-75 years; body mass index (BMI), Ͻ 31; total serum cholesterol, Ͼ 5.0 mmol/l and Ͻ 7.5 mmol/l; and serum triglycerides, Ͻ 4.5 mmol/l. No lipid-lowering medication was permitted, nor was medication likely to affect lipid metabolism. Subjects were not diabetic, had normal thyroid status, and had no metabolic disorde...

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