Free plant sterol-supplemented mayonnaise was examined for its capacity to lower serum cholesterol and evaluation was made of its mayonnaise. This evaluation was done via a double-blind, placebo-controlled study using forty-six normocholesterolemic and mildly hypercholesterolemic Japanese persons (total cholesterol ≥ 200 mg/dL) randomly divided into two groups. The plant sterol (PS) ( ) group was given 15 g mayonnaise containing 800 mg free PS daily, while the PS ( ) group did 15 g mayonnaise daily for 12 weeks. Serum total cholesterol (TC) and low-density lipoprotein (LDL)-C were reduced by 4.3 and 9.2 in the PS ( ) group, on completion of the 12-week period. At that time, serum apolipoprotein (Apo) B had been reduced by 3.6 in the PS ( ) group, this being significantly more compared to the PS ( ) group. Serum remnant-like particle (RLP)-C and Apo E did not change significantly in either groups. Decrease in TC and LDL-C with PS ( ) group was greater for the serum TC ≥ 220 mg/dL subjects compared to the TC 220 mg/dL subjects. Serum vitamin A, 25 (OH) vitamin D, and vitamin K 1 underwent no change throughout the study. Serum a-tocopherol reduction was the same in the two groups. The PS ( ) group showed significant increase in serum b-sitosterol while b-sitosterol remained within normal range throughout the study period. For complete blood count (CBC) and blood biochemistry, all values were normal in the two groups. Free plant sterol-supplemented mayonnaise is thus shown a safe food for reducing serum TC and LDL-C. This mayonnaise should prove applicable for reducing serum LDL-C in mildly hypercholesterolemic persons.

SummaryWe performed in vitro, animal, and human studies to clarify the effect of mayonnaise on ␤ -carotene intake and its mechanism. In an artificial gastric juice model, we examined the transfer of ␤ -carotene from grated carrot to mayonnaise or vegetable oil. Mayonnaise was more easily dispersed in artificial gastric juice than vegetable oil. The ␤ -carotene concentration was greater in mayonnaise than vegetable oil. In rats, the postprandial serum ␤ -carotene concentration in the mayonnaise group ( ␤ -carotene with mayonnaise) was higher than that in the control ( ␤ -carotene only) and vegetable oil ( ␤ -carotene with vegetable oil) groups. Continuous feeding of dietary ␤ -carotene (14 d), employing mayonnaise or egg yolk, resulted in an increased accumulation of ␤ -carotene in the liver. In a human study, diets were provided in the form of (1) carrot as a control (CON), (2) carrot juice (JU), (3) carrot with oil (OIL) and (4) carrot with mayonnaise (MS). Following collection of fasting blood samples, nine adult males consumed one of the four diets in random order. Fasting and postprandial changes in serum ␤ -carotene were assessed at 2, 3, 4, 6 and 8 h following ingestion of each diet. The incremental areas under the curves of serum ␤ -carotene concentration were higher following MS than following both CON and JU. In conclusion, we suggest that mayonnaise contributes to raising the serum ␤ -carotene concentration when consumed with carrots rich in ␤ -carotene, and that its mechanism is related to the emulsifying property of the egg yolk contained in mayonnaise.

Summary To clarify the effects of different physical forms of oil on postprandial serum lutein/zeaxanthin and ␤ -carotene concentrations, we performed a vegetable meal loading test. Eighteen healthy subjects participated in the test, which consisted of broccoli as a control (CON) meal, broccoli with oil (OIL), and broccoli with mayonnaise (MS), consumed in random order. After collection of fasting blood samples, subjects consumed one of the three test meals. Fasting and postprandial changes in serum carotenoids were assessed 2, 4, and 6 h after ingestion of each test meal. Serum lutein/zeaxanthin and ␤ -carotene concentrations were measured. Although no significant change was noted after the CON meal, the serum lutein/zeaxanthin concentration was higher at 4 h after consumption of the OIL meal, and at 2, 4 and 6 h after consumption of the MS meal, as compared with the fasting state. Serum ␤ -carotene concentrations did not change after ingestion of either the CON or the OIL meal but were elevated 2, 4, and 6 h after MS ingestion as compared with the fasting state. The incremental areas under the curves (IAUCs) of serum lutein/zeaxanthin and ␤ -carotene concentrations were higher after the MS meal than after the CON meal. IAUCs after the OIL meal exhibited no statistically significant differences from the CON and MS meals. We suggest that mayonnaise contributes to increase serum lutein/zeaxanthin and ␤ -carotene concentrations when consumed with vegetables rich in these carotenoids.

We examined the minimal effective dose on serum cholesterol concentration and the safety of dressing containing plant sterol in humans. Exp.1: Sixty-eight healthy Japanese males (total cholesterol (TC) 170 mg/dL) were randomly divided into four groups, and were given 0, 400, 800 or 1200 mg/day of plant sterol in 15 g dressing for 4 weeks followed by the washout period of 4 weeks. Although there were no significant differences in serum TC and low-density lipoprotein cholesterol (LDL-C) concentrations among all groups after feeding plant sterol for 4 weeks, in 36 subjects with TC 220 mg/dL, serum LDL-C concentration tended to reduce when received 800 or 1200 mg of plant sterol, and the difference between 0 and 1200 mg groups was statistically significant. The difference between 0 and 800 mg groups was near significant (p=0.053). Intake of 400 mg of plant sterol did not change serum LDL-C concentration. Exp.2: Twenty-one healthy Japanese subjects (TC 180 mg/dL, 10 men, 11 women) were given 2400 mg/day of plant sterol in 45 g dressing for 4 weeks. Clinical data were all remained normal. These results indicated that minimal effective dose of the plant sterol on serum cholesterol concentration in healthy male subjects is around 800 mg/day, and intake of 2400 mg/day of plant sterol is regarded to be safe.

For examination of the title parameters, study was made in which forty healthy male subjects (serum cholesterol concentration 170 309 mg/dL) were fed 0, 200, 400, 600, or 800 mg/day of free plant sterol supplemented in mayonnaise for 4 consecutive weeks. Only the 800 mg/day group significantly reduced serum cholesterol by the paired t-test (Exp.1). Thirtytwo healthy males (serum cholesterol, 184 285 mg/dL) were made to consume plant sterol as ester at 0, 800, 1600, or 2400 mg/day. In all cases at more than 800 mg/day reduction in serum cholesterol was noted though without significant difference with paired t-test results (Exp.2). Subsequent to the mayonnaise consumption, normal diets were resumed for a period of 4 weeks. Total cholesterol showed original values at the end of this period. Plant sterol is thus shown to be a dietary component capable of reducing cholesterol by these results. Fifteen healthy subjects (males 10, females 5) were made to consume free plant sterol supplemented in mayonnaise at 2400 mg/day for 4 consecutive weeks. No change in serum vitamin A or vitamin E levels was observed at 2400 mg consumption. At 2400 mg, a significant increase in serum b-sitosterol was noted though it was markedly less than b-sitosterolemia. Clinical trial results, in all cases, were normal (Exp.3). The minimal effective dose of plant sterol on serum cholesterol concentration would thus appear to be 800 mg/day. At 2400 mg/day in mayonnaise, physiological and biochemical safety markers in serum would not undergo abnormal change.