Plants sterols are known to inhibit cholesterol absorption, and this study investigated the effect of plant sterol-containing oil on cholesterol-containing foods. Oil containing 1.5% plant sterols was given in a scrambled egg sandwich (test food) to 15 healthy male adults (38.3 years average age) to investigate the effect of the sterols on the serum lipids levels. A scrambled egg sandwich containing soybean oil alone was used as the control food. There was no significant difference between the test food and control food for the subjects as a whole in the effects on serum lipid levels (serum triglyceride, remnant-like particle cholesterol (RLP-C), and very-low-density lipoprotein cholesterol). However, in those subjects with high serum triglyceride levels (>130mg/dl), the serum triglyceride concentration was significantly lower after ingesting the test food than after the control food. The subjects with high serum TG levels (>220mg/dl) had a significantly lower peak serum RLP-C concentration (4h after intake) after ingesting the test food than after the control food (6.9±2.8mg/dl vs. 8.9±3.1mg/dl). To evaluate the increase in dietary lipids, we calculated the area under the time-concentration curve (AUC). This showed that RLP-C absorption from the test food was significantly slower than that from the control food (AUC=10.0±8.2mg/dl.h-1 vs. 19.5±10.1mg/dl.h-1). These results suggest that plant sterol-containing oil would be useful for reducing the cholesterol levels in a hypercholesterolemic subject.
Latent obesity (L-obesity), which is defined as BMI<25 with a body fat percentage (% fat) ≥30%, has been the recent object of intensive study. However, the nature and cause of L-obesity are unclear: We first determined the prevalence of obesity by focusing on L-obesity among two groups of female college undergraduates studying similar courses in a large city (Tokyo) and in a small prefecture (Shimane), respectively groups T and S. We then used the data to identify the anthropometric and biochemical characteristics of L-obesity. Eight anthropometric measurements were collected, including BMI, % fat and mid-upper arm circumference (MAC), together with 9 biochemical measurements, including cholinesterase, free fatty acids (FFA), fasting immuno-reactive insulin and insulin resistance. The prevalence of L-obesity was found to be significantly higher in group S (21.1%) than in group T (4.3%). The values of % fat, MAC and triceps skinfold-thickness were significantly higher in group S, while the insulin resistance was significantly higher in group T. The results show that the prevalence of L-obesity and the insulin resistance both had regional differences between the two groups of healthy young females undertaking similar study.
To investigate how to prevent osteoporosis which progresses with aging, 147 female college students (19.7± 0.9 years average age) were measured for bone density and surveyed for their past (grammar and high school period) and present daily physical activities and dietary habits. Positive correlations were found between the level of past physical activities and the lower limb bone density and between past good dietary habits and the bone density values for the trunk, pelvis and upper limbs. No significant correlation was found between the bone density and the present physical activities and dietary habits. The physical activities and good dietary habits during the grammar and high school period are suggested to have an effect on preventing osteoporosis by promoting greater peak bone mass.