Evaluation of the effects of freeze-dried soybean curd intake on cholesterol levels using a novel biomarker.

To evaluate the effects of freeze-dried soybean curd intake on serum cholesterol levels, we examined the subclasses of cholesterol for healthy adult volunteers who continued to eat a piece of freeze-dried soybean curd each day along with their ordinary diet for four weeks. Of 12 subjects, the soybean curd diet proved effective in 2 cases; small dense LDL (sd-LDL) cholesterol levels were significantly reduced in association with the decrease in LDL cholesterol levels. These results suggested that daily intake of freeze-dried soybean curd may lead to an improvement in cholesterol metabolism in subjects with originally higher cholesterol levels and that sd-LDL cholesterol can be a novel biomarker for evaluation of the cholesterol lowering-action of functional food.