Plant Sterols, Degree of Unsaturation, and Hypocholesterolemic Action of Certain Fats

Abstract

Dietary experiments in which food was supplied in the form of a homogeneous liquid formula ration of definitely known composition have been performed on 171 subjects (159 men and 12 women, university students).During an initial period of 8 days all subjects ate the same ration and then groups of 8 to 12 individuals were given rations varying in respect of the fat moiety for a further 8 days. Plasma cholesterol analyses were performed at day 0, 4, 8, 12, and 16.The results obtained were interpreted as indicating that: firstly, there is no simple relationship between the hypocholesterolemic effect of an oil and degree of unsaturation; secondly, sitosterol or something closely associated with this sterol in the unsaponifiable matter accounts for a large part of the hypocholesterolemic activity of corn oil; and thirdly, certain fatty acids of short chain length or some other substance in butterfat and coconut oil have a hypercholesterolemic effect.

The Effect of Partial Hydrogenation of Dietary Fats, of the Ratio of Polyunsaturated to Saturated Fatty Acids, and of Dietary Cholesterol upon Plasma Lipids in Man *

“…Results obtained in this laboratory (19), in addition to those of other investigators (20)(21)(22)(23)(24), have indicated that partial hydrogenation has little effect on the hypocholesterolemic action of dietary fats. There are,-however, numerous reports (8, 9, 13.…”

“…The reports in the literature do not agree as to whether hydrogenation of a vegetable oil alters its hypocholesterolemic action (8,9,17,20,26,38,39). Since the process of hydrogenation, as normally used in the preparation of edible fats, results in the conversion of polyunsaturated to monounsaturated fatty acids and in the formation of some isomeric unsaturated fatty acids, either one or both types of change might possibly modify the plasma cholesterol response.…”

Understanding the Complexity of Trans Fatty Acid Reduction in the American Diet

“…One year later, researchers reported that within the context of a 35% butterfat diet, there was no significant difference between supplemental corn oil and hydrogenated corn oil. 2 Between 1960 and 1990, numerous additional studies were published with inconsistent results. This variability is likely attributable to differences in the background diets, starting fatty acid profile of the test oil, differences in the degree and type of hydrogenation, and less-than-optimal comparison fats.…”

Regression Studies with Safflower Oil and Sitosterol in Rabbit Atherosclerosis

“…This paper describes experiments using these cholesterol-free diets with HCO to induce atheroma and to test their regression when the HCO was replaced by SO. In human studies, Beveridge et al 2 reported that the unusual hypocholesteremic effect of corn oil is due to its relatively high sitosterol eontent. We were interested, therefore, to test the value of both SO and SO plus /?-sitosterol (S:S) to regress atheroma in rabbits.…”