Controlled Trial of a Diet High in Unsaturated Fat for Prevention of Atherosclerotic Complications

Thematic review series: The Pathogenesis of Atherosclerosis. An interpretive history of the cholesterol controversy: part II:the early evidence linking hypercholesterolemia to coronary disease in humans

“…They take almost all their meals in one of two dining halls on the premises. In the late 1950s, Seymour Dayton, Morton L. Pearce, and their coworkers saw this as an ideal setting for a test of the effects of unsaturated fat on atherosclerosis (43). All the men in the study were assigned to dining hall A or dining hall B.…”

“…By 1972, the importance of diet in determining serum cholesterol levels was well established, and the results of several dietary intervention trials were available. Three studies in particular-the Leren Oslo Study (42), the Wadsworth Veterans Administration Study (43), and the Finnish Mental Hospital Study (44,45)-showed that diets rich in polyunsaturated fat could significantly lower serum cholesterol levels, and collectively provided very strong evidence for the lipid hypothesis, as pointed out in a recent historical perspective by Grundy (46). Before reviewing the data from these and other dietary intervention trials, it is instructive to reexamine the scientific basis for dietary treatment of hypercholesterolemia.…”

“…This is true across a wide spectrum of blood cholesterol levels and holds on comparison of populations from different countries (37) and also within populations (40, 41), 4 ) Blood cholesterol level is increased when dietary saturated fat intake is increased, as shown by carefully controlled metabolic ward studies (49,50). Moreover, populations with dietary habits that include a high saturated fat intake have higher blood cholesterol levels and a higher CHD incidence than populations with lower saturated fat intake (37), 5 ) The wide differences in blood cholesterol levels and CHD risk between populations of different countries are due largely to environmental factors (probably diet) rather than genetic factors, as shown, for example, by the Japanese migration studies (39), 6 ) Dietary intervention to lower blood cholesterol by decreasing saturated fat intake in favor of polyunsaturated fat intake reduces blood cholesterol levels and decreases risk of CHD and other atherosclerotic complications (42)(43)(44)(45)(62)(63)(64)(65)(66)(67)(68)(69)(70). 7 ) We should be treating hypercholesterolemia.…”

Effects of hyperlipoproteinemias and their treatment on the peripheral circulation

“…5 D). 9 ±22.9 mg/100 ml (P < 0.02). In two patients whose lipids were lowered over a period of 21 days, the whole blood viscosity measured at 370C at a shear rate of 1600 sec' fell from 6.97 and 6.11 to 4.28 and 4.90 centipoise respectively, whereas the PRHBF rose from 19.5 and 16.1 ml/min per 100 g to 22.6 and 19.1 ml/100 g respectively.…”

“…Over the next 120 days, blood viscosity decreased only an additional 4.6% whereas the PRHBF increased 57%, indicating that the observed changes seen in the INTRODUCTION Whereas it is generally accepted that subjects with hyperlipidemia have an increased risk of premature coronary artery disease (1)(2)(3)(4)(5)(6), it is unclear whether efforts designed to lower serum lipids will arrest or reverse the course of the atherosclerotic process. Since population studies have thus far yielded equivocal results (7)(8)(9), it was considered desirable to examine the response of a specific vascular bed to treatment designed to lower blood lipids. In view of the difficulties inherent in measuring serial changes in the coronary circulation, it was our plan to study the vasculature of the extremities, in which the functional evaluation is simple, atraumatic, and accurate (10)(11)(12)(13)(14).…”