Preprandial and postprandial serum lipids after meals of saturated or unsaturated fat were measured in 44 men, and blood sludging in 20 men, half of whom showed a behavior pattern (A) associated with proneness to clinical coronary artery disease. The average plasma cholesterol and both fasting and postprandial triglyceride values were higher (P<0.001) in men showing pattern A, regardless of whether a saturated or unsaturated fat was given. Seven of ten men with pattern A showed severe sludging after a meal of saturated fat, five of these seven also showed sludging after a meal of unsaturated fat. Sludging was virtually absent in the noncoronary-prone group. It was concluded that substitution of an unsaturated fat for a saturated fat carries no benefit under the circumstances tested.
Friedman M, Byers SO, Rosenman RH. Effect of Unsaturated Fats Upon Lipemia and Conjunctival CirculationA Study of Coronary-Prone (Pattern A) Men. JAMA. 1965;193(11):882–886. doi:10.1001/jama.1965.03090110020005