Saturated fatty acids and CHD

Notwithstanding the fact that the consumption of certain saturated fatty acids can increase plasma cholesterol level, which is a risk factor for CHD, is there any direct evidence to indicate that saturated fatty acids are associated with the risk of CHD  

Most ecological studies showed a strong positive correlation between per capitut disappearance rates of dietary fat, dairy fat, saturated fat, or 

Only a few case-control studies have investigated the association between CHD and the intake of saturated fat, polyunsaturated fat or total fat by CHD patients and by subjects free from CHD. Ravnskov (1998) lists six studies, none of which supported the hypothesis that saturated fat is associated with an increased risk, and polyunsaturated fat with a decreased risk of CHD. 

Ravnskov (1998) presented data for 28 cohorts from 21 prospective studies. In only three of these cohorts did the evidence show that saturated fat was associated with a statistically significant increased risk of CHD. CHD patients in three cohort studies had consumed significantly more polyunsaturated fat, and in only one cohort had CHD patients eaten less polyunsaturated fat than CHD-free participants. The cohorts included the Framingham Study and the large well-conducted Health Professionals Follow-up Study and the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study. Since then, Hu et al. (1997) presented the 14-year follow-up data from the Nurses Health Study. After adjustment for confounding variables in multivariate analyses, no statistically significant associations were found between intake of total fat, animal fat, or saturated fat and the risk of CHD. 

Epidemiological studies provide little, if any, evidence to support the hypothesis that saturated fatty acids, even those of chain length Ci2 o - Ci6 o that can elevate serum cholesterol concentration, are associated with the risk of CHD. This may result from the increased plasma HDL-cholesterol concentration produced by saturated fatty acids largely compensating for the adverse effects of these fatty acids on LDL-cholesterol concentration (Hu and Willett, 2000). In addition, saturated fatty acids lower the level of plasma Lp[a], which is considered a significant risk factor for CHD (Mensink et al., 1992). 

---