The results of this study showed that egg consumption did not unfavorably influence serum cholesterol or other measurement of the lipid profile, in a previously noninvestigated population of hyperlipidemic adults who were treated with lipid-lowering drugs. In addition, egg consumption led to an increase in HDL-C as well as a decrease in LDL-C to HDL-C ratio, the major determinants of CVD risk.
The other cohort study that has specifically examined the relationship between egg consumption and CVD included 37,851 men and 80,002 women who were free from chronic diseases of the Health Professionals Follow-Up Study and the Nurses' Health Study. After adjusting for multiple confounders, those eating >7 eggs/week (as compared with those consuming <1 egg/week) had no increased risk of CVD or stroke in either healthy men or women [11
]. In two other cohorts, eating eggs more frequently was not associated with an increase in stroke or CVD incidence [4
Clinical trials conducted in healthy postmenopausal women and men aged 60 years or older have clearly demonstrated that women and men classified as hyporesponders to dietary cholesterol had no changes in LDL-C and HDL-C after consuming 3 eggs per day for 4 and 12 weeks, respectively. In contrast, those individuals who were classified as hyperresponder exhibit increases in both LDL-C and HDL-C with the result of no changes in the LDL-C to HDL-C ratio [13
]. In hyperlipidemic adults, 2 eggs consumption daily for 6 weeks had no adverse effect on endothelial function and serum cholesterol or other measures of the lipid profiles compared to sausage and cheese consumption [10
The lipid profile after consuming additional 3 eggs per day in hyperlipidemic adults, who were treated with lipid-lowering drugs, changed similar to those of hypo-responders: no change in LDL-C, increase in HDL-C, and decrease in LDL-C to HDL-C ratio. These findings in keeping with a previous study of the effect of egg consumption in patients on HMG-CoA reductase inhibitor showed significant increases in HDL-C in subjects given 2 or 4 eggs daily [15
]. The absence of an increase in plasma cholesterol in hyporesponders may be explained by their ability to maintain cholesterol homeostasis by decreasing the absorption of dietary cholesterol or suppressing endogenous synthesis [13
]. Lipid-lowering drug in our study is HMG-CoA reductase inhibitor which can inhibit endogenous cholesterol synthesis like hypo-responders [16
]. Increasing in HDL-C level by 1
mg/dL may reduce the risk of CVD by 2 to 3 percent [17
], and decreasing in LDL-C to HDL-C ratio by 1 unit may decrease the risk of myocardial infarction by 50 percent [18
]. Moreover, daily intake of 3 eggs significantly increases adiponectin that is both anti-inflammatory and antiatherogenic hormone [19
]. In this study, HDL-C significantly increased while LDL-C to HDL-C ratio significantly decreased after egg consumption which may provide protection against development of CVD. Egg consumption failed to show the association to LDL-C and TC, but egg consumption showed the results with parameters to reduce risk of CVD.