>Accumulated epidemiologic evidence generated from this meta-analysis suggests that egg consumption is not associated with an increased risk of overall CVD, IHD, stroke, or mortality. However, compared with those who never consume eggs, those who eat 1 egg per day or more are 42% more likely to develop type 2 diabetes. Among diabetic patients, frequent egg consumers (ie, ≥ 1 egg/d) are 69% more likely to have CVD comorbidity.

>In the current meta-analysis, we observed a positive association between egg consumption and risk of type 2 diabetes. Although the findings were inconsistent, some animal studies suggested that high cholesterol feeding increased fasting plasma glucose concentrations or induced hyperinsulinemia and impaired glucose tolerance (61–63). Studies have also suggested that elevated serum cholesterol might be associated with an increased islet cholesterol content and directly induce β cell dysfunction by reducing glucose-stimulated insulin secretion (64, 65). In addition, studies have indicated that dietary cholesterol might be associated with chronic, low-grade inflammation (66, 67), which is a mechanism underlying the development of insulin resistance and type 2 diabetes. Moreover, our results on egg consumption and risk of diabetes are supported by some other human studies (38–40, 68) that do not meet our inclusion criteria... Of note, the possibility cannot be completely excluded that the observed positive associations between egg consumption and risk of type 2 diabetes are explained by residual confounding from unmeasured factors, because diabetes was the secondary outcome in most included studies. Nevertheless, future studies are warranted.