Association of Egg Consumption with Risk of All-Cause and Cardiovascular Disease Mortality: A Systematic Review and Dose-Response Meta-Analysis of Observational Studies

Background Recent studies have reported conflicting associations between egg consumption and the risk of all-cause or cardiovascular disease (CVD) mortality, including ischemic heart disease (IHD) mortality and stroke mortality. With accumulating evidence, up-to-date evidence about the association should be synthesized. Objectives We aimed to assess the association of the risk of all-cause and CVD mortality with egg consumption. Methods We searched the PubMed, Embase, and Web of Science databases through 3 November, 2021 for observational studies conducted in participants >= 18 y of age and which provided ORs, RRs, or HRs and 95% CIs for >= 3 egg consumption categories or for increased intake of egg addressing the associations of interest. A random-effects model was used to pool the reported risk estimates. Restricted cubic splines were used to examine the dose-response association. Results Twenty-four articles with 48 reports (25 for all-cause mortality, 11 for CVD mortality, 6 for IHD mortality, and 6 for stroke mortality) involving 11,890,695 participants were included. Intake of each 1-egg/d increment was associated with increased risk of all-cause mortality (RR: 1.06; 95% CI: 1.02, 1.10; P = 0.008), but the association was restricted to women, Americans, and studies with adjustments for hyperlipidemia. Egg consumption was linearly associated with CVD mortality only in participants >60 y of age, Americans, studies with follow-up duration >= 15 y, and studies with adjustments for hyperlipidemia (P <= 0.018). No significant association was found between egg consumption and IHD or stroke mortality (P >= 0.080). Conclusions Egg consumption was linearly associated with a modestly increased risk of all-cause mortality and, in older participants, Americans, and studies with longer follow-up or adjustments for hyperlipidemia, CVD mortality. These findings suggest that it may be prudent to avoid high egg consumption.