Egg consumption and risks of all-cause and cause-specific mortality: a dose-response meta-analysis of prospective cohort studies

Context Current dietary guidelines recommend eggs as a part of a healthy diet. However, whether egg consumption is associated with risk of mortality remains controversial. Moreover, the dose-response association of egg consumption with risk of mortality has not been determined. Objective To determine the potential dose-response association of egg consumption with risk of mortality in the general population. Data Sources The PubMed and Embase databases were searched for publications meeting eligibility criteria through November 2021. Data Extraction Required data were extracted by 1 reviewer and then checked for accuracy by another reviewer. A random-effects dose-response meta-regression model was used to calculate the pooled risk estimates. A restricted cubic spline model was used to test nonlinearity. The certainty of evidence was assessed using the GRADE system. Data Analysis Nineteen prospective cohort studies, involving 1 737 893 participants, were included. The pooled hazard ratios for an increase of 1 egg/d were 1.08 (95%CI, 1.01-1.15) for all-cause mortality, 1.07 (95%CI, 0.97-1.18) for cardiovascular disease-caused mortality, and 1.16 (95%CI, 1.04-1.30) for cancer-caused mortality. The certainty of evidence for these observations was rated as very low. Nonlinear dose-response associations were found for egg consumption and all-cause, cardiovascular disease-caused, and cancer-caused mortality. Moreover, the positive association between egg consumption and all-cause mortality was more pronounced in studies with adjustment for blood cholesterol-related covariates than those without (P-interaction = 0.011). Conclusions Greater amount of egg consumption confers higher risks of death from all causes, cardiovascular disease, and canc er in a nonlinear dose-response pattern. These findings should be treated with caution and need to be confirmed by future studies.