Meta-analysis of Egg Consumption and Risk of Coronary Heart Disease and Stroke

Abstract

The possible relationship between dietary cholesterol and cardiac outcomes has been scrutinized for decades. However, recent reviews of the literature have suggested that dietary cholesterol is not a nutrient of concern. Thus, we conducted a meta-analysis of egg intake (a significant contributor to dietary cholesterol) and risk of coronary heart disease (CHD) and stroke. A comprehensive literature search was conducted through August 2015 to identify prospective cohort studies that reported risk estimates for egg consumption in association with CHD or stroke. Random-effects meta-analysis was used to generate summary relative risk estimates (SRREs) for high vs low intake and stratified intake dose-response analyses. Heterogeneity was examined in subgroups where sensitivity and meta regression analyses were conducted based on increasing egg intake. A 12% decreased risk (SRRE = 0.88, 95% confidence interval [CI], 0.81-0.97) of stroke was observed in the meta-analysis of 7 studies of egg intake (high vs low; generally 1/d vs <2/wk), with little heterogeneity (p-H = 0.37, I = 7.50). A nonstatistically significant SRRE of 0.97 (95% CI, 0.88-1.07, p-H = 0.67, I = 0.00) was observed in the meta-analysis of 7 studies of egg consumption and CHD. No clear dose-response trends were apparent in the stratified intake meta-analyses or the meta regression analyses. Based on the results of this meta-analysis, consumption of up to one egg daily may contribute to a decreased risk of total stroke, and daily egg intake does not appear to be associated with risk of CHD. Key Teaching Points: • The role of egg consumption in the risk of stroke and coronary heart disease has come under scrutiny over many years. • A comprehensive meta-analysis of prospective cohort studies that reported risk estimates for egg consumption in association with CHD or stroke was performed on the peer-reviewed epidemiologic literature through August 2015. • Overall, summary associations indicate that intake of up to 1 egg daily may be associated with reduced risk of total stroke. • Overall, summary associations show no clear association between egg intake and increased or decreased risk of CHD. • Eggs are a relatively low-cost and nutrient-dense whole food that provides a valuable source of protein, essential fatty acids, antioxidants, choline, vitamins, and minerals.

Regarding associations of egg consumption with cardiovascular disease in a cohort study of 0.5 million Chinese adults

“…In our study, participants who had the lowest risk of CVD consumed an average of 0.76 egg daily, lower than the highest level in the Western and Japanese population 3. But this average level was close to the amount (40 – 50  g   per day) recommended by the Chinese Dietary Guideline 4.…”

The Impact of Egg Nutrient Composition and Its Consumption on Cholesterol Homeostasis

“…Therefore, people tend to limit their consumption of eggs to decrease the cholesterol intake, in order to protect themselves from CVD. However, the controversy does not stop here, later studies do not support this hypothesis, and potential beneficial effects of egg on CVD have been reported [12–23, 150, 151, 185]. A prospective study with over 117,000 adults and 14-year follow-up demonstrated that there were no differences of CVD risks between participants that consumed one egg per week and those who consumed one egg per day [12].…”

“…The effects of egg intake on blood cholesterol and CVD have been discussed in several meta-analysis studies using research data collected over 60 years [15, 21–23, 180, 194]. Large epidemiological works have been conducted to investigate the effect of egg intake on blood cholesterol levels and risk of CVD in children [123], young people [16, 20, 47, 124], women [12–14, 125, 195, 196], men [12–14, 125, 195–199], and older adults [12–14, 125, 195–200].…”

“…Shekelle (1989) and Kushi (1985) found dietary cholesterol was correlated to CVD risks, but they failed to take many confounding variables into account, such as genes, hormones, other dietary components, lifestyle, and the nutritional status of the subjects [6, 7]. On the other hand, later epidemiological studies and systematic reviews reported a marginal correlation between dietary cholesterol and/or egg intake and CVD incidence in the general population [12–23]. With increasing evidences of weak correlation, AHA eliminated the restriction of egg consumption in 2002 and the dietary restriction of cholesterol for healthy population in 2013 [24].…”

Papel del huevo en la dieta de deportistas y personas físicamente activas

“…Sin embargo, cada vez hay más evidencias de que el consumo de huevo tiene poca o nula influencia sobre los niveles de colesterol sérico, mientras que puede incluso ser beneficioso desde el punto cardiovascular. Recientes estudios concluyen que el consumo de huevo no se asocia a un mayor riesgo de enfermedad coronaria (13,14), y no supone un mayor riesgo de ictus (13) e incluso puede ser un factor protector (14).…”