Egg, cholesterol consumption linked to higher mortality from CVD, cancer

Whole egg and cholesterol intake was associated with CVD, cancer and all-cause mortality, data from a cohort of more than a half million people showed.

For years, the effects of egg and cholesterol intake on cardiovascular health has been “highly debated,” according to Pan Zhuang, a PhD candidate at the Zhejiang Key Laboratory for Agro-Food Processing at Zhejiang University in China, and colleagues.

Previously, two prospective studies published in 2019 — one in The American Journal of Clinical Nutrition and another in The BMJ — both concluded eating one egg daily does not increase the risk for CVD.

In addition, “the most recent meta-analysis [in 2015] showed heterogeneous results about the relationship between dietary cholesterol and the risk of CVD death, coronary artery disease and stroke,” Zhuang and colleagues wrote.

Thus, according to the researchers, recommendations from the American Heart Association and American College of Cardiology on reducing CVD risk (2013) and blood cholesterol management (2018) and the United States 2015–2020 dietary guideline did not include previous recommendations regarding upper limit for dietary cholesterol.

In the new study, the researchers analyzed data from the NIH-AARP Diet and Health Study. This study collected demographic, lifestyle characteristics and diet history from 521,120 United States adults (mean age = 62.2 years; 41.2% women and 91.8% non-Hispanic white) from six states and two additional cities between 1995 and 1996. Participants were prospectively followed up until the end of 2011. There were 129,328 deaths — including 38,747 deaths from CVD — during a median follow-up of 16 years.

Zhuang and colleagues reported that whole egg consumption was significantly associated with all-cause, CVD and cancer mortality. A multivariable-adjusted analysis further showed that consuming an additional half of a whole egg daily was associated with higher probability of mortality from all causes (HR = 1.07; 95% CI, 1.06-1.08), CVD (HR = 1.07; 95% CI, 1.06-1.09) and cancer (HR = 1.07; 95% CI, 1.06-1.09). Each additional 300 mg of dietary cholesterol consumed daily was associated with higher mortality from all causes (19%), CVD (16%) and cancer (24%).

Using mediation models, the researchers estimated that cholesterol consumption contributed to 63.2% (95% CI 49.6%-75%) of all-cause mortality, 62.3% (95% CI 39.5%-80.7%) of CVD mortality and 49.6% (95% CI, 31.9%-67.4%) of cancer mortality associated with whole egg consumption. Participants who ate egg whites or egg substitutes had lower all-cause mortality and lower mortality from stroke, cancer, respiratory disease and Alzheimer’s disease vs. those who did not eat these products.

“Clinicians and policymakers should continue to highlight limiting cholesterol intake in the U.S. dietary recommendations, considering our results,” Zhuang and colleagues wrote. “The U.S. dietary guidelines may recommend replacing whole eggs with egg whites/substitutes or alternative protein sources for facilitating cardiovascular health and long-term survival.”