Moderate egg intake, which is about one egg per day in most people, does not increase the risk of cardiovascular disease or mortality even if people have a history of cardiovascular disease or diabetes, found a Canadian analysis of three large, long-term multinational studies.
The researcher were from the Population Health Research Institute (PHRI) of McMaster University and Hamilton Health Sciences.
The results suggest there is no harm from consuming eggs. Given that the majority of individuals in the study consumed one or fewer eggs per day, it would be safe to consume this level, says Mahshid Dehghan, first author and a PHRI investigator. “Moderate egg intake, which is about one egg per day in most people, does not increase the risk of cardiovascular disease or mortality even if people have a history of cardiovascular disease or diabetes,” she said.
“Also, no association was found between egg intake and blood cholesterol, its components or other risk factors. These results are robust and widely applicable to both healthy individuals and those with vascular disease.”
Although eggs are an inexpensive source of essential nutrients, some guidelines have recommended limiting consumption to fewer than three eggs a week due to concerns they increase the risk of cardiovascular disease.
Previous studies on egg consumption and diseases have been contradictory, said Salim Yusuf, principal investigator of the study and director of PHRI. “This is because most of these studies were relatively small or moderate in size and did not include individuals from a large number of countries,” he said.
The researchers analysed three international studies conducted by the PHRI. Egg consumption of 146,011 individuals from 21 countries was recorded in the PURE study and in 31,544 patients with vascular disease from the ONTARGET and the TRANSEND studies.
The data from these three studies involved populations from 50 countries spanning six continents at different income levels, so the results are widely applicable, said Yusuf.
Background: Eggs are a rich source of essential nutrients, but they are also a source of dietary cholesterol. Therefore, some guidelines recommend limiting egg consumption. However, there is contradictory evidence on the impact of eggs on diseases, largely based on studies conducted in high-income countries.
Objectives: Our aim was to assess the association of egg consumption with blood lipids, cardiovascular disease (CVD), and mortality in large global studies involving populations from low-, middle-, and high-income countries.
Methods: We studied 146,011 individuals from 21 countries in the Prospective Urban Rural Epidemiology (PURE) study. Egg consumption was recorded using country-specific validated FFQs. We also studied 31,544 patients with vascular disease in 2 multinational prospective studies: ONTARGET (Ongoing Telmisartan Alone and in Combination with Ramipril Global End Point Trial) and TRANSCEND (Telmisartan Randomized Assessment Study in ACEI Intolerant Subjects with Cardiovascular Disease). We calculated HRs using multivariable Cox frailty models with random intercepts to account for clustering by study center separately within each study.
Results: In the PURE study, we recorded 14,700 composite events (8932 deaths and 8477 CVD events). In the PURE study, after excluding those with history of CVD, higher intake of egg (≥7 egg/wk compared with <1 egg/wk intake) was not significantly associated with blood lipids, composite outcome (HR: 0.96; 95% CI: 0.89, 1.04; P-trend = 0.74), total mortality (HR: 1.04; 95% CI: 0.94, 1.15; P-trend = 0.38), or major CVD (HR: 0.92; 95% CI: 0.83, 1.01; P-trend = 0.20). Similar results were observed in ONTARGET/TRANSCEND studies for composite outcome (HR 0.97; 95% CI: 0.76, 1.25; P-trend = 0.09), total mortality (HR: 0.88; 95% CI: 0.62, 1.24; P-trend = 0.55), and major CVD (HR: 0.97; 95% CI: 0.73, 1.29; P-trend = 0.12).
Conclusions: In 3 large international prospective studies including ∼177,000 individuals, 12,701 deaths, and 13,658 CVD events from 50 countries in 6 continents, we did not find significant associations between egg intake and blood lipids, mortality, or major CVD events.
Mahshid Dehghan, Andrew Mente, Sumathy Rangarajan, Viswanathan Mohan, Scott Lear, Sumathi Swaminathan, Andreas Wielgosz, Pamela Seron, Alvaro Avezum, Patricio Lopez-Jaramillo, Ginette Turbide, Jephat Chifamba, Khalid F AlHabib, Noushin Mohammadifard, Andrzej Szuba, Rasha Khatib, Yuksel Altuntas, Xiaoyun Liu, Romaina Iqbal, Annika Rosengren, Rita Yusuf, Marius Smuts, AfzalHussein Yusufali, Ning Li, Rafael Diaz, Khalid Yusoff, Manmeet Kaur, Biju Soman, Noorhassim Ismail, Rajeev Gupta, Antonio Dans, Patrick Sheridan, Koon Teo, Sonia S Anand, Salim Yusuf