One Chinese study even found that having an egg a day might lower the risk of heart attacks and strokes, according to the American Heart Association (AHA).
The egg yolk is full of cholesterol. However, compared with previously published analyses, the new report "is far more comprehensive, with enough data to make a strong statement that eggs and overall dietary cholesterol intake remain important in affecting the risk of [cardiovascular disease], and more so the risk of all-cause mortality", he wrote.
Dr. Terrence Sacchi, chief of cardiology at New York-Presbyterian Brooklyn Methodist Hospital in New York City and was not involved in the research, said this study is a "wake-up call not to overdo high-cholesterol foods". On average, participants were followed for about 17 years. Over the follow-up period, a total of 5,400 cardiovascular events occurred, including 1,302 fatal and nonfatal strokes, 1,897 incidents of fatal and nonfatal heart failure and 113 other heart disease deaths.
It was discovered eating an additional 300mg of dietary cholesterol per day was associated with a 3.2 per cent higher risk of cardio vascular disease and a 4.4 per cent higher risk of early death.
"Our study showed if two people had exact same diet and the only difference in diet was eggs, then you could directly measure the effect of the egg consumption on heart disease", Allen said.
The findings could be worrying for the average American, who eats between three to four eggs per week, according to the study.
Scrambled, poached or over easy: No matter how you take your eggs, there's not really a sunny side to a new study that links egg consumption with a higher risk of cardiovascular disease.
The researchers said their study looked at almost 30,000 racially and ethnically diverse United States adults from six separate studies with as much as 31 years of followup. "So I'd hate for them to come back to me and say, 'Oh, no!"
"It's a very large study with a very large number of different types of patients. They are not free from industry bias", she said. That's because unlike a randomized controlled trial that tests the safety and efficacy of a drug, it's hard to randomly control what people eat over a long period of time, especially with a large sample size.
"A more appropriate recommendation would be eating egg whites instead of whole eggs or eating whole eggs in moderation, for the objective of reducing risk of cardiovascular disease and death", he said.
But the Northwestern researchers said their study suggests those guidelines may have to be looked at yet again.
"We have one snapshot of what their eating pattern looked like", Allen said.
It's important to note that no one, including the study authors, is saying you need to cut eggs completely out of your diet.
"We want to remind people there is cholesterol in eggs, specifically yolks, and this has a harmful effect", added Allen.
Still, the findings don't mean that you have to shun eggs all together.
She recommends sticking to a Mediterranean diet, which is rich in heart-healthy plant-based foods that are also low in cholesterol, including fruits and vegetables, whole grains, legumes and nuts. "This is the diet we should be adopting".