The large, long-running study - published today (March 15) in the journal JAMA - found that eating three to four eggs per week was linked to a 6 percent increase in a person's risk of developing heart disease and an 8 percent increase in their risk of dying from any cause during the study period, compared with not eating eggs.
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.
Hold that three-egg omelet.
This news might be hard to swallow for some egg lovers, considering the fact that the 2015-2020 Dietary Guidelines for Americans actually encourages the consumption of eggs as part of a healthy eating pattern. One large egg contains about 186 milligrams of dietary cholesterol in the yolk. "As part of a healthy diet, people need to consume lower amounts of cholesterol".
Eggs are a leading source of dietary cholesterol, which once was thought to be strongly related to blood cholesterol levels and heart disease. 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).
Researchers in the Northwestern study found that eating 300 milligrams of cholesterol per day was associated with a 17 percent higher risk of heart disease and an 18 percent higher risk of all-cause deaths.
Cho says she never stopped recommending her patients limit their dietary cholesterol intake to 300 milligrams a day or told patients they could eat as many eggs as they want.
"There's always been a [suggestion in the data] that eggs can raise cholesterol and create cardiovascular harm", said Dr. Andrew Freeman, director of the Cardiovascular Prevention and Wellness program at National Jewish Health hospital in Denver.
The latest USA government nutrition guidelines, from 2015, removed the strict daily cholesterol limit.
Freeman cited concerns about the influence of the agricultural and food industry over the guidelines as a reason for this contradiction, and the general downplaying of the link between dietary cholesterol and heart disease. Participants were followed for an average of 17.5 years.
US dietary guidelines that eased limits on cholesterol have helped eggs make a comeback. 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.
The researchers based their conclusions on what participants said they ate at the start of each study.
Wait a second, eggs are bad again? Of course, cheeseburgers have many other dietary problems, including saturated fat and sodium.
"The old advice still stands, eggs in moderation are absolutely fine as a useful source of protein".
"A more appropriate recommendation would be eating egg whites instead of whole eggs or eating whole eggs in moderation, for the goal of reducing risk of cardiovascular disease and death", he said. "For example, poached eggs on whole-grain toast is a much healthier meal than a traditional fry up".