Cancel the cheese omelette. The new smells for egg lovers who happily swallow their favorite breakfast since the 2015-2020 dietary recommendations for Americans no longer limit the amount of dietary cholesterol or the number of eggs that they can eat.
A new and large recent study from Northwestern Medicine indicates that adults consuming more eggs and dietary cholesterol had a significantly higher risk of cardiovascular disease and death, regardless of the cause.
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"The takeaway really concerns cholesterol, which contains eggs and especially yellows," said author of the co-corresponding study, Norrina Allen, associate professor of preventive medicine at Feinberg School. of Medicine at Northwestern University. "As part of a healthy diet, people need to consume less cholesterol. People who consume less cholesterol have a lower risk of heart disease. "
Egg yolks are one of the richest sources of dietary cholesterol among all commonly eaten foods. A large egg contains 186 milligrams of dietary cholesterol in the yolk.
Other animal products such as red meat, processed meat and high-fat dairy products (butter or whipped cream) also have a high cholesterol content, said the author Senior Wenze Zhong, Postdoctoral Fellow in Preventive Medicine at Northwestern.
Debate on the disease
Whether cholesterol or egg consumption is linked to cardiovascular disease, death has been the subject of debate for decades. The recommendation before 2015 was to recommend eating less than 300 milligrams of dietary cholesterol per day. However, the latest dietary recommendations omitted a daily limit for dietary cholesterol. The guidelines also include weekly egg consumption as part of a healthy diet.
In the United States, an adult consumes on average 300 milligrams of cholesterol per day and eats about three or four eggs a week.
The results of the study mean that the recommendations of the current US Food Guidelines for dietary cholesterol and eggs may need to be re-evaluated, the authors said.
Evidence for the eggs has been mixed. Previous studies have shown that eating eggs does not increase the risk of cardiovascular disease. But these studies generally had a less diverse sample, shorter follow-up time, and limited ability to adapt to other parts of the diet, Allen said.
"Our study showed that if two people followed exactly the same diet and that the only difference in their diet was eggs, you can then measure directly the effect of egg consumption on heart disease," said Allen. "We found that cholesterol, regardless of its source, was associated with an increased risk of heart disease.
Exercise, the overall quality of the diet, the amount and type of fat in the diet have not changed the link between dietary cholesterol and cardiovascular disease and the risk of death.
The new study examined data collected from 29,615 American adults of various racial and ethnic origins from six prospective cohort studies over a period of up to 31 years.
- Consumption of 300 mg of dietary cholesterol per day was associated with a higher risk of incident cardiovascular disease by 17% and a higher risk of all-cause death. Cholesterol was the independent determinant of the intake of saturated fats and other dietary fats.
- Consumption of three to four eggs per week was associated with a 6% higher risk of cardiovascular disease and a risk of all-cause mortality of 8%.
Should I stop eating eggs?
According to this study, people should limit their dietary cholesterol intake by cutting down high-cholesterol foods such as eggs and red meat.
But do not completely ban eggs and other high-cholesterol foods from meals, Zhong said, because eggs and red meat are good sources of essential nutrients such as essential amino acids, iron and choline. Instead, choose egg whites rather than whole eggs or eat whole eggs in moderation.
"We want to remind people that cholesterol in eggs, especially yolks, has a detrimental effect," said Allen, who made scrambled eggs for his kids that morning. "Eat them in moderation."
Estimate of food intake
Food data were collected using food frequency questionnaires or taking the food history. Each participant was asked a long list of what they ate during the year or the previous month. The data was collected during a single visit. The study had a follow-up of up to 31 years (median: 17.5 years), during which 5,400 cardiovascular events and 6,132 deaths from all causes were diagnosed.
One of the main limitations of the study is that participants' long-term dietary habits have not been evaluated.
"We have an overview of their eating habits," Allen said. "But we think they represent an estimate of a person's dietary intake. Yet people may have changed their diet and we can not account for it. "
Other Northwestern writers include Linda Van Horn, Marilyn Cornelis, John Wilkins, Hongyan Ning, Mercedes Carnethon, Philip Greenland, Lihui Zhao and Donald Lloyd-Jones.