The latest American egg research will not be easy for those who cannot do without.
Adults who ate about 1 and a half eggs a day had a slightly higher risk of heart disease than those who did not eat eggs. The study showed that the more eggs, the greater the risk. The chances of dying early were also high.
Researchers say the culprit is cholesterol, which is found in egg yolks and other foods, including seafood, dairy products, and red meat. The study focused on eggs because they are among the most rich in cholesterol that are consumed the most. Researchers can still be part of a healthy diet, but in smaller amounts than many Americans are used to.
The nutritional guidelines of the US. UU. who have facilitated cholesterol limits have helped restore eggs.
The research has limitations and contradicts recent research, but it is likely to resume the long debate about eggs.
The new results were published online Friday in the Journal of the American Medical Association.
Researchers from the Feinberg School of Medicine at Northwestern University and elsewhere collected the results of six previous studies, analyzing data from nearly 30,000 adults in the United States. UU. The participants were followed on average for around 17 years.
The researchers calculated that those who ate 300 milligrams of cholesterol a day, about one and a half eggs, were 17 percent more likely to develop heart disease than those who did not eat eggs.
The researchers based their conclusions on what the participants said they ate at the start of each study. They took into account high blood pressure, smoking, obesity and other characteristics that can contribute to heart problems. There were risks with eggs and cholesterol in general; no separate analysis was performed for each high cholesterol food.
Dr. Bruce Lee of Johns Hopkins University said that nutrition studies are often weak because they depend on people who remember what they ate.
"We know that the memory of the diet can be terrible," Lee said. The new study only provides observation data, but does not show that eggs and cholesterol have caused heart disease and death, said Lee, who was not involved in the study.
The lead author, Norrina Allen, a specialist in preventive medicine, said the study lacks information about whether the participants ate boiled, poached, deep-fried or scrambled eggs in butter, which she thought could affect health risks.
Some people think "I can eat as many eggs as I want," but the results suggest that moderation is a better approach, he said.
Eggs are an important source of cholesterol in the diet, previously thought to be strongly related to blood cholesterol and heart disease. Older studies suggested that the link led for nearly ten years to dietary guidelines that recommended the use of no more than 300 milligrams of cholesterol per day; an egg contains approximately 186 milligrams.
More recent research questioned that relationship and discovered that saturated fats contribute more to unhealthy blood cholesterol levels that can cause heart problems.
The latest nutritional guidelines from the US government UU., 2015, eliminated the strict daily cholesterol limit. Although it is still recommended to eat as little cholesterol as possible, the recommendations indicate that eggs can still be part of a healthy diet, as a good source of protein, along with lean meats, chicken, beans, and nuts. Nutritionists say the new study is unlikely to change this advice.
Dr. Frank Hu from Harvard University pointed out that most previous studies have shown that eating a few eggs a week is not related to the risk of heart disease in generally healthy people.
"I don't think this study changes the general guidelines for healthy eating," which emphasizes fruits, vegetables, whole grains, nuts, and beans and limits processed meat and sugar, Hu said.
Eggs, a simple breakfast for many, can be included, but other options should also be considered, "such as whole-wheat toast with nut butter, fresh fruit, and yogurt," Hu said.
Dr. Rosalind Coleman, professor of nutrition and pediatrics at the University of North Carolina, gave broader advice.
"The most important message for the public is not to select a type of food as" bad "or" good ", but to evaluate the overall diet in terms of variety and quantity.
"I'm sorry if it seems like a boring recommendation," he added, but for most people the most important nutritional advice should be: maintain a healthy weight, exercise and get enough sleep. "