Image : Andreas Rentz ( Getty Images ) Breakfast sandwich fans beware: Eating too many eggs might be bad for your health... again. A new study released Friday found that daily consumption of a certain amount of cholesterol, a key nutrient of eggs, is linked to a modest increase in the risk of cardiovascular disease and early death. Advertisement The findings, if valid, could overturn the current medical consensus that there’s no need to watch your cholesterol or egg intake—itself a controversial idea among nutritionists. In 2016, the United States Department of Agriculture finalized its current five-year update of the Dietary Guidelines for Americans, meant to run until 2020. There was one change from previous guidelines that got everyone’s attention. The USDA no longer called for a upper limit to the amount of dietary cholesterol you should have, which was previously set at 300 milligrams a day (one large egg alone provides around 160 milligrams). Instead, the guidelines said, dietary cholesterol shouldn’t be considered “a nutrient of concern for overconsumption.” The USDA’s decision, which did receive some criticism at the time, reflected the latest shift in thinking around cholesterol in the nutrition world. To put it simply, studies haven’t consistently shown that more cholesterol in our diets leads to more cholesterol in the blood, particularly the unhealthier low-density lipoprotein (LDL) cholesterol, which can contribute to clogged arteries and heart disease. Nor have they clearly shown that eggs and dietary cholesterol are linked to poorer health, since factors like a person’s overall diet can cloud the picture. People who love to eat eggs, for instance, might also love eating unhealthier foods like bacon in general. The authors behind this new paper, published in JAMA, acknowledge the long-standing debate around eggs’ benefits and harms. But they argue that their study’s design and methodology was able to separate the wheat from the chaff and look at the effects of cholesterol and eggs in isolation and in more detail than other attempts. “With eggs, like most foods, there are good and bad parts to them. And it’s been very hard to tease apart the potential harmful effects of high cholesterol in eggs vs other beneficial nutrients,” study author Norrina Allen, associate professor of preventive medicine at the Northwestern University Feinberg School of Medicine in Illinois, told Gizmodo. They turned to the Lifetime Risk Pooling Project, which combines data from 20 large population studies that have tracked people’s health over years to figure out risk factors for cardiovascular disease. For this study, they used data from six studies, which collectively involved nearly 30,000 relatively healthy, middle-aged people with no pre-existing heart disease and followed them for a median of 17 years and up to as long as 31 years. All of the volunteers, at the start of their respective studies, detailed their typical diet, including how much they ate eggs and other high-cholesterol foods like red meat. Advertisement Ultimately, they found there was a 17 percent increased risk of cardiovascular disease associated with every extra 300 milligrams of dietary cholesterol a day, along with an 18 percent increased risk of early death, even after adjusting for factors like the amount of calories eaten per day. And each extra half-egg a day was similarly linked to a 6 percent and 8 percent increased risk of cardiovascular disease and early death, respectively. The link between egg consumption and poorer health went away after accounting for a person’s cholesterol intake, suggesting their high cholesterol content was the principle reason behind the increased risk. The findings, Allen said, might prompt yet another reconsideration of health organizations’ advice to not worry about dietary cholesterol or eggs. Advertisement “I think [organizations like the USDA] were working with the best evidence they had available, which has never been conclusive,” she said. “But this study is a large, very strong observational study that may start to change the balance of data.” At the same time, Allen and her team caution that people shouldn’t be too worried about their egg-eating habits. For one, though the average American eats around three to four eggs a week, they’re not the only major source of cholesterol in our diet; processed and red meats provide plenty, too. And unlike some studies, this one included more of a real-world context. Advertisement The researchers estimated that the absolute risk difference linked to eating 300 milligrams of cholesterol a day, over a 31-year-period, was 3.24 percent for cardiovascular disease and 4.43 percent for mortality. In other words, if your risk of heart disease in the next 31 years was 5 percent (hypothetically), eating that much cholesterol would raise it to around 8 percent. That’s an important increase, one most of us would probably want to avoid, given the average American eats around 300 milligrams of cholesterol a day. But it’s still a small added risk in the grand scheme of things. Allen believes that this study and others like it in the future could be enough to convince the USDA and other health organizations to revise their cholesterol advice. But there are also steps they say the average person can take right now. Advertisement “We’ve known for a long time that the yolk in eggs is the main source of cholesterol found in them. So we would advocate that people reduce their cholesterol intake, and if you’re eating eggs, that maybe you just eat the egg whites and moderate your consumption of yolk,” Allen said. “Also, eggs aren’t the only thing cholesterol comes out of, so people should moderate their consumption of those foods as well.” In the future, Allen hopes she and others can establish a clear threshold of perfectly safe egg consumption, as well as whether certain individuals respond differently to dietary cholesterol.<doc-sep>Eggs are back in the news, with a new study concluding that regular consumption of the beloved breakfast food may increase the risk of heart disease after all. 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 culprit, the researchers wrote, appears to be cholesterol; the study also found that eating 300 mg of cholesterol per day was tied to a 17 percent increase in the risk of developing heart disease and an 18 percent increase in the risk of dying during the study period, compared with consuming no cholesterol. The new findings contradict the latest dietary guidelines for Americans, released in 2015; in them, the U.S. Department of Health and Human Services and the U.S. Department of Agriculture (USDA) said that Americans no longer had to worry about keeping their cholesterol intake within a certain limit. The authors of the new study, from Northwestern University Feinberg School of Medicine, conclude that Americans should limit their cholesterol and egg consumption, and that current dietary guidelines for cholesterol may need to be reevaluated. So what does this mean for the beloved breakfast food? Indeed, at 186 milligrams of cholesterol per egg yolk, eggs are one of the highest cholesterol foods typically consumed by Americans. [7 Tips for Moving Toward a More Plant-Based Diet] To find out where Americans should stand on "eggs for breakfast," Live Science reached out to several experts who weren't involved with the new research. The trouble with cholesterol "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 evidence is pretty clear that animal products, and high-cholesterol products, should be limited" in the diet, Freeman told Live Science. Although some previous studies have failed to find a link between eggs, along with other forms of cholesterol consumption, and heart disease risk, the new study was able to thoroughly adjust for other foods in a person's diet in order to focus on the effect of eggs and cholesterol. "This study does a good job of parsing the data and identifying dietary cholesterol as an individual and independent component of diet" that's linked with heart disease and mortality, said Dana Hunnes, a senior dietitian at the Ronald Reagan UCLA Medical Center in Los Angeles. The apparent back-and-forth on egg recommendations has meant that "this had become a confusing topic to discuss with patients," said Dr. Seth Martin, a cardiologist and associate professor of medicine at Johns Hopkins University School of Medicine. "It is nice to get clearer data on this controversial topic to better inform future guidelines and our patients," Martin said of the new study. Some of the confusion around cholesterol in the diet stems from two seemingly contradictory statements that appear in the 2015 dietary guidelines. On the one hand, the guidelines say that "cholesterol is not a nutrient of concern for overconsumption;" but on the other hand, the guidelines say that "individuals should eat as little dietary cholesterol as possible while consuming a healthy eating pattern." [9 Disgusting Things That the FDA Allows in Your Food] 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. Hunnes agreed. "The USDA oversees both agriculture — including [the] egg industry — and dietary guidelines. They are not free from industry bias," she said. Moderation is still important Still, the findings don't mean that you have to shun eggs all together. As with any food, "everything in moderation" remains good advice, said Dr. Satjit Bhusri, a cardiologist at Lenox Hill Hospital in New York City. Limiting cholesterol may be particularly important for people already at risk for heart disease. "Given the volume of heart disease and death from chronic diseases … in our country, I think that consuming fewer eggs on a weekly basis would behoove most people, and especially those with other [health conditions] and/or chronic diseases to start out with," Hunnes said in an email. The authors pointed out that most of the cholesterol found in eggs is in the egg yolk, so egg whites are still on the table. It's important to note that the study found only an association, and it cannot prove that eggs or cholesterol directly cause heart disease. In addition, the study assessed people's diets at a single point in time, not accounting for changes in a person's diet that may have occurred during the study period. Originally published on Live Science.<doc-sep>Are eggs good for you? The long-standing dairy discussion may have more answers, and it looks like bad news for egg lovers. A new study suggests people with a higher consumption of eggs or cholesterol may be at a higher risk for cardiovascular disease and early death. Eggs are a "major source of dietary cholesterol," the study authors say, and much debate has been had in recent years over guidelines for Americans and cholesterol consumption. In their analysis, researchers found a 17 percent increased risk of cardiovascular disease and 18 percent increased risk of premature death associated with each additional 300 milligrams of dietary cholesterol had each day. Each additional half an egg eaten each day, or three to four eggs per week was associated with a 6 percent higher risk of cardiovascular disease and an 8 percent higher risk of early death. Americans get an average of 300 milligrams of dietary cholesterol per day and eat an average of about half an egg daily, the study authors say. "The take-home message is really about cholesterol, which happens to be high in eggs and specifically yolks," study co-author Norrina Allen, a Northwestern University medicine professor, said in a statement. "As part of a healthy diet, people need to consume lower amounts of cholesterol. People who consume less cholesterol have a lower risk of heart disease." More:Eating more fiber and whole grains may mean a lower risk of death and disease, study finds More:New guidelines suggest a 'lifespan approach' to battle high cholesterol The research, published Friday in the Journal of the American Medical Association, drew on data from six studies in the Lifetime Risk Pooling Project, which included over 29,000 people followed for a median of 17.5 years of follow-up. In that follow-up time, there were 5,400 incidents of cardiovascular disease, both fatal and nonfatal. The study authors say past research wasn't conclusive on the heightened risks of cardiovascular disease associated with eggs, and the sample data some used weren't as diverse. While Allen isn't suggesting people stop eating eggs altogether, they should eat them in moderation, she said in a statement. More:Parents, watch for these warning signs of heart disease in youth More:Mediterranean is the best way to eat in 2019, according to new diet rankings The researchers also say U.S. dietary guideline recommendations may need to be re-evaluated given that there is not a recommended daily limit for dietary cholesterol. The average large egg, including its yolk, is about 50 grams and contains approximately 186 milligrams of cholesterol, the authors say. While the study may raise some concerns for egg eaters, there are limitations to the research. The study only showed an association, not a cause-and-effect relationship between eating eggs or cholesterol and their health risks. Researchers also couldn't account for longer-term changes to people's diets in the samples. Follow USA TODAY's Ryan Miller on Twitter @RyanW_Miller<doc-sep>
Credit: CC0 Public Domain Cancel the cheese omelet. There is sobering news for egg lovers who have been happily gobbling up their favorite breakfast since the 2015-2020 Dietary Guidelines for Americans no longer limited how much dietary cholesterol or how many eggs they could eat. A large, new Northwestern Medicine study reports adults who ate more eggs and dietary cholesterol had a significantly higher risk of cardiovascular disease and death from any cause. "The take-home message is really about cholesterol, which happens to be high in eggs and specifically yolks," said co-corresponding study author Norrina Allen, associate professor of preventive medicine at Northwestern University Feinberg School of Medicine. "As part of a healthy diet, people need to consume lower amounts of 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 consumed foods. One large egg has 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 high cholesterol content, said lead author Wenze Zhong, a postdoctoral fellow in preventive medicine at Northwestern. The study will be published March 15 in JAMA. The great debate Whether eating dietary cholesterol or eggs is linked to cardiovascular disease and death has been debated for decades. Eating less than 300 milligrams of dietary cholesterol per day was the guideline recommendation before 2015. However, the most recent dietary guidelines omitted a daily limit for dietary cholesterol. The guidelines also include weekly egg consumption as part of a healthy diet. An adult in the U.S. gets an average of 300 milligrams per day of cholesterol and eats about three or four eggs per week. The study findings mean the current U.S. dietary guideline recommendations for dietary cholesterol and eggs may need to be re-evaluated, the authors said. The evidence for eggs has been mixed. Previous studies found eating eggs did not raise the risk of cardiovascular disease. But those studies generally had a less diverse sample, shorter follow-up time and limited ability to adjust for other parts of the diet, Allen said. "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. "We found cholesterol, regardless of the source, was associated with an increased risk of heart disease." Exercise, overall diet quality and the amount and type of fat in the diet didn't change the association between the dietary cholesterol and cardiovascular disease and death risk. The new study looked at pooled data on 29,615 U.S. racially and ethnically diverse adults from six prospective cohort studies for up to 31 years of follow up. It found: Eating 300 mg of dietary cholesterol per day was associated with 17 percent higher risk of incident cardiovascular disease and 18 percent higher risk of all-cause deaths. The cholesterol was the driving factor independent of saturated fat consumption and other dietary fat. Eating three to four eggs per week was associated with 6 percent higher risk of cardiovascular disease and 8 percent higher risk of any cause of death. Should I stop eating eggs? Based on the study, people should keep dietary cholesterol intake low by reducing cholesterol-rich foods such as eggs and red meat in their diet. But don't completely banish eggs and other cholesterol-rich foods from meals, Zhong said, because eggs and red meat are good sources of important nutrients such as essential amino acids, iron and choline. Instead, choose egg whites instead of whole eggs or eat whole eggs in moderation. "We want to remind people there is cholesterol in eggs, specifically yolks, and this has a harmful effect," said Allen, who cooked scrambled eggs for her children that morning. "Eat them in moderation." How the study was conducted Diet data were collected using food frequency questionnaires or by taking a diet history. Each participant was asked a long list of what they'd eaten for the previous year or month. The data were collected during a single visit. The study had up to 31 years of follow up (median: 17.5 years), during which 5,400 cardiovascular events and 6,132 all-cause deaths were diagnosed. A major limitation of the study is participants' long-term eating patterns weren't assessed. "We have one snapshot of what their eating pattern looked like," Allen said.