New Evidence on Eggs and Heart Health with Norrina Allen, PhD
Norrina Allen, associate professor of preventive medicine at Northwestern University Feinberg School of Medicine, shares the results of a large new Northwestern Medicine study that finds adults who ate more eggs and dietary cholesterol in general had a significantly higher risk of cardiovascular disease and death.
"We were particularly interested in eggs because it's one of the richest sources of cholesterol in the American diet, as well as processed meats and red meats. So, we examined all three of those dietary sources of cholesterol and what we found was that eggs were associated with increased heart disease."
— Norrina Allen, PhD
Associate Professor of Preventive Medicine in the Division of Epidemiology
The scientific community has sent us mixed messages about cholesterol consumption for decades. A new Northwestern Medicine study published in JAMA offers a new look at this issue and has found a good reason to limit how many eggs we eat. Norrina Allen, PhD, associate professor of preventive medicine at Northwestern, is the corresponding author of the new study. The study found that eating three to four whole eggs per week was associated with a 6 percent higher risk of cardiovascular disease and an 8 percent higher risk of any cause of death.
Norrina Allen: "One of the strengths of this study is that we had a really large sample. We collected information from individuals across the United States at different ages, across race, ethnicity. So we have a very diverse sample. And we followed them for a long time. We examined their diet, and then we followed them for over 30 years. And really determined what happened to them as they aged."
Allen's team was particularly interested in eggs because it's one of the richest sources of cholesterol in the American diet, along with processed meats and red meats. They examined all three of those dietary sources of cholesterol and found that eggs in particular were associated with increased heart disease.
Norrina Allen: "For every 300 milligrams of dietary cholesterol that you ate, you had a 17 percent higher risk of incident cardiovascular disease and an 18 percent higher risk of all cause death. And we found that if you took into account the cholesterol contained in eggs, that it was the cholesterol that was really explaining this relationship. And so that's really what's causing the heart disease and mortality we believe in this study."
Even in individuals who exercised and ate an otherwise healthy diet, the study found higher cholesterol consumption was associated with a greater risk of death from heart disease or other causes. This new finding is a good reason to take a closer look at the U.S. dietary guidelines, Allen says. The guidelines state that there's no appreciable relationship with cholesterol and your diet and your blood levels of cholesterol.
Norrina Allen: "We know that for some individuals that's true. The issue is that it's highly variable. There are some people who can eat a lot of cholesterol and their body metabolizes it quickly. For other people, that's not true. The more cholesterol that they eat, the more cholesterol that will be absorbed by their body. And there's very different patterns in the relationship between the cholesterol you eat and the cholesterol in your blood. So we believe that there is a stronger relationship between the food you eat and the cholesterol in your blood among individuals, for example, who are overweight. The liver just has enough fat in it that it can't absorb any more cholesterol from the diet and it gets put into the blood."
Allen says more work needs to be done to really understand what groups of individuals in the U.S. are susceptible to the harmful effects of high dietary cholesterol so that they can be flagged as high risk and interventions can be put in place to prevent them from developing heart disease.
Norrina Allen: "This is one large study. I think it's an important study that can be the basis of reevaluating those [U.S. dietary] guidelines, but we need additional studies to really support the public and making decisions about cholesterol foods, cholesterol containing foods, such as eggs and processed meats and red meat."
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Continuing Medical Education Credit
Physicians who listen to this podcast may claim continuing medical education credit after listening to an episode of this program.
Academic/Research, Multiple specialties
At the conclusion of this activity, participants will be able to:
- Identify the research interests and initiatives of Feinberg faculty.
- Discuss new updates in clinical and translational research.
The Northwestern University Feinberg School of Medicine is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to provide continuing medical education for physicians.
Credit Designation Statement
The Northwestern University Feinberg School of Medicine designates this Enduring Material for a maximum of 0.5 AMA PRA Category 1 Credit(s)™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.
Norrina Allen, PhD, has nothing to disclose. Course director, Robert Rosa, MD, has nothing to disclose. Planning committee member, Erin Spain, has nothing to disclose. Feinberg School of Medicine's CME Leadership and Staff have nothing to disclose: Clara J. Schroedl, MD, Medical Director of CME, Sheryl Corey, Manager of CME, Jennifer Banys, Senior Program Administrator, Allison McCollum, Senior Program Coordinator, and Rhea Alexis Banks, Administrative Assistant 2.