Maybe eggs aren't bad for heart health after all

When it comes to heart health, eggs have been viewed as a problem food for a while now. The reason for this being that eggs are high in cholesterol and high cholesterol is associated with heart disease. However, a recent study has sought to find if this negative association is correct.

Are eggs damaging to heart health?​

A prospective controlled trial presented at the American College of Cardiology’s Annual Scientific Session has looked at the effects of eating eggs on cholesterol levels and other key markers related to heart health.

The ‘Prosperity’ trial, which took place over a four-month period, analysed results from 140 individuals over 50 years of age, who were classified as having a high risk of developing cardiovascular disease. The study group ate 12 or more fortified eggs a week, while the control group less than two eggs a week. High-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol levels were measured, in addition to other key markers of cardiovascular health such as lipid, cardiometabolic, and inflammatory biomarkers.

Patients had in-person clinic visits at the start of the study and visits at one and four months to take vital signs and have bloodwork done. Phone check-ins occurred at two and three months and patients in the fortified egg group were asked about their weekly egg consumption. Those with low adherence were provided with additional education materials.

Dr Nouhravesh and her team decided to look at the implications of eggs on heart health as eggs are a good source of vitamins and minerals, including vitamin D, B2, B5, B12, selenium and omega-3 fatty acids, and are a relatively inexpensive source of protein.

“We know that cardiovascular disease is, to some extent, mediated through risk factors like high blood pressure, high cholesterol and increased BMI and diabetes,” explains Dr Nina Nouhravesh, a research fellow at the Duke Clinical Research Institute in Durham, North Carolina. “Dietary patterns and habits can have a notable influence on these and there’s been a lot of conflicting information about whether or not eggs are safe to eat, especially for people who have or are at risk for heart disease.”

Results showed a -0.64 mg/dL and a -3.14 mg/dL reduction in HDL-cholesterol ('good' cholesterol) and LDL cholesterol ('bad' cholesterol), respectively, in the fortified egg group. While these differences were not statistically significant, the researchers said that eating 12 fortified eggs each week had no adverse effect on blood cholesterol. Looking at the additional key markers of cardiovascular health, researchers observed a numerical reduction in the total cholesterol, LDL particle number, another lipid biomarker called apoB, high-sensitivity troponin (a marker of heart damage), and insulin resistance scores in the fortified egg group.

“While this is a neutral study, we did not observe adverse effects on biomarkers of cardiovascular health and there were signals of potential benefits of eating fortified eggs that warrant further investigation in larger studies as they are more hypothesis-generating here,” added Dr Nouhravesh.

It’s important to note that this was a small single-centre study, meaning that the results are limited. It is also reliant on patients’ self-reporting of their egg consumption and other dietary patterns, which could result in inaccuracies. Another important factor to acknowledge is that it was also an ‘unblinded’ study. This means that patients knew what study group they were in and that information could have influenced their health behaviours.

What are the health benefits of eating eggs?​

Eggs have been linked to a whole host of health benefits, from providing a source of low-calorie energy to supporting mental health. 

They’re naturally nutrient rich, with an average serving of two eggs containing 82% of your daily vitamin D requirements, 50% of your daily folate requirements, 25% of your daily riboflavin (Vitamin B2) requirements and 40% of your daily selenium requirements. They’re also packed with protein, with a single egg containing around 6.3 grams of protein. 

Source: Prospective Evaluation of Fortified Eggs Related to Improvement in the Biomarker Profile for Your Health: Primary Results from the PROSPERITY Trial
Published online: 6 April 2024
DOI: https://www.acc.org/
Authors: Nina Nouhravesh, MD, et al.