Health
New Study Clears Eggs, Highlights Hidden Danger
Health Points
- Latest research finds eating two eggs a day may actually improve cholesterol levels in healthy adults
- Saturated fat, not dietary cholesterol, is the main driver of high LDL cholesterol
- Eggs can be part of a heart-healthy diet for most people, but those with certain health conditions should be cautious
The humble egg has been at the center of dietary debates for decades. But fresh research is putting that controversy to rest, especially for adults interested in aging healthfully. According to a recent study published in The American Journal of Clinical Nutrition, eating two eggs a day actually led to better cholesterol numbers in healthy adults.
Rather than blaming eggs for spikes in cholesterol, the study’s findings point to a different culprit: saturated fat. “When it comes to a cooked breakfast, it’s not the eggs you need to worry about—it’s the extra serve of bacon or the side of sausage that’s more likely to impact your heart health,” said Jon Buckley, PhD, senior study author and executive dean of the University of South Australia Allied Health and Human Performance Academic Unit.
For years, scientists were uncertain about eggs’ precise effect on cholesterol, since a single large egg contains about 200 milligrams of dietary cholesterol. That’s roughly two-thirds of the previously recommended daily maximum. But eggs are naturally low in saturated fat—just 1.6 grams—which makes them stand out from other high-cholesterol foods.
Sean Heffron, MD, preventive cardiologist at NYU Langone Heart, explained, “For much of the past two decades, we’ve had a pretty strong feeling that it’s saturated fat, far more than cholesterol [that raises LDL levels].”
This new clinical study put those feelings to the test by switching 61 healthy adults through three different diets over several weeks: one high in cholesterol and saturated fat with minimal eggs, another high in cholesterol but low in saturated fat with two eggs daily, and one low in cholesterol but high in saturated fat and no eggs. At the end of the study, saturated fat—not dietary cholesterol—was the factor raising LDL (“bad”) cholesterol. In fact, those on the egg-heavy diet saw an average LDL drop of 5.7 mg/dL compared to the control diet, while the egg-free diet had no such effect.
Jon Buckley remarked, “We were a bit surprised that the effect was so clear-cut.” However, readers should note that the Egg Nutrition Center—a division of the American Egg Board—provided some funding for the study.
So what’s really causing fluctuations in cholesterol? While it may seem intuitive that eating more cholesterol would raise blood cholesterol, your body doesn’t work that way. Most of your cholesterol is made by the liver, not absorbed from food. Eating more saturated fat prompts the liver to ramp up cholesterol output and slow down LDL removal, leading to higher levels in your bloodstream.
“There is evidence that when you increase your dietary cholesterol intake, your own production of cholesterol reduces to compensate,” Buckley explained.
Melissa Mroz-Planells, DCN, RDN, commented, “Dietary cholesterol isn’t the villain it was once thought to be.”
For most adults, that means eggs can be enjoyed as part of a balanced and heart-friendly diet. “Research shows that eating about one egg per day is safe for your heart,” Mroz-Planells said. But if you have high cholesterol, it’s wise to be a bit more careful. Michael Miller, MD, a cardiologist, emphasized that the recent findings might not apply to individuals with high LDL cholesterol or other health issues affecting cholesterol regulation.
Conditions like familial hypercholesterolemia—a genetic disorder—or certain thyroid and kidney diseases can lead to higher cholesterol even with normal diets. If this sounds like you, or if you’re concerned, registered dietitian Sharon Palmer, RDN, recommends using just the egg whites and skipping the yolks, as that’s where most cholesterol and saturated fat are found.
Finally, experts advise keeping an eye on your saturated fat intake overall. For optimal heart health, the American Heart Association suggests limiting saturated fat to no more than 13 grams per day. Eggs, as it turns out, can have a place at your breakfast table—just be mindful of what you serve alongside them.