For years, people who enjoy a daily egg have been warned they might be raising their cholesterol levels. However, a significant new study published in 2025 turns this long-held belief on its head, suggesting that eggs could be far better for your heart than previously thought.
The Study That Cracked the Cholesterol Myth
Research from Harvard Health, published in the July 2025 issue of The American Journal of Clinical Nutrition, indicates that dietary cholesterol from eggs might not be the primary driver of high LDL ("bad") cholesterol. Instead, the study points the finger squarely at saturated fat intake as the greater health concern.
The investigation involved 48 adults with elevated LDL levels who followed three different five-week diets in rotation. The diets were designed to isolate the effects of cholesterol and saturated fat: a high-cholesterol, low-saturated fat diet including two eggs daily; a low-cholesterol, high-saturated fat diet with no eggs; and a high-cholesterol, high-saturated fat diet containing one egg daily.
Saturated Fat, Not Eggs, is the Key Driver
The results were revealing. Across all participant groups, increases in harmful LDL cholesterol were strongly linked to the amount of saturated fat consumed, not the dietary cholesterol from eggs. In fact, participants who ate two eggs every day actually saw their LDL levels decrease, provided their overall diet remained low in saturated fat.
The study identified the main sources of these LDL-raising fats as foods like beef, lamb, pork, processed meats, butter, cheese, ice cream, and palm oil. It concluded that while cardiovascular disease remains a leading cause of death, and dietary cholesterol has historically been a focus of guidelines, saturated fat has a more substantial impact on blood cholesterol levels.
The Nutritional Powerhouse in Your Kitchen
Far from being a villain, the study highlights eggs as a unique food source—rich in dietary cholesterol but low in saturated fat. Contrary to traditional views, the research notes that egg consumption does not adversely affect blood lipids or increase cardiovascular disease risk. Some evidence even suggests potential cardioprotective effects, possibly due to eggs improving HDL ("good") cholesterol or their high choline content, which benefits lipid metabolism.
Eggs are also packed with vital nutrients. On average, a single egg contains 75 calories, 5 grams of fat, 6 grams of protein, and essential vitamins including A, D, and B12. They are a key source of the nutrient choline. Furthermore, egg yolks contain the antioxidants lutein and zeaxanthin, which are highly bioavailable and crucial for eye health, protecting tissues from sunlight damage and improving vision.
This pivotal research encourages a shift in perspective, suggesting that for most people, enjoying eggs as part of a balanced diet low in saturated fats is not a health risk but could be a beneficial choice.
