Saturated fat, not eggs, is the real driver of high LDL cholesterol. Find out what the experts think.
Decades of advice linking eggs with heart disease risk needs a rethink with researchers finding that eating two eggs a day as part of a low saturated fat diet can actually reduce LDL cholesterol.
The findings, published in the American Journal of Clinical Nutrition, add to growing evidence that saturated fat, and not dietary cholesterol from eggs, is the major dietary driver of elevated LDL cholesterol and cardiovascular risk.
In the randomised crossover trial, researchers from the University of South Australia compared three diets in 61 adults over separate five-week periods, including a high cholesterol, low saturated fat diet including two eggs a day; a low cholesterol, high saturated fat diet without eggs; and a control diet high in both saturated fat and cholesterol.
Participants consuming the high cholesterol, low saturated fat diet had significantly lower LDL cholesterol levels compared with the control diet, while the egg-free high saturated fat diet produced no significant improvement.
Across all diets, saturated fat intake was strongly associated with LDL cholesterol levels, while dietary cholesterol was not.
The authors concluded that “saturated fat, not dietary cholesterol, elevated LDL cholesterol” and that consuming two eggs daily within a low saturated fat diet “lowers LDL concentrations, which may reduce CVD risk”.
Australian nutrition experts and heart health advocates say the focus of cholesterol conversations should shift away from restricting eggs and toward reducing saturated fat intake and improving overall dietary patterns.
Accredited practising dietitian Sharon Natoli said the findings reinforced what nutrition researchers had increasingly understood over the past decade.
“It was such a strong message through the 70s and 80s,” she said.
“It takes a long time to change perceptions when a dietary message is very strong.”
Ms Natoli said many people still assumed foods high in cholesterol automatically increased blood cholesterol.
“There’s the simplistic thought that if eggs contain dietary cholesterol, that’s going to influence your blood cholesterol,” she said.
“But dietary cholesterol has a much weaker effect on blood cholesterol than saturated fat.”
She said earlier studies linking eggs with cardiovascular disease had often failed to account for the foods commonly eaten alongside them.
“A lot of that early research came out of the [United] States where the most common way to have your eggs is eggs and bacon or eggs and sausages,” Ms Natoli said.
“The statistical analysis didn’t account for the fact that eggs were often accompanied by high saturated fat foods.
“When you’re able to take out the effect of saturated fat, the link with dietary cholesterol becomes much weaker.”
Heart Support Australia CEO Dr Christian Verdicchio said the latest evidence should encourage clinicians to focus more closely on overall dietary patterns rather than eggs in isolation.
“We know from the study that eggs on their own are not the issue,” he said.
“If you have them with the hash brown or the bacon or the sausages, those foods which are rich in saturated fats, that is the contributing driver.
“And so if you’re having eggs with avocado or a salad or these types of whole foods, then in actual fact, it’s a good thing for you.”
Ms Natoli said this distinction between dietary cholesterol and saturated fat remained one of the most important messages for healthcare professionals to communicate to patients.
“It’s important to distinguish dietary cholesterol from saturated fat because they do have different effects,” she said.
“Saturated fat stimulates the liver to produce more cholesterol.”
She said patients generally found it easier to understand dietary advice framed around whole foods rather than nutrients.
“It’s much harder for people to understand nutrients than to just understand whole foods,” Ms Natoli said.
“Eggs are kind of unique. They contain dietary cholesterol, but they’re also a very nutrient-rich package.
“They’ve got every vitamin except vitamin C. They’ve got minerals, protein, antioxidants and omega-3s.”
The study authors also noted eggs contained highly bioavailable lutein and zeaxanthin, along with choline, which may have beneficial effects on lipid metabolism.
Ms Natoli said eggs remained particularly valuable for older Australians, pregnant women and people following vegetarian diets because of their nutrient density and affordability.
“Eggs are a major source of choline, an essential nutrient for cognitive function and it’s difficult to meet choline requirements without eating eggs,” she said.
“That’s really important in pregnancy for fetal brain and spinal cord development
She also pointed to evidence showing eggs could be safely included in diets for people with type 2 diabetes and elevated cholesterol when consumed within healthy dietary patterns.
“The Heart Foundation’s position statement says people with existing high LDL cholesterol and diabetes can have up to seven eggs a week,” Ms Natoli said.
“But there was also a University of Sydney study looking at 12 eggs a week in people with type 2 diabetes or at risk of diabetes as part of a healthy balanced diet, and there was no effect on measures of diabetes or heart risk .”
Current Heart Foundation guidance states there is no limit on egg intake for healthy individuals, while people with type 2 diabetes or high cholesterol can consume up to seven eggs weekly as part of a heart healthy diet low in saturated fat.
Dr Verdicchio said the challenge now was ensuring healthcare professionals had the time and confidence to explain the evolving evidence to patients.
He said trusted organisations and evidence-based resources would play an important role in correcting outdated beliefs that had persisted for decades.
“One bad study can fuel information for years,” he said.
“Food can be high in cholesterol, but that’s not what causes cholesterol uptake. It’s actually saturated fats which cause cholesterol to increase.”
Dr Verdicchio said the renewed focus on eggs also provided an opportunity for broader discussions about dietary quality and cardiovascular risk.
“Having that conversation around what you’re having with those eggs is fundamentally important,” he said. “It’s a really good opportunity to discuss what else is going on in the patient’s diet.”
American Journal of Clinical Nutrition, July 2025
In partnership with Australian Eggs.
