The trouble with eggs

I’ve noticed a troubling trend as I examine the 5 day food journals that I ask all new clients to fill in before their first appointment with me. While many people have taken on board that meat and dairy products are foods they should be cutting down on for their health’s sake, these same people are often eating up to 2 eggs per day, because they’ve been persuaded that eggs are health-promoting.

Even the nutrition student who’s currently doing clinic observation with me was surprised to hear me advise a client with multiple risk factors for heart disease to dump his daily egg. Her lecturers are teaching that egg consumption doesn’t raise blood cholesterol levels and that eggs are perfectly safe for people with, or at risk of, heart disease.

Let’s unpack the confusion and misinformation about eggs, beginning with the cholesterol issue.

Eggs are the major dietary source of cholesterol for Australians, with a single egg yielding anywhere between 200 mg and 370 mg of cholesterol depending on its size. This means that just 1-2 eggs per day can take you well over the maximum recommended daily intake of cholesterol, which is 300 mg.

But the standard dogma that you’ll hear trotted out by the Dietitians Association of Australia, the Heart Foundation and the government is that egg consumption has only a minimal effect on blood cholesterol level, and eggs are perfectly safe for everyone to eat, including those with, or at risk of, heart disease. In fact, the Dietitians Association of Australia is so keen on eggs, they advise that

“everybody should include them in their healthy eating plan”.

Yet research clearly shows that:

What gives? Why is there such enthusiasm for eggs in the face of studies like these? To understand this, you need to grasp two things.

  1. In the publish-or-perish environment of academia, there is constant pressure to produce new studies. In my Honours degree, I was told not to cite research more than 7 years old as it is considered ‘out of date’. Yet there’s no valid reason to discount the results of carefully-performed studies just because they weren’t published within the previous decade, especially when there have been no developments in measurement techniques or other methodological issues that might cause the results to be questionable.
  2. Vested interests take advantage of the constant clamour for new studies by funding research that is conceived, designed, and if necessary manipulated, to present their product in a favourable light.

Here is a case in point:

Back in 1992, a meta-analysis (analysis of data combined from multiple studies) pointed out that

“modest amounts of dietary cholesterol added to a cholesterol-free diet would be expected to most efficiently elevate serum cholesterol … [however] changes in serum cholesterol would be expected to be minimal if cholesterol was added to a diet already rich in cholesterol. Thus, changes in serum cholesterol when baseline dietary cholesterol intakes were high would be difficult to detect given the wide range of individual responsiveness to dietary cholesterol.”

Interestingly, only 29% of the studies included in this straight-shooting meta-analysis were funded by industry, primarily the egg industry.

9 years on, in 2001, another meta-analysis was published which concluded that

“Dietary cholesterol raises the ratio of total to HDL cholesterol and, therefore, adversely affects the cholesterol profile. The advice to limit cholesterol intake by reducing consumption of eggs and other cholesterol-rich foods may therefore still be valid.”

This time, 41% of the studies included in the meta-analysis were industry-funded.

But fast forward 12 years and a 2013 meta-analysis let dietary cholesterol off the hook, dismissing its effect on serum cholesterol as “modest” and “limited to population subgroups”.

The most striking fact about this study is that 92% of the studies it included were funded by industries that produce products high in cholesterol. Why does this matter? Because industry-funded studies do exactly what the author of the 1992 meta-analysis explained would make it difficult to detect any effect of added dietary cholesterol on blood cholesterol levels – they add eggs to a diet that’s already high in cholesterol.

Here’s an interesting example. The National Health and Medical Research Council cited this study, Consumption of One Egg Per Day Increases Serum Lutein and Zeaxanthin Concentrations in Older Adults without Altering Serum Lipid and Lipoprotein Cholesterol Concentrations in support of its claim (in the evidence brief for the Australian Dietary Guidelines) that “There is recent evidence to suggest that consumption of eggs every day is not associated with increased risk of coronary heart disease”. (It’s noteworthy that this evidence brief only includes egg studies from after the turn of the 21st century, when the egg industry’s War on Cholesterol Truth got underway.)

Yet, when I delved into the data, I quickly discovered that the cholesterol intake of the control group, which was NOT given an egg per day during the study period, was 312 mg per day.


No wonder the researchers were able to ‘prove’ that adding 1 egg per day to the diet didn’t hike up blood cholesterol levels in this group; their cholesterol intake was already so high, that adding extra dietary cholesterol from eggs wouldn’t make much difference.

The argument that we don’t need to worry about eggs because they don’t raise cholesterol in people whose cholesterol level is already too high (between 5 and 5.2, in this particular study), is like saying that smoking isn’t harmful, because compared to a pack-a-day smoker, a person who smokes a pack-and-a-half doesn’t seem to have an increased risk of lung cancer. The proper way to determine whether smoking causes lung cancer, of course, is to compare the risks of a life-long non-smoker and that pack-a-day smoker.

Likewise, if eggs are added to the heart disease-promoting Standard Australian Diet (SAD), there probably won’t be a noticeable increase in the risk of heart disease. But if you add eggs to the diets of vegans or even lactovegetarians whose cholesterol intake is quite low, you’ll see dramatic differences in cholesterol level and heart disease risk, as I described above.

Remember what happened to those lactovegetarian students who had 1 extra-large egg added to their daily diet? They started out the experiment with a daily intake of just 97 mg of dietary cholesterol, and ended up with a whopping 418 mg per day from adding the egg, which elevated their blood level of LDL cholesterol by 12% in just 3 weeks.

It’s not just cholesterol level that’s impacted upon by eggs. Coronary artery calcium (CAC), which is measured using a CT scan, is a powerful predictor of the risk of coronary heart disease, even in young people with no obvious signs of disease. A Korean study of over 23 000 people with no history of heart disease or high cholesterol found that those who ate 7 or more eggs per week had an 80% higher risk of CAC than those who ate less than one egg per week.

The high content of lecithin (also known as phosphatidylcholine) in eggs – roughly 250 mg in a single egg yolk – is also a problem. Gut bacteria and liver metabolism transform phosphatidylcholine into trimethylamine oxide (TMAO), which promotes the growth of the atherosclerotic plaques that cause heart attacks, peripheral vascular disease, most strokes and many cases of dementia.

No wonder that a 2013 meta-analysis (which included studies going back to the 1990s) demonstrate a clear link between egg consumption and heart disease, especially in diabetics, that follows a dose-response pattern – that is, the more eggs people eat, the higher their risk of cardiovascular disease and type 2 diabetes.

When even the industry-friendly US Department of Agriculture won’t permit the American Egg Board to describe eggs as ‘nutritious’ because of their high content of cholesterol, total fat and saturated fat (60% of the kilojoules/calories in eggs are from fat, and 27% of that fat is artery-clogging saturated fat), I’m left wondering why there’s such enthusiasm for eggs amongst dietitians, doctors and government.

Maybe it has something to do with the fact that the Dietitians Association of Australia receives corporate sponsorship from the Egg Nutrition Council, a supposedly ‘independent’ front group established by the Australian Egg Corporation which is the major marketer of eggs in Australia.

The Egg Nutrition Council very helpfully provides ‘educational’ programs for doctors, too, to persuade them to spruik the benefits of eggs to their patients. And the CSIRO is apparently perfectly happy for its senior scientists to be members of this industry front group.


This viper’s nest of blatant conflicts of interest goes far to explain the sorry state of nutrition education in Australia, and the appalling, disease-promoting advice that’s dished out to the public by health professionals whom they presume they can trust to give unbiased advice.

One of my clients was even told by his haematologist that eggs are so nutritious, humans could practically live on them alone. Really? Humans, who have no capacity to make vitamin C (unlike practically every other animal on the planet) and a high requirement for fibre and carbohydrate, could thrive on a food that contains zero fibre, zero vitamin C and practically zero carbohydrate, not to mention exceedingly low levels of calcium, iron, magnesium and most antioxidants? Well, blow me down with a chicken feather.

The bottom line: There’s nothing health-promoting about eggs. And be careful where your nutrition information is coming from. The food industry’s pockets are deep and its influence is pervasive.

Would you like expert guidance in sorting through the maze of seemingly contradictory diet information to develop an eating plan that’s perfectly tailored to you? Become an EmpowerEd member today!

Leave your comments below:

Leave A Response

* Denotes Required Field