Trying to maintain a healthy diet according to the latest evidence can be an incredibly stressful process for any would-be-dieter. Depending on who you ask, you can find yourself getting entirely contradictory advice on what to eat, what to avoid and generally how to design a healthy diet. And it’s no wonder that the information we receive is so conflicted either: every few years it seems that a new study comes along and contradicts everything we thought we knew about which foods are healthy or unhealthy.
Eggs in general and yolks in particular are an especially good example of this. First, we were told that eggs were a great source of protein for athletes and were shown films where characters downed them raw. Raw eggs were a favorite of old-time strongmen too. Then we were told not to eat raw eggs anymore because they could contain salmonella. Then that was largely dealt with, but we were warned against possible biotin deficiency as caused by raw eggs. Opinion on whether to cook eggs or not was split.
Next, it transpired that egg yolks were high in cholesterol. As it was thought at the time that dietary cholesterol was one of the main contributors to increased heart disease risk, we were advised to eat just the whites.
Then we learned that dietary cholesterol from saturated fats actually didn’t increase heart disease risk (1, 2) and egg yolks were fine again. But then recently in 2012, a study published in Atherosclerosis and picked up by the Daily Male, claimed that eating egg yolks actually would be a risk factor in coronary heart disease and was even ‘as bad as smoking’ (3).
Dear oh dear, what are we to believe?
The Truth About Egg Yolks
What’s important to recognize here, is that this latest 2012 study is only one study that stands in the face of mounting evidence that saturated fats and dietary cholesterol don’t lead to heart disease. The NHS analyzed the study (4) and concluded that it was not tightly controlled enough to draw and major conclusions. Average egg yolk consumption was evaluated through questionnaires and may not have been accurate, the study did not account for confounding variables (those who ate more egg yolks likely also ate other unhealthy foods) and the heart arteries were not even examined. In short, the headline that ‘egg yolks are as bad as smoking’ is a very reactionary and inaccurate headline.
Conversely, egg yolks are actually a great source of amino acids and together with egg whites provide a complete source of essential amino acids (they are also one of the few sources that do). Egg yolk aids the absorption of protein from the egg whites and also provides much of the flavor, which are two more compelling reasons to leave it in. In fact, in some studies (‘Eat Eggs and Cut Your Cholesterol Too’, Ezzell, C. 1992), it has been found that yolk and other fats can actually cut your cholesterol.
With all this in mind, how do you proceed?
At the moment, it seems opinion is swaying in the direction of ‘eggs are healthy’ again. As a great source of amino acids and a very tasty and versatile ingredient, this will be good news to many people. There’s no need to cut scrambled egg out of your morning routine just yet!
On the other hand though, all this swaying back and forth should demonstrate to you just how uncertain and tenuous any health advice is and there are still those that suggest eggs could pose a risk (5). The secret really, is to adhere to the old adage of: ‘everything in moderation’. Eggs are very good for you, but they may have negative impacts if you eat gross quantities. Be sensible, listen to your body and don’t get too carried away with any new study or piece of advice that you stumble upon.