Are egg yolks unhealthy?

My staple breakfast meal at a diner consists of bacon, rye toast, home fries, and two poached eggs with runny yolks. It may sound insanely weird, but my favorite part of breakfast is the moment I dip my rye toast into my runny egg yolks. However, I’ve always heard rumors that egg yolks are actually extremely unhealthy. Although eggs are a great source of iron, vitamins, and nutrients, they contain a large amount of dietary cholesterol. Excessive amounts of cholesterol can negatively affect heart health (Heid). So my question is, are egg yolks actually THAT unhealthy for me?

In 2012, a Canadian study was conducted to research this question. This observational study implemented an ultrasound test to observe the buildup of fat in the arteries of 1,231 adults. Every participant in this study was a regular at a vascular prevention clinic due to pre-existing signs of heart disease. The alternative hypothesis tested was the effect that a large consumptions of egg yolks had on heart disease. Although this is an observational study, reverse causation can be ruled out due to time, since heart disease cannot be the cause of food consumption that already occurred. As always, chance is an option in this experiment, and many third variables could affect the correlation, such as junk food consumption, lack of exercise, and hereditary risk of heart disease.


diagram of carotid artery found here!

Besides observing each participant’s carotid arteries via ultrasound, the researchers also asked every person to do the following:

  • Explain his/her personal history of smoking
  • List how many egg yolks he/she consumes in a week
  • Recall how long he/she had been eating this weekly amount of egg yolks

With this data and information, researchers concluded that the more a person smoked and the more egg yolks a person ate both increased a person’s risk for heart disease. However, there are quite a few faulty limitations that hold this study back. For starters, this is a single, small study, and is extremely exclusive considering the participants are already at risk for heart disease, and are all Canadian. Second, just as our intuition is lousy, so is our memory. Many participants could simply be generalizing their egg yolk consumption and cigarette smoking throughout the years. This study definitely highlights a correlation between smoking, egg yolk consumption, and increased risk for heart disease. However, it is not large enough or conducted strongly enough to prove any causation. Personally, I think the only way to conclude a strong correlation would be to conduct a meta-analysis of similar studies.

On the other side of the spectrum, this U.S. News article by Toby Amidor argues in favor of egg yolks. An important point brought up in Amidor’s article is the fact that other foods in our daily diets, such as meats and dairy, contain just as much fat as the average egg yolk. So, if we are told to avoid egg yolks for this reason, then shouldn’t we be avoiding chicken, beef, pork, yogurt, cheese, and milk as well? At that point, we would all basically be vegans! Amidor’s article also highlights the American Heart Association’s approval of the entire egg, not just the whites, and according to Blue Cross Blue Shield of Mississippi, other breakfast foods that complement morning eggs are the actual sources of bad cholesterol.


image found here!

What I’ve taken away from my time researching egg yolks is that the unhealthiness of an egg yolk probably exists, but not enough to cut yolks out of my diet completely, especially if I’m not at risk for heart disease. In reality, if my morning eggs are the fattiest foods I consume during the day, am I really doing that much harm to myself? Surely, people who are pre-disposed for heart disease may want to watch excessive egg yolk consumption, but observing a healthy diet as a whole instead of cheating oneself out of one specific food is a more well-rounded way of eating, and a happier one too!

7 thoughts on “Are egg yolks unhealthy?

  1. Luyi Yao

    Pollock and Redifer also provide egg yolks in the morning diet, so I think although maybe, probably, perhaps there is a correlation between egg yolks and heart disease, it is too inefficient to make any impacts. As the post mentioned that “more egg yolks a person ate both increased a person’s risk for heart disease”. So the amount of egg yolks we eat is very important. I think people usually would not intake too many egg yolks. Thus even though egg yolks cause some problem, it is not a big case.

  2. Michael A Lupo

    I have always heard of the egg yolk being unhealthy for you. I figured this was why many restaurants and diners offer egg white substitutes for your favorite breakfasts. High cholesterol runs in my dad’s side of the family, so as I can remember, my mom has been taking the yolks out of my dad’s eggs whenever she is cooking them. I, however, do not enjoy egg white omelets. I prefer regular eggs with the yolk included. Although people in my family have a history of high cholesterol, mine maintains a healthy level which allows me to continue to enjoy the egg whites and the yolk. In the future, I wonder if there will be further developments which provide more concrete evidence about whether or not egg whites are entirely bad for you. I believe that anything in moderation is ok, and as long as you are not eating egg yolks three times a day, seven times a week, you will probably be ok. I find it funny that the one study mentioned claims that other breakfast compliments are the true source of bad cholesterol. In an article found can here , many different breakfast options are described and proven to help lower your cholesterol as well as maintain it. Practicing a healthy, balanced diet can be one of the key factors to living a healthy lifestyle while you enjoy some of the foods you love.

  3. Jackson Grey Hope

    As a breakfast fanatic, I can’t imagine my diet without eggs in the morning. However, my mother has always told me to stay away from the yolk of an egg. Although this part of the egg contains more fat, I need to eat the egg yolk because as you said, it’s the best part! On the other hand, when I make eggs I often try and mix in an egg white, which takes away the fat and adds protein. This alone can decrease the chance of heart problems. If you are the kind of person that likes sitting with your feet up and watching TV all day, that is when you should be worried about the yolk part, but if you work out and exercise on a regular basis, as you said in your post, you shouldn’t be worried. I like how you incorporated other factors in this post, such as the correlation between smoking and egg yolk consumption, and how this can affect your health. Here is an article that discusses why egg whites are better than egg yolk, even if you aren’t the kind of person that sits on your couch and plays video games all day. Next time you go to whip up some eggs, try mixing it an egg white! This article will give you the nutrition facts for each one. Let me know what you think!

  4. Victor William Gregory

    I found this interesting because there was once a time in my house where we only bought egg whites because my parents were convinced that eating egg yolks was bad for our heart health. Needless it say it didn’t last very long. Although I found that the study that you used to be factual and reliable, it didn’t necessarily cover all of its bases. Although they mentioned third variables involved, they never explicitly mentioned how, what, or why they could have an effect. When i researched this topic i found this article. The article discusses what effects eating egg has on your body. I think that this is an interesting topic and i’m glad someone wrote about it. I can’t wait to see if this develops further than it already has.

  5. Danielle Megan Sobel

    Hello Mary! This breakfast sounds a lot like my favorite Saturday morning treat too (minus the bacon). Although I am not too keen on the flavor of it, I have never thought abut the health consequences behind a runny yolk. My dad however loves the yolk of a sunny side up egg, and I notice that is HIS favorite part, so the health factors you brought up in this blog got a hold of my attention. I wanted to know how much cholesterol was in an egg yolk, so simply by googling it I received an interactive way to change the type of egg and quantity to display a cholesterol. By using this table and measurements given in it, I can help make sure my dad does not eat too many egg yolks, which would increase his cholesterol by a lot.

  6. Julia R Martini

    I love breakfast food as well! An egg white omelet with spinach and onions is my every week Sunday brunch order. I too was confused when I recently heard that eggs are not that healthy for people. When I googled this topic, the first link that came up was an article with the title, “Eggs are worse than Cigarettes?”.
    Obviously the experiment that was conducted had to have many flaws but it was an interesting article to read. It explains why people think that eggs are bad for the body and what makes eggs unhealthy. It isn’t so much the egg, it’s more of the added items that we put in our eggs that makes people think they are harmful.

  7. Abigail Roe

    Mary, great blog post! I never heard of egg yolks being harmful to our health. I like how you used a lot of our scientific terminology from class. You included more than one study, which enhanced the credibility of your blog post and showed two different views. I think that eating the egg yolk in a dippy egg is not extremely unhealthy. It is my favorite part to dip my toast in it too! However, it would all depend on the person that is eating the egg yolk. Are they at risk for heart disease? How frequently do they eat egg yolk? These are all confounding variables that must be evaluated. A question I had while reading was about the first study done. Did they measure smoking habit as a confounding variable to the study? When I think of eggs, I think of the most healthy part being the yolk. I know you showed in the one diagram, that the egg white is a source of protein. I decided to look more into the health benefits of eating egg whites and this is what I found.

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