The Great Egg Debate: Are Eggs Good or Bad for Health?
Eggs are one of my favorite foods in the world. I could have eggs for breakfast, lunch and dinner. Eggs Florentine is in my top 5 favorite meals. So when clients or friends tell me that their doctors have told them to reduce egg consumption to prevent high cholesterol, it makes me want to scream. So let’s settle the Great Egg Debate: are eggs good or bad for health?
Last month I had 3 clients ask me some version of :
- “Should I be eating eggs?”
- “Aren’t eggs going to increase my cholesterol?”
- “Should I just eat the eggs whites?”
When I asked friends and family what they want me to blog about the first suggestion came from my friend Joanna and she wanted to know, once and for all, if eggs were good or bad for us. So let’s dive in and look at how this egg controversy started, the truth about eggs and their effect on our body.
Warning: this post contains a high number of egg yolks (aka jokes).
How did this controversy start?
For decades the American Medical Association (AMA) has provided guidelines for upper the limits of nutrient intake such as cholesterol. Their daily recommended limit is 300 mg. One large egg contains 168-210 mg of cholesterol (most of it in the yolk). So eat two eggs and you’ve blown your daily limit. This has caused years of backlash against the poor old yolk. Doctors advise against eating more than 2-3 eggs a week, and recommend total avoidance for those with heart disease, high cholesterol and diabetes.
I’m here to tell you that most of the fear around eggs is totally eggs-agerated. It’s based on an oversimplification of what cholesterol is and how it works in our body. In order to understand if eggs are good for us, we must first understand what’s in them.
So let’s get crackin’! (See what I did there? tee hee)
What is cholesterol? And what in the world is HDL and LDL?
Eggs are a good source of something called HDL cholesterol. Cholesterol is a lipid, which is a water-insoluble fat. Since it cannot dissolve in water, it needs to attach to a protein (forming a lipoprotein) to travel through the body. HDL (high-density lipoprotein) cholesterol is the “good” cholesterol (and I remember that with an easy mnemonic; H = Happy). LDL (low-density lipoprotein) cholesterol is the “bad” cholesterol ( L = Lousy).
Stay with me now! The protein in HDL coats the lipid (fat) molecules all the way around. Think of it as a sexy Ferrari. It’s smooth and aerodynamic. It zips through the blood stream without stopping, delivering the cholesterol directly to the liver.
The LDL molecules have more cholesterol and less protein. So these are more like a 1985 Chevy Cavalier. The ride is not very smooth, and these little buggers run into our arterial walls, leaving bits all over the place (which is the start of arterial plaque). HDL molecules can pick up the LDL’s and give them a ride to the liver. However, if we have more of the crazy LDL’s around than the responsible HDL’s, then the ratio gets out of whack. This is why we need more HDL cholesterol in our blood than LDL.
Now here’s the shocker…
Your body produces ~75% of the cholesterol it needs!
That’s right folks. Our liver and small intestine actually produce. Your body produces both LDL and HDL cholesterol and it tweaks the production on how much cholesterol you are getting from your diet.
Now you might be saying, “I thought cholesterol is bad for you. Why is my body producing something that’s doing it harm?”.
Your body needs cholesterol!
That gorgeous bod of yours needs cholesterol for:
- Making hormones! Estrogen, testosterone etc. are all cholesterol-based hormones. If you don’t have enough cholesterol in your body, that can eventually lead to hormonal imbalance. Yikes!
- Naturally producing vitamin D in the body (which in turn gets used for strong bones and teeth)
- Forming protective cell membranes (talk about a building block)
- Making bile to digest fat. Bile is also needed to absorb vitamins A, D, E and K
Reset your Eggs-pectations
Let’s review 3 key facts:
- Your body actually needs cholesterol
- Not all cholesterol is created equal (I’m lookin’ at you LDL!)
- Eggs contain the “happy” cholesterol, HDL
You might be saying to yourself, “Kimi, then what are all these studies I keep hearing about eggs being bad for you?”. I’m here to tell you that you can pick any side of an argument and find 10 studies to support that side. However, being an engineer and having taught nutritional research for years at the Canadian School of Natural Nutrition, I appreciate advice backed by science. So let’s not egg-nore the evidence.
- No connection found between egg consumption and and increase of LDL cholesterol and heart disease (http://www.ncbi.nlm.nih.gov/pubmed/16340654)
- A controlled trial showed folks with metabolic syndrome (insulin resistance, pre-diabetic) that were instructed to eat whole 2-3 eggs/day actually lost weight and maintained or improved their blood cholesterol levels (http://www.ncbi.nlm.nih.gov/pubmed/23021013)
- Eggs increased levels of HDL cholesterol in a weight-loss diet focused on adult men (http://www.ncbi.nlm.nih.gov/pubmed/19369056)
- A meta-analysis (a summary of several studies) based on 8 articles and 17 studies found no connection between consuming one egg a day and an increased risk in coronary heart disease or stroke. In fact, increased egg consumption reduced risk of stroke (http://www.bmj.com/content/346/bmj.e8539)
- A large study of risk of cardiovascular disease in men and women found no correlation between consumption of eggs and heart disease (http://jama.jamanetwork.com/article.aspx?articleid=189529)
Egg-cellent for Health
Eggs are one of the most nutritious and delicious sources of protein out there. One large egg contains:
- Only 77 calories
- 6 grams of protein. The amino acid profile of eggs is absolutely fab!
- Choline: 35% of daily intake (an important nutrient for the brain)
- Selenium: 28% (lowers risk of cancer)
- Biotin: 27%
- Vitamin B12: 23%
- Vitamin B2: 20%
- Loaded with Lutein and Zeaxanthin: antioxidants that significantly reduce the risk of macular degeneration and cataracts
It’s important to note that most of these nutrients are found in the yolk. So when you make an omelette with egg whites, you are missing out on a ton of vitamins and minerals. The white part primarily contains protein.
Egg-ceptions to the Rule. When to Skip the Yolk?
- Folks with a family history of hypercholesterolemia
- Those with Type 2 Diabetes. The research in this area is contradictory. Some studies show an increased risk of heart disease related to egg consumption. Some show the opposite. To error on the side of caution, I would recommend limit your consumption of egg yolks if you have Type 2 Diabetes
- Athletes trying to trim down should remove the yolk and still get the protein
The Bottom Line
Eggs don’t increase blood cholesterol levels, increase your risk of heart disease or clog your arteries. In fact, a diet high in saturated fats (animal protein like bacon, deep fried foods), refined carbohydrates (white bread, pizzas, pasta, white rice) and sugar (cookies, pastries) put you at a much higher risk of getting heart disease and a bunch of other lifestyle related diseases such as diabetes, cancer and Alzheimer’s.
So go ahead and enjoy your eggs. My brain is scrambled. I’m egg-hausted from telling egg yolks.