Eggs: The Ultimate Guide
Eggs are one of those foods that the media have named angel, then devil and then angel again. What should we believe? Are they healthy or not? Spoiler alert! Deviled eggs aren’t the devil anymore. This is a fairly comprehensive article, so if you have specific questions, scroll down to find your particular answers.
The Easter holidays this year got me to thinking about eggs as a healthy food because, well, it’s Easter, but also because I took care of my friend’s chickens over the holiday and was getting a bundle of fresh, pastured eggs every day. It seemed to me that recently, the health news on eggs had been changing, and I wanted to get to the bottom of it.
Here’s the good news: unlike butter, eggs’ recent angelic status comes from new, quality research, rather than a flawed study or two (see Better Butter for more about butter’s very different odyssey in the media). It’s a great time to rehash what we do and don’t know about eggs.
Cholesterol: another 80’s era dietary villain
If you read my story about butter, you’ll remember I talked a lot about a fatty acid villain: saturated fat. Eggs contain a very high amount of another dietary villain of my childhood: cholesterol. Though dietary saturated fat is still a bad guy, dietary cholesterol went in front of the parole review board in recent years and actually got a commutation of its sentence.
Before we dive in here, we need to get some things straight. There are three types of cholesterol that are relevant when we think about fat and health. First, there is dietary cholesterol, which is the cholesterol that is in foods we eat. The next two are blood cholesterols, which are cholesterols in our…blood. Though all are chemically similar, how they interact with our bodies is entirely different.
When you go to the doctor to get your cholesterol checked, it’s your blood cholesterol she’s concerned about. Blood cholesterol comes in two types. One is good (the type known as high density lipoprotein or HDL), the other is bad (low density lipoprotein or LDL). People with high HDL also in general have lower incidence of heart disease, while people with high LDL are very likely to have or get heart disease1. For LDL, researchers also have a good evidence for why it’s associated with heart disease: it is strongly involved in the process that builds up plaques in our arteries, which can lead to blockage. So it’s a good thing your doctor checks blood cholesterol.
But what about dietary cholesterol? Reasonable beings might assume that eating foods with a lot of dietary cholesterol would lead to high blood cholesterol—and this, indeed, is what scientists thought for several decades. After all, we are what we eat, right? But now there are strong experimental results that show high dietary cholesterol and high blood cholesterol are only very weakly related.2 These studies show that doubling the amount of dietary cholesterol raises blood cholesterol by only about 10%.1 It can also raise both good (HDL) and bad (LDL) cholesterol.3
That means, especially for some foods, beneficial nutrients may counteract the minor detriment of raising LDL a small percent. A good example is fish. Fish has a moderate amount of cholesterol, but also has a lot of omega-3 fatty acids3 (more about those below), a type of unsaturated fat which is very good for us. So the strong good more than counteracts the minor bad.
In terms of blood cholesterol, the real villain is…you knew it…saturated fat, which is high in dairy products (especially cheese and butter), many fried foods, and fatty cuts of meat. Saturated fat (and trans fat) is way, way more effective at raising blood cholesterol than dietary cholesterol 2 . The Joker of fats is at it again…
So, is dietary cholesterol an angel? Not exactly. Devil? Nah. Dietary cholesterol is less like a axe murderer and more like the vandal who breaks into your unlocked car at night and steals your scratched, only slightly serviceable 90’s vintage Nirvana and Lemon Heads CD’s from under the detritus in the foot well of the back seat. It may not be doing good, but you’re not exactly sad about it. This new story about cholesterol is probably why there is no good evidence connecting high egg consumption to high incidence of heart disease 2 .
(If you want to know more about cholesterol, check out this great interview with Dr. Walter Willett of Harvard University. The interview includes the effect of other foods on blood cholesterol, like refined grains and fiber.)
Why did the science on eggs change?
In order for the scientific community to understand the error in their assumptions, they needed big, long-term studies. Big, because that allows us to compute reliable statistics, and long because we are a long-lived species. How can we know that a person consuming 2 eggs per day as part of a healthy diet will not get heart disease by the time they are 55? We would need to track that person for many, many years.
Detailed analysis for cholesterol and other fatty acids only started in the 50’s4. If you think about it, we’ve hardly gone through one human life-span since such study started. In the 80’s, scientists only had hypotheses (guesses really) and results from very short-term studies to rely on. Now, we have several long-term studies to give us confidence. With this perspective on scientific history, it’s no longer surprising to me that just 3 years ago, in 2015, the government removed the limit on dietary cholesterol from their guidelines.
So the dietary cholesterol doesn’t make eggs bad for us. Are they good for us?
My sources say yes. They are a protein source that is quite low in saturated fat compared to other sources2, and we really want to eat less saturated fat. The fat in an egg is mostly mono- and polyunsaturated fat.
Eggs are also a good source of some micronutrients. These are nutrients in foods in small amounts, but that are critical for the proper functioning of our bodies. In particular, eggs have good amounts of vitamin B complex; vitamins D, E and K; and some antioxidants. They are also particularly high in selenium which helps our metabolism, digestion, thyroid function and protects against arthritis.5
Some scientists hypothesize that these nutrients (both the unsaturated fats and micronutrients) are what counteract any small rise in LDL that the dietary cholesterol creates.1
A couple of eggs fried in a highly unsaturated oil like avocado or canola? Sure thing!
So how many eggs are ok to eat?
Eggs still do have a lot of cholesterol, so we don’t want to go overboard. Two large studies show that one egg per day is not associated with increased risk of heart disease if you are otherwise healthy.2 However, one egg or more per day may be associated with some increase in the risk of diabetes.6 So less than one egg per day is probably best. But, between one and two eggs per day is not that risky. However, people with diabetes should consult their doctor, because studies show a higher consumption (>1 egg per day) increases the risk of heart disease and death from heart disease for such people.3,6
What’s more important is what eggs replace in our diet. We want to increase them in our diet in replacement of other foods with higher sugar, refined carbohydrates and/or bad fats. If they replace other protein sources that have more saturated fat, that’s great! But if they replace vegetables, fruits, whole grains, beans, or nuts, that’s not so great. For breakfast, use them to replace such foods as sweetened breakfast cereals, pancakes with syrup, muffins or bagels.2 For an appetizer, consider deviled eggs (see recipe below!) in replacement of foods like sausages or cheese.
What you eat with your eggs is also important. Having bacon with your eggs every morning will negate their benefit because of the saturated fat in the bacon. Smothering your omelet in cheese will do the same thing. However, chopping a boiled egg and adding it to your salad for a little protein is a good move.
Are omega-3 or pastured eggs worth the cost?
Trigger warning: crazy environmentalist here. Actually, I’m an “agrimentalist” because I believe that supporting small farmers, especially those that are good stewards of the environment (and most that I have met are). In this sense, it’s worth it to me to buy pastured eggs for the environmental and animal welfare benefits. This is because “pastured” means that the hens are allowed to wander grassy areas and eat greens and bugs in addition to their feed (for a comprehensive explanation of what egg carton labels mean, see the article “Eggs” from Harvard T.H. Chan School of Public Health—scroll down an open the link “Free-Range? Farm-Fresh? A look at egg carton labels”).
But what about for dietary health? Walk the egg aisle at your grocery store and you will see all sorts of health claims. The most prominent are claims about omega-3’s. What are omega-3’s and why should we care? I’ve spent hours on the internet trying to figure out why they are important and was baffled that I couldn’t find simple answers to the questions I had. Turns out, omega-3’s and their relationship to other fats and their function in the body is complex! I finally read a whole book on them4 and I feel I’m just starting to understand. Omega-3 fatty acids are a specific sub-type of polyunsaturated fatty acid, which is a specific sub-type of unsaturated fatty acid, which is a specific sub-type of fatty acid. My head spins just writing that sentence!
Let’s make it simple here and say two things. First, omega-3 fatty acids do many good things in your body. Examples are: damping inflammation, keeping tissues soft and resilient (especially important in places like the eyes and heart), inhibiting excessive blood clotting (which can trigger a heart attack or stroke), and actually reducing blood cholesterol.4 Second, what’s most important is that you consume less of something called omega-6 fatty acid in addition to consuming more omega-3. That’s because the ratio of these two fats in your total diet is what matters for health. Our typical western diet is high in omega-6 fatty acid, and that is a problem.
So let’s start with the bad news. The one quality study I found comparing pastured eggs to conventional eggs showed that there is little difference in omega-6 between them7. Shoot.
Nevertheless, pastured eggs have ~2.5x the omega-3’s as conventional eggs (~3.5% of total fatty acids as compared to 1.3%). This makes the ratio of omega-6 to omega-3 in the whole pastured egg (~5) less than half that of a conventional egg (~12)7, which is good. It is also true that so-called “omega-3” eggs have more omega-3 than conventional eggs. Hens that produce omega-3 eggs are fed flaxseed in their feed; flaxseed is very high in omega-3 fatty acids. But these hens may not be pastured.
But…unfortunately, the amount of omega-3 fatty acid in a pastured egg is not that much. About 0.08 g, which is pretty paltry compared to fish like salmon at 1.7 g or sardines at 1.2 g8.
Pastured eggs also have twice as much vitamin E than conventional eggs and 38% higher concentration of vitamin A7. You can tell when hens have been pastured because the egg yolk is a rich, dark yellow or orange. This is a general indication of higher micronutrient content, which may include some beneficial antioxidants or phytonutrients that science hasn’t confirmed yet.
So, will the nutritional differences between pastured and conventional eggs make a difference in your overall health? It’s unclear, but probably not on their own. But if you can afford them, they could be a good addition to an overall healthy diet. A pastured egg runs me $0.42-$0.50 whereas a conventional egg is much less at $0.07-$0.18. That’s a fair difference. Eggs are one of the things in my budget that I pay more for, because I am able to. I have those “agrimentalist” leanings, but I’m also allergic to fish, so getting more omega-3 in my diet from other sources is important for me. But if you really can’t afford them, don’t sweat it.
The least expensive pastured eggs I can buy in Colorado Springs are delivered to my house (sweeeet!) by Cluckin’ Chicken Ranch.
Are eggs a cost-effective way to get protein?
Here’s the great news about the egg redemption for budget-conscious healthy eaters. Eggs are a very cost-effective way to get protein. The following table compares pastured and conventional egg, beef and chicken prices:
Price per oz.
| Egg | Chicken Breast | Ground Beef | |
| Pastured | $0.21-0.25 | $0.32 | $0.22-$0.56 |
| Conventional | $0.04-0.09 | $0.16-0.21 |
$0.17-0.39
depending on % lean |
The ranges in the entries include different sources of the meat and eggs as well as the percent of fat in ground beef (lower percent fat is healthier, but also more expensive). Note the lowest price for grass-finished beef is from my local farmer’s market and is much less expensive than the lean conventional ground beef. In each case, the eggs are generally less expensive than the meat. In addition, the meat has more saturated fat than the eggs. Cross-comparison of pastured eggs to conventional chicken breast or ground beef shows a similar price range. So if you want the health benefits of the pastured eggs, use them to replace some of the chicken and beef in your diet, and you won’t need to spend more money.
Idea for replacing saturated-fat-heavy appetizers
What did I do with my cornucopia of pastured eggs over the Easter holiday? I turned those angels into devils. No, I didn’t inject saturated fats into the yolk…I made them into a delicious spin on that old classic, deviled eggs.
Jalapeno Deviled Eggs from Savor Paradise
Luckily, my cousin had just posted a new recipe to her food blog that I tried: Jalapeño Deviled Eggs. They are delicious! Because the other main ingredient in deviled eggs is mayonnaise, which is made of eggs yolks and oil, they are very low in saturated fat. Commercial mayonnaise producers use soybean oil, which is high in polyunsaturated fatty acids. If you decide to go for the bacon garnish, keep saturated fat low by using very small pieces (only one bacon slice divided between all the eggs). My health-conscious friend Elizabeth (of Sweet Elizabeth’s Gluten Free Bakery) suggested using a leaf of cilantro for garnish, if you want to avoid the bacon. I think I’ll try that next time!
If you want to increase the omega-3 fatty acids in your deviled eggs, make your own mayonnaise using pastured egg yolk and canola oil. But do be aware of the risk of eating raw egg yolks. If you feel comfortable doing it, make sure to thoroughly wash your eggs before you crack and separate them to avoid the possibility of salmonella poisoning.
Deviled eggs (or should we call them “angeled” eggs now?) are much healthier than many other protein-containing appetizers I can think of. Each deviled egg is ~1.5 oz. An equivalent amount of cheese and crackers, sausage and mustard, or sliders has comparable total fat to the egg, but the deviled eggs (even with the bacon) have ~37% less saturated fat and ~33% of the sodium in these other snacks. The eggs do have less protein than the other appetizers, but since Americans in general get plenty of protein, don’t worry about it. The deviled eggs also have little to no processed carbohydrates or sugar.
So should you eat those leftover Easter eggs? Absolutely! Their cholesterol won’t hurt you, their nutrients will probably help you, and they are a cost-effective way to eat protein.
Thanks to Susanna Maestas for the great egg inspiration and pictures of her chickens!
References
1 Powell, A., 2015, The entire egg, The Harvard Gazette, February 24.
2 The Nutrition Source, 2018, Eggs, T.H. Chan School of Public Health, accessed April 15.
3 The Nutrition Source, 2018, Ask the expert with Dr. Walter Willett: Cholesterol, T.H. Chan School of Public Health, accessed April 15.
4 Allport, S., 2006, The Queen of Fats: Why omega-3’s were removed from the western diet and what we can do to replace them, University of California Press, Berkeley, CA, 222 p.
5 Hyman, M., 2018, Food: What the heck should I eat?, Little, Brown & Co., New York, NY, 386 p.
6 Shin, J. Y, Xun, P., Nakamura, Y., and He, K., 2013, Egg consumption in relation to risk of cardiovascular disease and diabetes: a systematic review and meta-analysis, American Journal of Clinical Nutrition, v. 98, p. 146-159.
7 Karsten, H. D., Patterson, P. H., Stout, R. and Crews, G., 2010, Vitiamins A, E and fatty acid composition of the eggs of caged hens and pastured hens, Renewable Agriculture and Food Systems, v. 25, no. 1, p. 45-54.
8 National Institutes of Health, 2018, Omega-3 fatty acids, Fact Sheet for Health Professionals, accessed April 15.
