Eggs have long gotten a bad rap as a cholesterol-raising, artery-clogging food that offer little beneficial nutrition.
But they’ve also been praised as one of the most nutrient-dense foods on the planet.
So, which is it? Are eggs really all that bad for your health?
Digging into even the most recent studies, it seems this long-held controversy continues.
Here, we’ll discuss the nutritional value of eggs and their potential benefits, as well as dissect the conflicting evidence on eggs to determine whether or not they belong in a healthy, well-balanced diet.
Nutritional Value of Eggs
Since eggs hold the macro and micronutrients required to produce a baby chick, they’re loaded with vitamins, minerals, protein, and even some healthy fats.
The majority of eggs consumed come from chickens, so we’ll focus on the nutrition content of a single chicken egg.
One large hard-boiled egg (50 g) contains roughly (1):
- Calories: 77.5
- Protein: 6.3 grams
- Fat: 5.3 grams (saturated fat: 1.6 grams)
- Omega-3 fatty acids: 39 mg
- Vitamin A: 293 IU, 6% of the RDA
- Vitamin B2 (Riboflavin): 0.3 mg, 15% of the RDA
- Vitamin B5 (Pantothenic Acid): 0.7 mg, 7% of the RDA
- Vitamin B9 (Folate): 22 mcg, 5% of the RDA
- Vitamin B12: 0.6 mcg, 9% of the RDA
- Vitamin D: 17 UI, 4% of the RDA
- Choline: 113 mg
- Iron: 0.6 mg, 3% of the RDA
- Phosphorus: 86 mg, 9% of the RDA
- Selenium: 15.4 mcg, 22% of the RDA
- Zinc: 0.5 mg, 4% of the RDA
- Cholesterol: 212 mg, 71% of the RDA</>
As you can see, eggs are rich in vitamins—in fact, they contain every one except vitamin C. They’re also excellent sources of choline and minerals like phosphorus, iron, selenium and zinc.
Eggs are a versatile food and can be hard-boiled, soft-boiled, poached, scrambled, fried, or baked. The nutritional value remains similar no matter the cooking method.
The egg white holds almost 88% water and about 10% protein, while the egg yolk carries much of the other nutrients, including fats, vitamins and minerals (2).
This means if you want to get the most nutritional benefit from an egg, you’ll want to eat the whole thing.
Also, the color of the egg shells (typically white or brown) has no difference on the nutrition inside. The color just depends on the breed of the chicken.
Conventional vs. Organic vs. Free Range vs. Pasture Eggs
There are many different nutrition labels on eggs, and it can be hard to decipher which is the best option.
Here’s a quick guide to what these labels mean:
- Conventional Eggs: While the carton will certainly not advertise “conventional,” these types of eggs often come from hens that are likely living in cages or especially tight quarters, who are fed grains (and sometimes animal byproducts) and may be treated with antibiotics or hormones.
- Organic Eggs: Organic means the hens were fed organic feed (non-GMO grains) and not treated with antibiotics or hormones. They don’t live in cages and must have access to outdoor areas.
- Free-Range or Cage-Free Eggs: The definitions of these terms are often stretched. Cage-free means the hens are not raised in a cage, but they could still be living in crowded conditions. Meanwhile, free-range chickens have the option to roam outdoors.
- Omega-3 Enriched Eggs: These come from hens (often conventionally raised) that are fed on a diet that is supplemented with omega-3 fat sources like flaxseed or algae.
- Vitamin D Enriched Eggs: Similar to omega-3, these come from hens that are fed on a diet that is supplemented with vitamin D. One study found that a vitamin D-enriched egg can provide up to 500 IU vitamin D, which already offers the minimum amount recommended (3).
- Pastured Eggs: These eggs come from chickens who spend their time roaming outside, mostly feeding on the pasture (including insects) and some commercial grain-based feed.
According to various studies, hens that have access to the outdoors, especially those that are pasture-raised, are your best option, nutrition-wise.
For example, hens that have the ability to roam outside can produce eggs that contain some 3-4 times the amount of vitamin D in their yolks versus their conventional counterparts (4).
Another study found that eggs from pastured hens contained twice as much vitamin E and 2.5 times the omega-3 fats of caged hens (5).
Also, don’t fall for eggs that are simply touted as “vegetarian.” This simply means the chickens have only been fed grains. Pastured eggs are not vegetarian. Beware that this label offers no description of the conditions the hens are living in or the quality of the feed.
Summary: Eggs are rich in protein, healthy fats, and several vitamins and minerals including vitamin A, vitamin B12, selenium and zinc. Most of these nutrients are found in the yolk. There are nutritional differences in eggs depending on the feed and conditions of the hens. Pastured eggs tend to offer more nutrition than their conventional counterparts.
Health Benefits of Nutrition in Eggs
As seen above, eggs are rich sources of protein and essential vitamins, minerals and omega-3 fatty acids.
These nutrients offer many excellent health benefits.
1. Rich in Choline
Choline is essential for brain development, cellular growth and maintenance, bone integrity, nerve function and other critical processes.
One large egg contains about 113 mg of choline. The Adequate Intake (AI) for choline is 550 mg/day for men and 425 mg/day for women. Along with liver, eggs are one of the richest sources of this vitamin B-like nutrient.
Choline aids in the synthesis of acetylcholine, a neurotransmitter involved in functions like memory storage and muscle control. It also helps lower the amount of amino acid homocysteine in the blood, which has been linked to heart disease (6).
2. Good Source of Vitamin D
Vitamin D is the most common deficiency in the Western world.
It’s especially important for bone strength, the immune system and mental health.
The recommended daily intake is 400-800 IU (10-20 micrograms). However, you should be consuming more if you’re getting limited sun exposure. Several scientists also believe that an intake of over 1,000 IU (with a safe upper limit of 4,000 IU) is optimal for most people (7, 8).
To get the most vitamin D, choose pastured, free-range, or vitamin D-enriched eggs. As mentioned above, a vitamin D-enriched egg could contain upwards of 500 IU.
3. High-Protein, Low-Calorie Food
As a high-protein and low-calorie food, eating eggs regularly can support weight loss.
One whole egg contains roughly 77 calories and 6.3 grams of protein. This means they are low-calorie but filling and satiating. High-protein foods like eggs have been shown to increase fullness and reduce food intake, and boost metabolism by up to 100 calories per day (9).
If you choose eggs over a bagel for breakfast, you could even see up to 65% greater weight loss in just 8 weeks (10).
4. Supports the Immune System
Selenium and vitamins A and B12 are especially important for a strong immune system, and eggs are rich in all three.
5. Protects the Eyes
Eggs also contain high levels of lutein and zeaxanthin, two major carotenoids that work as antioxidants in the eye and throughout the body.
Consumption of one egg per day can increase the concentration of both lutein and zeaxanthin in the blood (14).
Along with keeping the eyes healthy, lutein has also been associated with improved cognitive performance (17).
6. High in Omega-3s
Most people also don’t get enough omega-3 fatty acids in their diets.
This specific type of fat is a powerful anti-inflammatory that offers a wide range of benefits, including reduced risk of cancer, Alzheimer’s disease, depression and other conditions (18).
Pastured eggs are your best bet, as they can offer more than double the total omega-3s compared to those from caged hens. Omega-3-enriched will also help boost your intake (5).
7. May Reduce the Risk of Cardiovascular Disease
Thanks to several of the nutrients mentioned above, eggs have the potential to protect the cardiovascular system, too.
Even though eggs are often looped in with meats and saturated fats as some of the biggest culprits in cardiovascular disease (CVD), the evidence doesn’t always back that up.
In one study on nearly half a million adults in China, daily egg consumption (about 1 per day) was associated with a lower risk of CVD and a 26% reduced risk of haemorrhagic stroke (19).
Another one found that participants with pre-diabetes or type 2 diabetes that were put on a high-egg diet (at least 12 eggs per week) saw no significant difference in CVD risk factors after 6 months (20).
Still, other studies have found eggs to be a risk. A recent one looked at data collected between 1985 and 2016 from nearly 30,000 participants and concluded that “high consumption of dietary cholesterol or eggs was significantly associated with higher risk of incident cardiovascular disease and all-cause mortality.”
However, after adjusting for total cholesterol consumption, they found that this association was no longer significant when it came to eating eggs, so it’s not clear whether the eggs are really the bad guys (21).
Summary: Eggs are rich in choline, which helps with brain development and the nervous system, and vitamin D, an essential nutrient for bone strength and mental health, among other functions. Consuming eggs can also support weight loss, the immune system, and eye health, and may reduce the risk of cardiovascular disease.
Do Eggs Affect Your Cholesterol?
At roughly 212 mg each, egg yolks are indeed high in cholesterol.
This amounts to over 70% of the daily recommended amount of cholesterol (300 mg)—or at least the previous recommendation. Current nutrition guidelines dropped this limit, given newer evidence that the cholesterol you eat, including from eggs, doesn’t raise total cholesterol levels in the blood.
Instead, the majority of cholesterol in the body is produced by the liver, and your liver will adjust the amount it makes by what you eat. The more cholesterol you consume, the less your liver will produce (22).
On top of that, not all cholesterol is bad. It’s essential for building cells and producing hormones. And what eggs do is actually raise HDL (the “good”) cholesterol.
As HDL goes up, total and LDL (the “bad”) cholesterol levels usually aren’t affected (25).
That said, excessive cholesterol intake may cause moderate increases in blood cholesterol levels (both HDL and LDL), but only when you count in numerous other factors like total caloric intake and amount of fats and fiber in the diet (26).
While the evidence is still fuzzy, it seems that consuming eggs will have no negative effect on the cholesterol levels of healthy individuals.
Summary: Egg yolks are high in cholesterol, but eating them won’t necessarily affect your total blood cholesterol levels. If anything, they can raise HDL (the “good”) cholesterol.
How Many Eggs is Healthy to Eat?
The number of eggs that are healthy to eat is still up for debate, and the science is often conflicting.
For one, it’s hard to find a study where participants eat more than three whole eggs per day.
Results will also differ according to the type of eggs consumed (e.g. conventional vs. pastured), how the eggs are cooked (e.g. poached vs. fried) and several other dietary factors.
The American Heart Association (AHA) says one egg a day is a good part of a healthy diet, but you’re likely safe eating a few more.
Summary: There’s no set recommendation for a safe number of eggs to eat daily. As of now, it seems that at least one a day is a good addition to a healthy diet.
Are Eggs Good or Bad for You?
Even though eggs are still blamed for causing high cholesterol and cardiovascular disease, the evidence is mostly lacking.
In fact, eggs pack a major nutritional punch in a filling high-protein, low-calorie package.
Eggs are provide some great nutrition, including choline, vitamins A, D, and B12, selenium, zinc, phosphorus, and omega-3 fatty acids.
All of these are found in the yolks.
So, if you want to get the most out of an egg, eat the whole thing.
Also, opt for pastured eggs whenever possible to get the most nutritional benefit.
Eating eggs can support weight loss, brain health, eye health, mental health, the immune system, and even protect against cardiovascular disease.
Yes, eggs may be beneficial for the heart, too, even though they contain a high amount of cholesterol.
That’s because the cholesterol you eat doesn’t necessarily affect the total cholesterol in your blood.
If anything, consuming eggs will simply raise HDL (the “good”) cholesterol.
This means an egg a day (or more!) can be an eggcellent part of a healthy, well-balanced diet.