There are so many ways to enjoy the humble egg: scrambled, fried, hard boiled, poached. Americans eat a lot of eggs — about 95 million dozen eggs annually, or approximately 279 eggs per person per year.

Egg consumption is on the rise, partly because of eggs’ versatility and partly because of their many health benefits. Today, people see eggs as a sort of superfood — low in calories, high in nutrients — but that wasn’t always the case.

For many years, eggs (or, at least, egg yolks) got a bad rap because of their high cholesterol levels. Until the publication of the 2015–2020 Dietary Guidelines for Americans, the U.S. Department of Agriculture recommended adults consume no more than 300 milligrams of dietary cholesterol each day. Considering a single yolk contains anywhere from 215 to 275 milligrams, that doesn’t leave much room for eggs at the table. Since the release of newer guidelines, however, eggs have been enjoying a comeback. 

Eating eggs every day can have a lot of positive benefits for your health, but there are a few things you should watch out for — and it’s important to know that not all eggs are created equal.

The reason people shied away from eating whole eggs for so many years was the mistaken belief that dietary cholesterol had a significant impact on blood cholesterol levels. It is true that eggs are high in dietary cholesterol, as a study in The Canadian Journal of Cardiology revealed.

Ironically, government guidelines cautioned against consuming too much dietary cholesterol for years, even though scientific evidence was pretty clear on the matter.

Way back in 1965, a paper published in Metabolism concluded that “for the purpose of controlling the serum level, dietary cholesterol should not be completely ignored but attention to this factor alone accomplishes little.” The researchers found that reducing dietary cholesterol by 50 percent only dropped blood cholesterol levels by about 7 mg/dL.

Research published in Current Opinion in Clinical Nutrition & Metabolic Care in 2006 concluded that for about 70 percent of people, eating eggs and other sources of dietary cholesterol has little to no impact on blood cholesterol levels. For the other 30 percent (known as “hyperresponders”), LDL (“bad”) cholesterol may go up significantly, but so does HDL (“good”) cholesterol, which balances things out. 

Not only can you stop worrying that your morning omelet is going to lead to a heart attack, but one type of egg may even help lower your triglycerides, a type of fat circulating in your body that has strong links to heart disease and stroke risk. Omega-3 eggs come from chickens whose feed has been enriched with omega-3 supplements such as flaxseed or fish oil.

A 2007 study in Nutrition, Metabolism & Cardiovascular Diseases noted that when chickens ate a feed that contained supplemental tuna oil, their eggs contained nine times the amount of omega-3s as regular chicken eggs. In the experiment, participants who consumed enriched eggs experienced a 16 to 18 percent decrease in their triglyceride levels.

Omega-3 eggs are pricier, but if you’re trying to lower your triglyceride levels, the extra cost may be worth it. A regular egg contains only about 25 milligrams of docosahexaenoic acid (DHA), one of the three types of omega-3s. Health professionals recommend healthy individuals get a combined total of 250 to 500 mg of DHA and EPA, another type of omega-3, daily. So while one regular egg won’t do much for you, one omega-3-enriched egg packs a considerable punch 100 to 500 milligrams.

You’ll probably be able to skip your mid-morning snack if you include a few eggs with breakfast. That’s because eggs are high in protein, containing 6 to 8 grams per egg. Compared to its macronutrient cousins carbs and fats, protein is the most filling macronutrient, as a 2008 study in The American Journal of Clinical Nutrition highlighted.

As part of a study published in the European Journal of Clinical Nutrition, researchers gave participants 240-calorie servings of 38 common foods and then tracked how satiated individuals felt and how much food they ate later in the day. The study authors ranked the foods, using white bread as a reference point. Eggs ranked 150 percent more filling than white bread.

Because eggs are so filling, they may assist with weight loss. A study in the Journal of the American College of Nutrition, overweight women consumed an equal amount of either a bagel or eggs for breakfast. The researchers tracked how much food participants ate for 36 hours after the meal and had participants fill out questionnaires regarding food cravings and feelings of satiety. Compared to those who ate the bagels, the egg-eating group felt more satiated after breakfast and ate fewer calories overall during the 36-hour window.

The protein in eggs helps build and maintain muscle, so they’re a great snack option post-workout. But protein performs many other important functions in the body as well. “You need it to put meat on your bones and to make hair, blood, connective tissue, antibodies, enzymes, and more,” Harvard Health Blog revealed.

Although people tend to assume all the protein in an egg is in the white, that’s not the case. In fact, according to the Encyclopedia of Food Chemistry, 50 percent of the protein is in the white, 40 percent is in the yolk, and the remaining 10 percent is in the shell and membrane lining the shell. (via ScienceDirect). Though we can’t recommend munching on the shell — even die-hard egg fanatics won’t go there.

When it comes to protein, eggs offer both quantity and quality. A single egg contains 6 to 8 grams of protein, according to the Cleveland Clinic, and includes all the essential amino acids in the proper proportion. And the proteins in eggs have the highest digestibility of any food, meaning our bodies can actually absorb and use a very high percentage of the protein in eggs, a study in The Journal of Nutrition confirmed.

Swapping out your morning pancakes or sugary cereal for a plate of eggs could help you better manage your blood sugar levels, whether you’re diabetic or not. In a 2018 study published in Food & Function, overweight and obese individuals with either prediabetes or type 2 diabetes were given either one egg or an equal amount of egg substitute daily for 12 weeks. At the end of the study, the egg group’s fasting glucose levels had dropped an average of 4.4 percent, and markers for insulin sensitivity had also improved.

If you’re eating only egg whites rather than whole eggs, you may not get these benefits. According to research published in the Annals of Nutrition and Metabolism, it was found that eating egg yolks or whole eggs reduced post-meal spikes in both glucose and insulin in nondiabetic participants. Nevertheless, many experts recommend diabetics to limit their egg consumption to three per week.

Move over carrots — eggs may be the key to safeguarding the health of your eyes. That’s because they contain lutein and zeaxanthin, antioxidants essential for good vision. As WebMD explained, these two compounds protect the eyes against damage from ultraviolet light. They may also help prevent macular degeneration and other age-related eye conditions. Individuals with higher levels of lutein and zeaxanthin in their eyes tend to have better vision, especially at night.

Like most of the other nutrients found in eggs, lutein and zeaxanthin are concentrated in the yolk. In an interview with News Medical, Dr. Jeffrey Blumberg, a professor at the Friedman School of Nutrition Science and Policy at Tufts University, noted, “One egg yolk provides approximately 200 micrograms of lutein, and lutein in eggs is 200-300 percent more bioavailable than vegetable sources of lutein.” This is because, unlike vegetables, eggs provide these antioxidants in a lipid (fat) form, which is easier for our bodies to process.

Although we often think of vitamin D as the “sunshine vitamin,” it’s also present in some foods, especially fatty fish. According to the National Institutes of Health, however, most Americans have trouble meeting the recommendation of 10 micrograms of vitamin D from food and beverages daily.

The yolks of regular eggs have a small amount of vitamin D — approximately 1.1 micrograms. But when chickens are fed a diet supplemented with vitamin D, the vitamin D levels in their eggs increase substantially. Hens that are able to roam outside in the sun also produce eggs with higher vitamin D levels. According to a 2014 Nutrition study, the eggs of pasture-raised chickens had three to four times the vitamin D levels of eggs from chickens kept indoors. If you’re looking for eggs from pasture-raised hens, you’ll need to read nutrition labels carefully; terms like “cage-free” and “free-range” might not mean what you think they do (via Certified Humane).

Eggs are a great source of choline, which plays an important role in brain health. According to Harvard Health Letter, choline assists with the creation and release of a protein called acetylcholine. Acetylcholine conducts signals between neurons and plays an important role in cognition and memory. In fact, individuals with Alzheimer’s disease have lower levels of acetylcholine in their brains, and medications to treat the early stages of the condition work by blocking the enzyme that breaks down acetylcholine.

The National Institutes of Health (NIH) recommends adult men get 550 milligrams of choline a day, while nonpregnant women need 425 milligrams. While beef liver is the best dietary source of choline, eggs are another (arguably more appealing) option. One egg provides approximately 147 milligrams of choline, which resides in the yolk. And there’s a good chance you need more choline; the NIH reported that most Americans don’t consume the recommended amount. Average daily intake was only 402 and 278 milligrams for men women, respectively.

In addition to safeguarding your mental faculties, the choline in eggs may also help protect against anxiety and depression. According to the Brain & Behavior Research Foundation, depression may be caused by low levels of acetylcholine, a neurotransmitter created from choline that carries signals between brain cells. This theory goes against the longstanding belief that depression is the result of low levels of a different brain chemical: serotonin.

Antidepressants focus on raising serotonin levels, but increasing acetylcholine levels may in fact be something that’s needed. As neuroscientist Marina R. Picciotto explained, “Serotonin may be treating the problem, but acetylcholine disruption may be a primary cause of depression. If we can treat the root cause, perhaps we can get a better response from the patient.”

Eating more choline-rich eggs could give your body the raw materials it needs to produce more acetylcholine. And, in turn, this could help treat or reduce the risk of both depression and anxiety. A study published in The American Journal of Clinical Nutrition found that individuals who consumed the least amount of choline had a 33 percent greater chance of having anxiety. The researchers did not, however, find a link between choline consumption and rates of depression.

Is your morning scramble increasing your cancer risk? According to a study published in the Asian Pacific Journal of Cancer Prevention, those who ate the most eggs had significantly increased risk for certain cancers when compared to those who ate the fewest eggs. Egg fanatics were 2.86 times more likely to get breast cancer, 2.23 times more likely to get bladder cancer, and 2.02 times more likely to get oral and throat cancers. They were also found to be at an increased risk for prostate, GI tract, colorectal, and lung cancers. Overall, the people who ate the most eggs were 1.71 times more likely to have some form of cancer than those who ate the fewest.

While those numbers may sound alarming, it’s important to remember that correlation doesn’t necessarily equal causation. The eggs themselves may have a direct impact on cancer risk, or it may be that those who eat the most eggs are simply more likely to have other risk factors for cancer.

You may think that an egg is an egg, but preparation method matters. Although consuming raw eggs as part of a protein shake is something we normally associate with hardcore bodybuilders, the protein in raw eggs isn’t as digestible as cooked egg protein.

One study found that while individuals could absorb 94 percent of the protein in cooked eggs, they could only digest 74 percent of the protein in raw eggs. That’s because heat helps break down proteins, essentially beginning the digestion process before the food even enters our mouths. Another issue with raw eggs is avidin, a protein found in egg whites. When uncooked, avidin binds to biotin, making it difficult for the body to absorb the important vitamin.

Nevertheless, heating does destroy certain nutrients. As studies have shown, cooking eggs reduces vitamin A content by 17 to 20 percent. Baking eggs in the oven for 40 minutes or longer reduces vitamin D to just 39 to 45 percent of its original level. Boiling eggs can reduce their lutein and zeaxanthin content by 22.5 percent, while microwaving causes a 16.7 percent reduction.

While the idea of gulping down a raw egg may sound disgusting to you, perhaps you enjoy authentic Caesar salad dressing or the occasional bite of cookie dough. Or perhaps you simply prefer your eggs with a runny yolk. If you eat raw eggs, or even undercooked eggs, you could be putting yourself at risk for serious foodborne illness. According to the Centers for Disease Control and Prevention (CDC), Salmonella infection from eggs can cause diarrhea, vomiting, fever, and abdominal pain. These symptoms usually last four to seven days. Individuals younger than five, older than 65, or immunocompromised are at greater risk for severe, even life-threatening illness.

Fortunately, Salmonella contamination is relatively rare, affecting approximately one in 10,000 to 20,000 eggs, Benjamin Chapman, an associate professor and food safety specialist at North Carolina State University told LiveScience. If a chicken’s ovaries are infected with Salmonella, the bacteria can enter the egg as it’s being formed. Salmonella-containing droppings can also contaminate the shell once the egg has been laid.

To avoid Salmonella, the CDC recommends cooking eggs until both the white and yolk are firm. If you’re making something that calls for raw or only lightly cooked eggs, using pasteurized eggs is a safer bet.

If you have an egg allergy or egg sensitivity, it’s important to avoid eggs in all forms. Individuals who are allergic to eggs have an adverse immune response to the proteins in the whites and/or the yolk, the American College of Allergy, Asthma & Immunology explained. Symptoms can include GI upset, hives, swelling in the mouth and tongue, shortness of breath, and wheezing. In some cases, severe reactions can lead to life-threatening anaphylaxis.

While 2 percent of children are thought to be allergic to eggs, 70 percent will outgrow the condition by their mid-teens. Even so, WebMD estimates that 2 million American adults are allergic to eggs. The website even noted that adult-onset food allergies are on the rise.

It’s also possible to be egg intolerant. As with other food sensitivities, egg intolerance doesn’t involve the immune system like a food allergy does, Healthline revealed. Symptoms are usually confined to the GI tract and include abdominal pain, bloating, cramps, diarrhea, nausea, and vomiting. While food allergy symptoms tend to occur immediately after eating the problematic food, symptoms of an egg intolerance may take hours or even days to appear.

If you’re getting bored with your run-of-the-mill chicken eggs, consider switching things up and trying duck eggs. Duck eggs may sound exotic, but they’re easier to find than you may think. Check farmers markets and gourmet grocery stores.

Although the price per egg may be higher, duck eggs are bigger than chicken eggs, so total cost per meal is likely to be similar. You can use them any place you’d use a regular chicken egg, but you may need to adjust proportions. Two duck eggs are equivalent to three chicken eggs.

Although duck eggs are nutritionally similar to chicken eggs, there are some differences. Compared to a chicken egg, a duck egg has 2 more grams of protein, 7.5 more grams of fat, and 74 additional calories, according to Healthline. It has less choline, but more folate, iron, selenium, and vitamin A. Duck eggs also have substantially more vitamin B12 (168 percent of the recommended daily requirement versus chicken eggs’ paltry 32 percent). And, even if you’re allergic or sensitive to chicken eggs, you’ll most likely be able to safely consume duck eggs because many of the proteins they contain are different.