Cool Facts About Eggs

You could fight crime with these things, and I'm not talking about whipping them at some bad guy's head.

Various foodstuffs, unbeknownst to most of us, have serious superpowers. Take for instance the following bit of science about something that sits in nearly everyone’s fridge garnering little fanfare:

“You may fascinate a woman by giving her a piece of cheese.”

It’s true. I read it in a book.

And then there’s my personal favorite, eggs. Like cheese, they have some serious mojo (although not in the woman-fascinating sense). Following is some strong evidence to support that claim, along with some useful or semi-useful trivia about these chicken-butt wonders:

1. Eggs are a Great Fat Loss Tool

High-protein foods in general are known to have a high satiety index (SI), but eggs also have the unusual property of suppressing plasma ghrelin levels (ghrelin is a hormone associate with appetite stimulation): the less ghrelin swimming through the blood, the less you want to binge on Reese's Pieces.

Eggs are also thought to reduce lipid absorption, in addition to also inhibiting lipase activity, both of which would logically contribute to a reduction in abdominal fat.

One study of 25 men compared the SI effects of eating iso-caloric breakfasts consisting of either eggs or bagels (Missimer et al, 2017). Okay, that's not much of a contest – the eggs were more filling than the bagels, but what was surprising is that guys who had the egg breakfast consumed fewer calories over the next 24 hours, meaning that the effect of eggs on appetite suppression is no rapidly fleeting thing.

Another study that compared eating eggs to bagels (what's with all the bagel studies?) for breakfast found that the egg group had a 65% greater reduction in waist circumference and a 10% greater reduction in body fat. Again, not much of a surprise, but no differences were found in the cholesterol levels of the two groups, despite the egg group ingesting an extra 400 mg. of the stuff every day (Rueda, et al, 2013).

2. Eggs Appear NOT to Raise Cholesterol Levels

The average large egg contains 187 mg. of cholesterol, which is a lot, especially when medical science recommends you limit your daily consumption to 300 mg. or less.

Given that eggs contain so much cholesterol, it's always been assumed that they impart a bunch of that cholesterol to your blood, but the findings have been inconsistent. While some studies have shown them to elevate blood levels, a lot of them have shown that egg consumption doesn't affect cholesterol at all.

Eat one egg a day, zip. Eat two eggs a day, also zip. Even eating four eggs a day, in some studies, has shown that eggs are largely benign when it comes to clogging your pipes.

The authors of a recent study (Kim, et al. 2018) think they may know why. They believe that the cholesterol in eggs isn't well-absorbed by the human body. According to them, a couple of phospholipids found in egg yolk (phosphatidylcholine and sphingomyelin) influence intestinal lipid metabolism and decrease the lymphatic absorption of cholesterol. Then there's the egg white itself. It too appears to limit cholesterol absorption by inhibiting the micellar solubility of cholesterol in the intestine.

If these theories prove to be correct, it looks like nature has equipped eggs with a built-in failsafe method to protect the humans who eat them.

3. Egg Protein is Best for Skeletal Muscle Health

The protein digestibility-corrected amino acid score, or PDCAAS, is the gold standard when it comes to measuring protein quality. The score is a combination of a particular protein's digestibility and how well it fulfills amino acid requirements.

So anything over 90% is considered pretty damn good. Soy protein, for instance, has a PDCAAS of 90 to 93%, while meat and fish come in at a hefty 92-94%.

Eggs, however, clock in at a surreal 118%. How do you get a PDCAAS over a hundred? Well, not only is egg protein digested at a 97% rate, it also contains an amino acid complement that, in many cases, exceeds human requirements. Hence the mathematically puzzling number.

Still, most of the people who work with PDCAAS don't accept any number over 100%, so they just round down. Let's just say eggs have a perfect protein score.

 Multiple studies also show their anabolic strength. When Matsuoka, et al., fed male rats a diet consisting of 20% egg white protein or casein, the egg-protein rats were found to have a greater average carcass mass and greater gastrocnemius weight than the rats that were fed conventional casein. They attributed this difference between egg white and casein to greater net protein utilization (95% compared to 70% for casein) from egg white, in addition to the higher digestibility of the eggs.

Of course, eating whole eggs has been found to be even more anabolic than eating egg whites. Van Vliet, et al. (2017) fed young weight-trained men whole eggs or egg whites (18 grams of protein) and found that the whole eggs spurred a greater surge in mTOR, which is probably the most important cell-signaling complex for muscle growth. The higher the levels of mTOR, the greater the synthesis of protein.

Most importantly, that same Van Vliet study found that eating whole eggs increased post-exercise muscle protein synthesis about 45% more than plain egg whites.

This apparent superiority of whole eggs in promoting protein synthesis probably has to do with the assorted micronutrients, phospholipids, and microRNAs contained in the yolk.

The scientific literature is filled with similar studies, too.

4.Eggs Make Old People Young Again (Sort of)

You know that big thing at the bottom of the pool in “Cocoon” that allowed Wilfred Brimley and his pals to regain youthful hard-ons? Just a big egg. Okay, maybe not, but hear me out: Sarcopenia is the age-related decline of skeletal muscle mass and strength. The resultant loss of function can increase the risk of type 2 diabetes, cardiovascular disease, Alzheimer's and other forms of dementia, and even some cancers.

Then there's the peculiar malady known as "sarcopenic obesity," characterized by a big-time loss of muscle mass and concurrent rise in fat mass. This is why many old people look like Mr. Potato Heads pushing a walker.

While just eating virtually any kind of protein would help the elderly population, eggs seem particularly suited to the job.

The thing is, it's difficult for a lot of older people to get the requisite protein they usually need by eating big, unappetizing, intimidating hunks of meat.

They might also have difficulties chewing or swallowing and have pre-existing malnutrition or chronic diseases. Cutting into a T-bone or tackling a quarter-pound burger might seem daunting. Not only that, but they often don't feel like eating because of poor appetite or low caloric needs in general.

Eggs, however, as discussed, are incredibly easy to digest and can be eaten at any time, in addition to being inexpensive. It seems the only hurdle would be to convince old folks – who lived in the dark times when eggs were anathema to heart health -- that eggs appear to no longer be the cholesterol menace they were thought to be.

5. Eggs Protect Against Chronic Disease

Simply by enhancing skeletal muscle health, eggs can improve insulin sensitivity, reduce risk of prehypertension and hypertension, ward off cardiovascular disease and osteoporosis, and, in general, reduce overall risk of all-cause mortality.

On a molecular basis, chicken eggs are teeming with immunoglobulin Y (IgY), which is the avian equivalent of the mammalian immunoglobulin G. It's thought to protect the developing chicken embryo in the same way IgG protects human fetuses. Okay, so how's that going to help my Uncle Wilbur with the grippe? Well, IgY has been used to promote passive immunity to treat and prevent human and animal diseases caused by hostile microbes.

Egg proteins also contain the enzymes lysosome, avidin, phosvitin, and ovotransferrin, each of which put the whup on various bacterial life processes.

They even offer protection against inflammatory bowel disease and seem to suppress tumors of the colon (egg yolk proteins, specifically).

6. You Can Work Around Egg Allergies

Egg allergies are pretty common in children, but they also affect some adults. For some reason, the body's immune system becomes sensitized to the proteins in eggs and it overreacts, causing symptoms like skin rashes, hives, nasal congestion, and digestive upset.

These reactions are caused by one or more of five major potentially allergenic proteins in eggs. If any one or more of these proteins are ingested, the proteins trigger an immune response.

However, research suggests there might be a workaround. Proteins are of course composed of individual amino acids that form one or more long chains. However, when we heat them, the proteins break down into their individual amino acids.

See what I'm getting at? If you "destroy" the proteins through sufficient heat, you incapacitate the egg's ability to elicit an allergic reaction. Soft boiled or maybe even scrambled eggs still retain a problematic number of intact amino acids, whereas extensively heated eggs (hard boiled or fried eggs over "hard") might not.

There are, however, people who are super-allergic to eggs and even extensively heated eggs might not be tolerable. For those people, proceed cautiously and consider seeing an allergy specialist.

7. Why Eating Raw Eggs is Stupid

Remember that scene from the first "Rocky" movie where Balboa quaffs a glass full of raw eggs for breakfast? Well, if he had really done that every morning, he'd have showed up to his fight with Apollo looking quite a bit different than what was shown in the film.

He'd have had noticeable patchy, red, eroded lesions on his face and, also, if his trunks had slipped down, his groin. His eyebrows and eyelashes might have been missing, too, and he wouldn't have lasted one round because he would have been suffering from depression, lethargy, limb numbness, and even hallucinations.

The preceding are all signs of a biotin deficiency and it's what can happen if someone has a predilection for eating raw eggs. The problem is that raw egg (specifically, the egg white) contains a chemical named avidin, which binds to biotin, leading to deficiency. However, since avidin is a protein, it denatures when you cook the egg, thus preventing its ability to bind up biotin.

So don't be like Rocky. Cook your eggs.

8. And Don't Eat Just the Whites, Either

Some people, probably in an effort to avoid the cholesterol, or maybe just to avoid extra calories, eschew the yolks and just slurp up the whites. Big mistake. Especially for strength or physique athletes.

Scientists have found that eating whole eggs leads to increased production of testosterone, probably because they supply the testes with arachidonic acid, an intermediate in testicular steroidogenesis. As mentioned earlier, whole eggs have also been found to induce a surge in mTOR, which is probably the most important cell-signaling complex for muscle growth. The higher the levels of mTOR, the greater the synthesis of protein.

9. How Do I Know that Sucker is Fresh?

The shell of an egg is porous, so air passes through the shell, so much so that eggs develop internal air pockets as they age. That property allows you to test whether a questionable egg is fresh or old. Just plop it in a glass of water. If it floats, it's an egg drawing social security benefits. If it sinks, it's youthful and idealistic. Cook it quick and kill all its dreams.

10. I Forgot Whether the Eggs in the Fridge are Hard Boiled or Raw

To tell if a whole egg's been hard-cooked, spin it on its side. If it struggles to gain momentum and slows quickly, it's raw. But if it continues to spin quickly, it’s hard boiled. The reasons this happens is that a raw egg is liquid, its stability is compromised. The liquid sloshes around inside and prevents a smooth spin.

A hard-boiled egg, however, is solid inside so it can continue to spin at a rapid rate.

11. What's That Stringy White Stuff? Yucko!

A lot of people look at that stringy, gunky stuff that you often see clinging to the eggy yolk and automatically assume it's a chicken embryo. It's not. Stores only sell unfertilized eggs from respectable virgin chickens that are saving themselves for their chicken soul mate.

Those gunky strings are in fact what's called chalaze and they're just twisted membranes that, when intact, attach the yolk to the inside of the shell. They're completely edible and their presence tells you the egg is fresh.

12. Why the Hell Do Americans Refrigerate Their Eggs?

Eggs pass through the same dark cloacal tunnel as a chicken's feces, making them vulnerable to Salmonella and other bacteria. Eggs-perts from other countries will tell you that Salmonella poisoning is extremely rare, so they don't bother to refrigerate their eggs. Instead, they sit on shelves the same as their Cocoa Krispies, or as they're known in several of these non egg-refrigerating countries, Choco Krispis.

Eggs have a protective coating on the outside, known as the "bloom," which under ordinary circumstances, might protect the egg against microbial incursion. However, in a kind of irony, American egg distributors inadvertently wash the bloom off the egg to make sure it doesn't carry any Salmonella.

It's likely they'd be better off leaving the egg's natural bacterial barrier in place and let the egg protect itself. In any event, because the bloom has been washed off, Americans are advised to refrigerate their eggs to minimize bacterial infection.

13. Now You Know How Jeffrey Dahmer Made His Famous Medulla Oblongata Macaroons

If you're baking but find you’re out of eggs, you can use pig blood, or probably even human blood, as a substitute. Sixty-five grams of blood will replace one large egg. It seems egg and blood have similar protein compositions, particularly with the albumin that's largely responsible for both of their clotting properties.

All of this comes to us courtesy of the Nordic Food Lab, who are actually considering the possibility of using pig blood in baked goods and even ice cream. (Remember, these are the people who sacrifice people by stuffing them into a disemboweled bear's body and then placing it on fire…at least that's what I saw in that "Midsommar" movie.)

So, after reading all this, how do you like dem eggs now?

References:

Vliet, Stephan Van, "Consumption of whole eggs promotes greater stimulation of postexercise muscle protein synthesis than consumption of isonitrogenous amounts of egg whites in young men." Am J Clin Nutr, October 4th, 2017.

Bagheri, Reza, et al. "Whole Egg Vs. Egg White Ingestion During 12 Weeks of Resistance Training in Trained Young Males," Journal of Strength and Conditioning Research, Dec. 9, 2020.

Vliet, Stephan Van, "Consumption of whole eggs promotes greater stimulation of postexercise muscle protein synthesis than consumption of isonitrogenous amounts of egg whites in young men." Am J Clin Nutr, October 4th, 2017.

Michael J. Puglisi and Maria Luz Fernandez, "The Health Benefits of Egg Protein," Nutrients, 2022, 14, 2904.

Luoma, TC, "Luoma's Big Damn Book of Knowledge," Vintage Classics – Penguin Books, London, 17th edition, 2021.