Yolks vs. Whites
Cracking the Egg Conundrum
Eggs are one of the most nutritious foods on the planet. Think about it. By definition, an egg contains all the nutrients necessary to grow an entire chicken from a single cell. Why, then, do breakfast menus universally offer omelets made with only the egg whites? Quite simply, because eliminating the yolk cuts down on calories, fat and cholesterol. But, in addition to cutting calories, tossing that egg yolk also eliminates all the nutrients an egg has to offer.
What’s in Egg Whites?
Egg whites are the clear, thick liquid that surrounds the buttery yellow yolk at the center of an egg. Egg whites are made up of 90% water and 10% protein, and virtually no fat or carbohydrate. But, also virtually nothing else. Egg whites are also very low calorie. The egg white from one large egg is 18 calories and contains 4 grams of protein, while one whole cup of egg whites is 126 calories and contains 26 grams of protein. The protein in egg whites is also a complete protein, meaning it provides all nine essential amino acids in perfect ratio, which does make it a great vegetarian protein option, or a good choice for those on a calorie-restricted diet or for those trying to lose weight.
What’s in Egg Yolks?
The yolk of an egg is the nutritional equivalent of liquid gold. It contains all of the valuable nutrients provided by the egg. That is, 13 essential vitamins and minerals, including Vitamins A, D, K and B12, riboflavin, choline, folate, calcium, zinc, phosphorous, selenium and the carotenoids lutein and zeaxanthin. Choline is often referred to by nutritionists as the most important nutrient you’ve never heard of. It is essential to the brain and nervous system’s ability to regulate mood, memory and muscle control, and is used to build the membranes around all of our cells. A single egg yolk contains more than 100 mg of choline. Lutein and zeaxanthin are essential for eye health. The yolk also contains healthy fat and cholesterol necessary for hormone production.
Try Eating at Least One Whole Egg
At just 70 calories with four grams of fat and six grams of protein, a whole egg is not a high caloric price to pay for all the nutrients and macronutrients it provides. “I’m all about the whole food,” says nutritionist Jenn Gargiulo, RDN, CSSD. “Eat the yolk to get your choline!” However, if you are looking to boost your protein or volume of food and reduce calories, Gargiulo suggests eating one whole egg to get your vitamins and minerals, and adding liquid egg whites to increase bulk. Also, because dietary fats slow the absorption of protein, eating whole eggs – or adding at least one whole egg to your egg whites – will help you feel fuller for longer.
What About Cholesterol?
It is true that all the cholesterol found in an egg is in the yolk, but the fear of eating them is largely based on old data that has been debunked. In the year 2000, the American Heart Association revised its dietary guidelines and said adults could enjoy one egg per day. Then, in 2019, they stated, “Dietary cholesterol is not a nutrient of concern and eggs can be a beneficial part of a healthy diet.” Current research shows that up to three whole eggs per day is safe for healthy people, because consuming egg yolks does not adversely affect the level of cholesterol in your blood. Your liver produces cholesterol every day for the production of cells and hormones, and when you consume cholesterol in your diet, your liver simply adjusts the amount it produces to keep things balanced. The consumption of trans-fats and saturated fats is much more responsible for an increase in blood cholesterol levels; beware that bacon accompanying your eggs rather than the eggs themselves!
Not All Eggs are Created Equal
The nutrient content of eggs varies greatly based upon the type of food the hens who laid them were fed. Hens fed a diet fortified with vitamin D or high in omega-3 fatty acids will produce eggs that are much higher in vitamin D and omega-3s, which are essential for all of our body processes. But, there is no nutritional difference between white and brown eggs; the color is only an indication of the breed of hen that produced the egg.
How to Eat Your Eggs
From basic boiled to Benedict, there are so many ways to cook eggs. The healthiest would be soft or hard boiled, prepared with no butter, olive oil or other added fat to keep the egg from sticking to the pan. But, adding a small amount of olive oil or grass-fed butter to a pan to fry an egg, or to make a scramble or omelet with vegetables, is also a healthy and delicious way to enjoy eggs. You can also get creative with egg muffins or vegetable frittatas that can be taken as on-the-go breakfast options, or poached eggs over leftover vegetables for a quick dinner.