The benefits of egg-white vs whole egg

Eggs, in all their formats, whether just the whites or the whole egg, are nutritional powerhouses. They are easy to find, cook and carry being a perfect snack packed with protein and nutrients. Eggs and egg whites are easily digested and absorbed by the body which makes them ideal nutrition packed foods for both children and adults with a variety of health goals. Whilst egg whites are a fantastic source of lean protein, whole eggs are also a great source of heart-healthy omega-3 fatty acids and other nutrients .

Whole eggs have been shunned by the health food industry for many years since high cholesterol levels were found to be associated with heart diseases. Food with high levels of cholesterol thought to be the main cause of high levels of unhealthy cholesterol. Scientists have since found that high levels of saturated and trans fat are the biggest cause of high levels of unhealthy cholesterol rather than dietary cholesterol.

One egg contains 187mg of cholesterol that is all contained in the egg yolk. Cholesterol is required for testosterone synthesis, which in turn, we need for vitamin D synthesis from sunlight and the reaction with cholesterol based compound which is based in the skin. Cholesterol is an important building block for the body to maintain a variety of tissues and the nervous system. Cholesterol is also needed by the body to make testosterone which the body requires to build muscle.

Whilst both egg whites and whole eggs are high in protein, 4g and 7g respectively, 1 large egg white contains only 17 kcal whilst a whole egg contains about 54 kcal. Egg whites have a negligible amount of fat whilst the egg yolk contains about 4g of fat (depending on the size of the egg). However, most of the fats in eggs are not saturated – approximately 1.6g is saturated fat which affects your heart and cholesterol levels. If you are trying to build muscle, the fat in whole eggs is especially important as very little of it is saturated fat and your body requires the energy to build muscle.

Whole eggs are a complete whole food with all the essential amino acids that humans require – the building blocks of protein. They are also an excellent source of essential vitamins and minerals that our bodies require to function well. Whole eggs contain most of the fat soluble vitamins A, D, E and K and are also a great source of omega-3 fatty acids and vitamins B (such as B6, B12), riboflavin, folate, and choline which are hugely important in preventing heart disease. Vitamin A is important for vision – one egg contains almost 5% of your daily required intake.

Whole eggs are one of the only natural sources of vitamin D other than fish so especially important to vegetarians. Vitamin D is important not just for calcium absorption but also for bone health in general. Low levels of vitamin D have been implicated in increased rates of heart and cardiovascular disease, cancer and diabetes amongst other health issues.

The yolk is great source of the essential amino acids of L-arginine and leucine which are important for growth hormone production and release along with those required for optimal muscle recovery and building. 1 whole egg can provide your body with 25-35% of your daily choline requirement and 5% of your folate requirement. Both folate and choline are required for the methylation process which is an important part of cell signalling and important in processes such as building DNA, liver detoxification and brain signalling. Choline is also an important part of cell membranes giving them fluidity yet ensuring that they are impermeable.

Whole eggs are also high in carotenoids lutein and zeaxanthin which we require for good vision. The yolk is high in minerals such as zinc and phosphorus that we need for our immune systems and bone-building respectively. Whole eggs are high in other muscle recovery and building minerals such as zinc and iron.

Recently, the Barilla centre of food and nutrition has devised an updated food pyramid model based on the Mediterranean diet which looks at both health and nutrition as well as impact on the environment. In the double pyramid model, eggs are recommended as a source of protein, vitamins and minerals as they have less impact on the environment than meat, fish and cheese .

As you can see, whole eggs are a power food packed with protein, vitamins and minerals with most nutrients contained in the egg yolk. However, they do contain higher levels of fat so when making dishes using lots of eggs such as omelettes, frittatas and soufflés, substitute half the eggs with egg whites.

References
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[1] Front Nutr. 2015 May 4;2:9. doi: 10.3389/fnut.2015.00009. eCollection 2015.

Working toward Healthy and Sustainable Diets: The “Double Pyramid Model” Developed by the Barilla Center for Food and Nutrition to Raise Awareness about the Environmental and Nutritional Impact of Foods.

Ruini LF1, Ciati R1, Pratesi CA2, Marino M3, Principato L4, Vannuzzi E2.