Eggs are an extremely popular food choice throughout the world. The primary choice of egg consumed by people is that of the chicken, however other eggs such as duck eggs, quail eggs and for those with a little money to spend, even fish eggs (caviar) are consumed. That said, chicken eggs are the favoured eggs by a large margin.

Chickens are raised both as sources of meat and egg throughout countless cultures; they are the most widely utilised animal for foodstuff throughout the world. In more recent times mass production of eggs for human consumption has been embraced particularly in the west.

In terms of macronutrients (ie the nutrients required in large quantities by people, primarily carbohydrates, proteins and fats) eggs provide a fantastic source of both fats and proteins. In fact, due to the richness of eggs as a foodstuff eggs were forbidden during Lent in the middle ages. It is this fat and protein richness which has made them a highly popular food choice with athletes and body builders.

As anybody who has ever cracked an egg open will know, the egg is split in to two very distinct parts; the white and the yolk. Both of these have completely different nutritional profiles. In short, the yolk provides all of the fat of the egg and a small percentage of the protein, whereas the white is comprised nearly entirely of protein and water. There is very little (less than 1%) carbohydrates in eggs, their macronutrient profile is more or less completely comprised of protein and fat.

Egg White Nutrition

As previously mentioned, the egg white (or albumin to give it its proper name) provides most of the protein in an egg. Egg whites make up the majority of the edible part, about 66% to put a figure on it. By weight egg whites are actually only comprised of about 10% protein, the rest of the egg white is water (about 90%) and trace nutrients. There are 40 different proteins within the white of an egg, which between themselves provide all of the amino acids required by the human body. Thats right, every single amino acid that you require to survive can be found in eggs, particularly in the white.

Amino acids are often referred to as the building blocks of life, they are essential for life (as we know it…) to occur. Every biological entity on the planet contains amino acids. When space probes go looking for signs of life on other planets it is amino acids they look for as they are the starting point of life and a sure sign that life may have existed on the planet. The long and short of all of that is that the protein found in eggs is fantastically important so you should make sure to eat plenty.

The egg white is also extremely rich in a nutrient known as choline. Choline is essential to cell functioning, in particular on the cell membrane and in communication between cells. Sadly, most western diets in particular are deficient in choline, something which comes with a number of health problems beyond the scope of this page, but you can learn more about it here. Eggs and red meat are regarded as the best sources of choline so it is important that you eat your eggs regularly (personally, I ensure I consume at least three a day but I’m quite a fan of eggs as this website would probably suggest).

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Egg yolk nutrition

As previously mentioned, the yolk (or vitellus as it is less commonly, but more accurately known) contains all of the fat found in eggs, some of the protein, and part of the vitamin and mineral profile of the egg. Typically the yolk of the egg makes up about a third of the edible part of the egg and is responsible for most of the “energy” that you get from consuming eggs. The yolk is particularly nutrient dense in that it is high in fats which are high in energy.

Now would be a great time to dispel something of a myth and a grouch of mine: eating fat doesn’t make you fat. Fats are not responsible for weight gain and are actually extremely good for you (they are particularly good for your hair and skin, as well as being vital for life – you fill find most athletes consume lots of fats in their diet). The problem with fats is they are very high energy (like carbohydrates), another way of putting this is that gram for gram they are high in calories.

People gain weight not by consuming fat, but simply by consuming more calories than they use. The problem is that high energy foods such as fats (like those found in egg yolks) and carbohydrates are high energy, so if you consume lots of them you are highly likely to be taking in more calories than you are using up, so are more likely to gain weight. Sadly, this has led to the widespread belief that fats make you fat and therefore you should cut them out of your diet. This really isn’t true, fats, particularly those found in eggs, are great for you.

In addition to the fat content of the yolk, 18 of the amino acids required for humans are found in the yolk in various protein complexes. Egg yolks are also rich in a number of important vitamins which are essential for healthy cell functioning. These include vitamins A, D and E. They also contain calcium, iron, magnesium and other important trace minerals.

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